AudioCircle
Industry Circles => GR Research => Topic started by: jonsk2514 on 11 Feb 2021, 01:10 pm
-
Well, I am back at it. This time it is a combined build of a X-CS center channel and a X-LS pair. There is a lot to be said about the X-MTMs that I just finished. The X-CS should be a good compliment to them. The build of the X-LS is a result of having my youngest daughter over for a listen of the X-MTMs. She remarked that she has been thinking of building a set of speakers herself. She has the talent to do it. But, there is the time and money, both of which I have a bit of. Her, not so much. She only works about 9000 hrs a week (Ok, I exaggerate a little, just a little). Plus her birthday will be coming up. These should be a great present for her.
For these builds I will be drawing heavily from my experience from my build of the X-MTMs (https://www.audiocircle.com/index.php?topic=170542.0).
And I found someone (Thanks Mike) who did the exact same build and posted a link to it in the GR Research Build Threads sticky:
(https://www.audiocircle.com/index.php?topic=153612.msg1642306#msg1642306).
What a great resource! There are a ton of other resources showing the assembly of the X-LS speakers including Danny’s own set of videos:
https://youtube.com/c/GRResearch
Just look for his X-LS Encore play list.
And Peter Rawlings did a great assembly video of the X-LS speakers
https://youtu.be/5n3ZYGnEjgE
Peter has other videos showing finishes he as done.
I plan to use a mix of ideas for putting these together, which I hope will make the build go more quickly for me than the build of X-MTMs.
I have already laid out the cut plans for the 3 cabinets and found that they easily fit on one sheet of MDF.
Let the fun begin!
Starting with the cut plans:
(https://www.audiocircle.com/image.php?id=220771)
-
And so it goes. The long slide down the slippery slope of speaker building. Insidious in some ways, but on the bright side, there's always something on the horizon to pursue so it's rarely boring.
Good on ya for inducting your daughter...err, maybe not...
-
I am very familiar with slippery slopes and rabbit holes. :o
A while back ago I got into taking one of my cars to race tracks for “Track Days”. The friends who got me into doing that called it “Track Crack” :lol: Just think about the car upgrades one can do. And that was, like, 2 months after buying the car for this and telling my wife that “I am going to do nothing to the car”... :roll: When I can’t do that (winter time) I do down hill skiing. Again, there is always a new and improved set of skis to try. So what’s one more addiction. :rotflmao:
The best part about this “hobby” is that I can do it at most any time. It is not a function of weather or schedules. And once the builds are done, I can just sit a listen to them. Talk about the best of all worlds :thumb:
And today that slope just got steeper when I realized that I had another room that could use a set of speakers... Oh Ya... :lol:
-
I am very familiar with slippery slopes and rabbit holes. :o
A while back ago I got into taking one of my cars to race tracks for “Track Days”. The friends who got me into doing that called it “Track Crack” :lol: Just think about the car upgrades one can do. And that was, like, 2 months after buying the car for this and telling my wife that “I am going to do nothing to the car”... :roll: When I can’t do that (winter time) I do down hill skiing. Again, there is always a new and improved set of skis to try. So what’s one more addiction. :rotflmao:
The best part about this “hobby” is that I can do it at most any time. It is not a function of weather or schedules. And once the builds are done, I can just sit a listen to them. Talk about the best of all worlds :thumb:
And today that slope just got steeper when I realized that I had another room that could use a set of speakers... Oh Ya... :lol:
Lucky you, an extra room! I just finished a pair of speakers for a customer and liked them enough to try and figure out how I can get another room so I can have a pair myself.
To preempt any questions, no I do not like them better than my NX-Otica MTM/servo H combo. They are not in the same league. What they are is a great sounding fun pair of speakers to listen to. Norman posted about them over in the Enclosures circle.
I know, I can build an addition on the house .... :lol:
Mike
-
Good on ya for introducing your daughter... err maybe not...
:lol: But,
No, no problem there. She and I spent several hours jumping through YouTube posts and listening to great stuff... Jazz, classical, rock, blues. She is musically inclined and really appreciate the X-MTMs (actually blown away by how great they sounded). She is also really hard working. So, I am happy to do this for her.
I know, I can build an addition on the house .... :lol:
I love it!
To be honest, I have 2 rooms that need speakers, beyond the room I am already working on. A while ago I concluded that there was one room that needed a speaker upgrade and I think the X-Oticas would do well in there. I haven’t decided what would go well in the other room. I am just planning ahead... :lol: And then there will have to be a full sound system upgrade to go along with the X-Oticas... When will it end????? :duh: Never... :roll:
On the build front, I have finished making the long cuts of the MDF. I have proceeded with the same method I used for the X-MTMs (https://www.audiocircle.com/index.php?topic=170542.msg1806558#msg1806558). I really like the cordless router. This paired with the 1/8” down spiral bit works great for making these cuts. These cuts could be done on a table saw or with a track saw, but for my shop capabilities, the router works the best. And, Yes, I remembered my dust mask...
I will note that I always measure down from the far end of the MDF to size the next cut location. This way I always have a constant edge to measure from. If I measure up from the previous cut edge, any error (even a 1/32” from one side to the other) in the angle of the last cut will translate to the next cut. This can be compounded over several cuts. This way I ensure things don’t get skewed too much. Also, these cuts are a bit “rough” and there is room to make small corrections on the table saw, if needed.
Router with the 1/8” router bit and showing the extended router base on the router. I made this base from some 1/4” thick plexiglass for doing these kinds of cuts.
(https://www.audiocircle.com/image.php?id=220791)
A piece cut showing the cutting setup. The MDF has been raised so a vacuum hose can be placed under it to suck up dust. Works well for this.
(https://www.audiocircle.com/image.php?id=220792)
-
Progress is coming much more quickly than it did with the X-MTM. Surely using them for “practice” helped... :roll:
I have all of the MDF cut into panels for both the X-LS and X-CS speakers, and the braces for the X-CS. The pieces have been sized to be assembled with rabbits on all of the outside pieces, except the back, which will fit into the rabbits in the top, bottom and side panels. My arrangement of the rabbits is in a different order than what Peter shows in his video of the assembly of his flat pack (https://youtu.be/5n3ZYGnEjgE), but the idea is the same.
For my assembly, the front will have a rabbit on all 4 edges, the top and bottom will have rabbits on 3 edges, the side panels will have a rabbit on the back edge and none on the back panel. Each rabbit will be 3/8” deep and ~3/4” wide. All of the outside panels except the back are cut slightly oversized, so that will mean that the width of rabbit will need to be slightly greater than 3/4” to adjust for that.
Using rabbits also means that the length and/or width of each panel (except the front) will need to include the depth of the rabbit that it will be fitting into. The dimensions shown in sketch in the first post include the rabbit depth.
Once I made the long cuts in the sheet of MDF, the remaining cuts to lengths were, for the most part, done on my miter saw. Fortunately it has a pretty large throat and can accommodate the 12-3/4” board...
(https://www.audiocircle.com/image.php?id=220893)
But that is as large as the saw will take.
The remaining 15-1/8” board was cut on the table saw. I am not a fan of making a 15+ inch long cut on a table saw as I find it is way too easy to have a result that has edges that are at something other than 90deg to each other. Maybe that is just me, my saw or both, but is has happened to me in the past.
This time was a success! :dance: Moving on, and not looking back at that one... :D
I did remember to double and triple check measurements and layout on each piece to be cut. More than once I found I had measured an inch less than what I wanted or that my square wasn’t square on the piece when I drew the cut line. Putting a full cut line on the piece was especially helpful when cutting on the miter saw as I could check the saw’s travel along the line and see if it was making a right angle cut. Doing this showed that I needed to re-align the saw (who bumped that out of wack? I don’t know... :duh:).
The resulting cut pieces for a pair of X-LS speakers and a X-CS center channel:
(https://www.audiocircle.com/image.php?id=220894)
I still need to cut the 45deg braces for the X-LS cabinets and see about getting a piece of dowel rod for the cross brace as Peter shows in his video. I like that better than the suggested 3/4” x 3/4” square piece shown on Danny’s sketches.
-
Hey everyone...
2 questions about braces for these things...
- The X-LS uses only corner braces and a small side to side brace. Danny’s plans show 4 corner braces; 2 side to top and 2 side to back. However, in Peter R’s assembly video of his flat pack he shows a third pair going in; 2 front to side, in between the woofer and tweeter. Did I miss something in Danny’s sketches, or is Peter just making his flat pack cabinet more rigid?
- The X-CS has 4 braces. 2 of them (Brace “B”) are 10” long with a 5.5” dia semicircle cutout, and with one long leg and one short leg. Is that short leg necessary or can they both be of the same long length? From mlundy’s build (https://www.audiocircle.com/index.php?topic=117653.msg1247635#msg1247635) it looks like the crossover will fit without making that one leg shorter. So, part “b” to that question... if both of the legs can be of the same length would there be anything wrong with making that a 5.5” hole a full circle and have a semicircle of some diameter to finish it off? My thought is to make the box even more rigid... Not that it isn’t rigid enough now, which may be the case.
So, any thoughts?
-
More progress...
I have finish the rabbits on all of the panels for both speaker designs. This was really quick compared to the X-MTMs, which are a much larger speaker. I did these the same way as I did for the X-MTMs (https://www.audiocircle.com/index.php?topic=170542.msg1814590#msg1814590). That is, I roughed in the rabbit on the router table in 2 passes. The first being a little less than 3/8” deep from the edge and the second being a little less than 3/4” deep from the edge. The final sizing of the rabbits was done on the table saw with the fence set to 3/4”. While this sequence of cutting takes a little more time, I fell it gives me a bit “cleaner” rabbited edge on the pieces. This being a sample showing the top panel for the X-CS:
(https://www.audiocircle.com/image.php?id=221062)
One of the things I did was to layout on each panel where each rabbit was to be made.
(https://www.audiocircle.com/image.php?id=221059)
This way, I can make and correct mistakes in pencil first... Yes, I did make a few, like, too many rabbits on the side panels which only required one... :duh: And it was a good thing that it was in pencil because if I had done that with the router, it would be off to cut a new panel... :cry: Even at that, I did route one on an un-marked end. Fortunately, the end that was cut could have been used anyway, but just a bit frustrating that I didn’t pay attention to the markings I made and it could have been more serious mistake. :nono:
Dry Fitup Time! :bounce:
(https://www.audiocircle.com/image.php?id=221060)
Pretty much of a success.
The panels for the X-CS all fit perfectly. The width of braces (top to bottom wise) is a bit smaller (~1/6”) than the height of the interior but that will be filled by the Titebond “thick and chewy” glue :lol: Ok, that is Titebond Quick and Thick. I plan these to be just butt joints as others have done, so that glue should work well for that.
Now the question is, how did I get the panels for the X-CS all sized about perfect and I missed on the X-LS? I don’t know, but a few of the X-LS panels are a touch oversized which is affecting the overall fitup and there are some gaps as a result. This will take some minor trimming to correct, which is OK. I guess, just expect this to be the case and plan on a few corrections. This happened on the X-MTMs, too. The X-LS panels will be easier to rework than those just because of their smaller size.
-
As I noted, the panels for the X-LS cabinets were a little more oversized than those for the X-CS, so there was some trimming that needed to be done. The table saw came in handy for that.
(https://www.audiocircle.com/image.php?id=221151)
The gap in the back panel to the top was more that I anticipated. This was also reflected in the gap between the front panel rabbit and the top panel. Both side panels needed to be trimmed to adjust their height by less than 1/16”
Similarly the fitup to the rabbit on the top and bottom panels was off slightly.
(https://www.audiocircle.com/image.php?id=221152)
The width of the back panel and the rabbit on the front panel needed to be adjusted slightly to correct this. With this done, the dry fitup was deemed a success.
Moving on to cutting holes in the X-CS braces
The longer of the 2 set of braces have “C” shaped cutouts at each end. These are best cut by placing the blanks end to end and cutting the “C’s” as a single hole. I held the panels together with pipe clamps and had a thin board between the braces and the clamps to keep from nicking the metal clamp with the router bit.
(https://www.audiocircle.com/image.php?id=221153)
Swapping ends, I did the same cut in the other ends.
(https://www.audiocircle.com/image.php?id=221154)
(https://www.audiocircle.com/image.php?id=221155)
I went off script here with the smaller set of braces for the X-CS. These are the same size as the respective braces in the X-MTMs I just finished, but in the X-CS design these are cut out more than in the MTM design.
It seems that the cutouts are for the crossover, but in other posts the crossover seems to fit within the spacing of these braces. So, I went with the more rigid brace design the X-MTM uses. I know this takes up a little more volume inside the cabinet, which will slightly affect the low end response. However, given this is to be a center channel, where low end is less important, I expect this will be acceptable. I will wait to glue these in to make sure the crossover fits. These can be easily modified back to the X-CS design if needed.
Braces fitted into the X-CS cabinet.
(https://www.audiocircle.com/image.php?id=221156)
The modified (or X-MTM style) brace can be seen in the right side of the picture. The front panel also has the layout for the drivers on it...
Getting to be time to order components. Now if the weather in Texas would get better... :shake:
-
Off to a great start! :thumb:
-
This one's going so much faster!
-
Off to a great start! :thumb:
This one's going so much faster!
Great start and going so much faster... Great combination... :thumb:
It helps that I had all of that “practice” with the X-MTMs, plus these are easier. :roll:
I have been following the Texas weather issues and reading Danny’s posts about how it is affecting him and getting kits out. I may have a bit of a delay while I wait for the kit parts to get delivered. I’ll talk to Danny tomorrow about placing an order. I want to wait until I have drivers in hand to cut holes and the tweeter recesses. This way I can make some practice cuts with parts in hand so I know I have setting that will allow everything to fit.
-
Components for both speakers are on order. :dance:
With the remnants of weather issues in Texas still lingering, I expect that these will take a bit to get here.
In the meantime, I am working on the corner braces and the cross brace for the X-LS. I like Peter’s idea of using a dowel for the cross brace and locating it in a round pocket in each side.
(https://www.audiocircle.com/image.php?id=221264)
This is a screen shot taken from Peter’s X-LS assembly video - https://youtu.be/5n3ZYGnEjgE - This has been a go-to video for me.
-
When in doubt, Listen to Peter :wink:
-
Thanks for the vote of confidence, I did spend a little time figuring out how to make that work and not have the potential to bow the sides or interfere with assembly. Give some clearance in the pocket to dowel interface, and use PL Premium as the adhesive in this one place only. The dowel in my kit is a little shy of the pocket floor to pocket floor dimension, which the expanding characteristic of the PL takes up as it cures.
-
Looking great so far, and yes a bit quicker now that you have the first build under your belt. Very cool that you’ll be able to share the hobby with your daughter too!
-
When in doubt, Listen to Peter :wink:
:bowdown:
:thumb:
Thanks for the vote of confidence, I did spend a little time figuring out how to make that work and not have the potential to bow the sides or interfere with assembly. Give some clearance in the pocket to dowel interface, and use PL Premium as the adhesive in this one place only. The dowel in my kit is a little shy of the pocket floor to pocket floor dimension, which the expanding characteristic of the PL takes up as it cures.
I learned a lot from that one video. From simple things like the idea of brushing the glue out, to the edge rabbits and the dowel. A lot of these things seem obvious to anyone who has done this before, but in building the MTMs this was all brand new to me. So, thanks for taking the time to make that video.
Looking great so far, and yes a bit quicker now that you have the first build under your belt. Very cool that you’ll be able to share the hobby with your daughter too!
Thanks.
And I know she will appreciate them for what they are. :thumb:
-
Peter's videos were great learning material, especially for my NX-Studio assembly. I think he used something like 12 clamps per speaker? :o
I made do 8 clamps & 2 strap clamps. :P
But the info also really came in handy when gluing up the cabinet portion of the X-Statik. Being larger and more complicated, you gotta learn to work quickly and make adjustments asap.
Better to learn all the info sooner than later before you make a mistake that can't be corrected... :P
-
And practice. :thumb:
How hard can it be to use a template guide and router to make a small circular recess in a piece of MDF? :shake:
For some of us less talented people - 2 days... :dunno:
It is a good thing I am in the habit of practicing new things, even if they seem simple. I have a nice set of template guides that I got while working on the X-MTMs and never used. Here’s my chance to do something new...
(https://www.audiocircle.com/image.php?id=211467)
I even figured out the math for selecting the right guide...
(template hole dia) - (guide OD) + (bit dia) = recess ID....
So ... 1.25” - 0.625” = 0.625” + 0.25” = 0.875”
Perfect for the 13/16” dowel rod (otherwise known as an old broom handle) I had laying around. Just enough clearance for the PL adhesive, as Peter recommend.
(https://www.audiocircle.com/image.php?id=221327)
Day 1 and an hour+ of practices. You think I could get a recess that the dowel could fit into? No. :icon_twisted: Do you know many times I checked my math? How many times I measured the dia of the recess and the dowel rod? I even tried a different combination of template hole and guide diameters, with no success.... :banghead:
My wife is a very smart person... Much smarter than me. Sleep on it. It will look different in the morning. - She says....
Day 2 - Get the template out. Install the guide in the router base. New piece of scrap MDF. Take another shot at getting this right. Make my first pass and lift the router out of the way. The recess is filled with MDF dust. Not surprised as I saw this yesterday. Vacuum the dust out and take one more pass with the router. Take the router away and clean out the recess again. Try the dowel... It fits perfectly... :bounce:
What’s different? Different day? No, I never thought to take that second pass with the router when I was practicing the day before. :duh: It seems that the router dust was enough to interfere with the guide and template and it was enough to prevent me from getting the right diameter recess. I had a vacuum attached to the router and was using an up spiral cutter, which I thought would be enough to keep that from happening. But apparently not.
I actually went with a straight flute cutter as it made a smoother surface at the base of the recess.
(https://www.audiocircle.com/image.php?id=221328)
I took several shots at getting a smoother edge to the recess, but I think it is just the “cheap” MDF I am using.
(https://www.audiocircle.com/image.php?id=221329)
Not too worried about the edge as a little sanding will take care of that. Dry fitup and a perfect fit.
(https://www.audiocircle.com/image.php?id=221331)
One of the things I did was to layout the location of the template hole on the side where the recess will go.
(https://www.audiocircle.com/image.php?id=221330)
This provided me with a way to make sure the template is located correctly and that serves as a back check for doing the layout correctly. The template is a match to the sides that the recess will be in.
I should also note that per Danny’s sketches this cross brace is a little higher than center in the bottom to top direction. This makes the sides “handed” and they need to be installed correctly.
I finish the day with routing the corners of the braces for the X-CS cabinet and did a dry fit.
(https://www.audiocircle.com/image.php?id=221334)
There is not a lot of room to fit the crossover board into places between the outer and inner braces. I will see what I can do with the layout of the crossover to see if I can make this fit as-is. If not, I can return the outer braces to the design shown for the X-CS.
-
There is not a lot of room to fit the crossover board into places between the outer and inner braces. I will see what I can do with the layout of the crossover to see if I can make this fit as-is. If not, I can return the outer braces to the design shown for the X-CS.
Looks good!
As far as I know the crossover board does not have to be one board. Maybe when you put the high and low circuits on different boards they will fit better.
-
Thanks! :thumb:
And, yes, that is a consideration. I have seen that suggested for other speakers. In the design of the X-CS, Danny’s sketches show the outboard braces with no middle web and a shortened lower brace leg. I see now that might be a practical compromise between having stiffness in the cabinet and having access to the crossover.
I have ordered the components from Danny for both the X-CS and X-LS. My plan is to hold off going any further with these, other than make the corner braces. When I get the hardware from Danny, I will “test” assemble the crossovers (not solder them) and see how they will fit. Then I will decide on a path forward.
-
I got my “care” package from Danny yesterday. :dance:
Time to get back to work. I have waited as I wanted parts in hand before making hole cuts and recesses so I can practice and ensure everything fits properly before tackling the actual parts.
I did find out something interesting while I was waiting. I didn’t have the top baffle for the X-CS well support while it was just sitting around.
It warped! :slap:
Not a lot; maybe 1/16 inch, but still. MDF has no structural rigidity at all. No wonder Danny designs in so much internal support. Judging by how much that one piece warped, one might think my X-MTMs would look like pretzels in just a few weeks without all that they have in the way of braces.
That aside, back to work now... :green:
-
I just finished my X-CS crossover over the weekend and mounted it to the bottom before gluing it on. This allowed me to mount the board and attach the no-rez in one solid piece.. The spacing between brackets for the crossover looks about the same as the MTM, so the same board size and layout works. In my case, I made the mistake of soldering before the final mounting on the board, so my resistor is off the board a little and I needed to carve out the foam a little :duh:. Lessons learned. I didn't make the same mistake on my MTM crossovers.
(https://www.audiocircle.com/image.php?id=222073)
-
Thanks for the warning ...
For my MTMs I did lay the crossover parts out on a board, without soldering and then made sure it would fit. With that trial fit I made sure it would fit through the opening for the woofer, just in case I had a need to remove it at a later date.
My plan is to do something similar with the X-CS, only I think I will leave the top baffle for last for gluing. Not sure on quite yet. One reason I have waited to proceed with gluing is I want the crossover parts to do a trial fit. In particular I cut the outboard braces the same as those in the MTMs, which is different from the plans for the X-CS, and I wanted to see if the crossover would fit in or if I need to modify those braces.
JW - I have seen others who have mounted the resisters on top of the caps. I know functionally what you have should be OK, but if for some reason you don’t want the overhang, you could do that... Just bend the wire to the resistor 180 deg and tie the resisters to the cap that is next to it. I see the board is already mounted, so this might be an academic thought.
-
Opps in the making... :duh:
Last night I went through the box of goodies, checking what I got, and sorting all the parts out in those for the X-CS and X-LS. While I was labeling everything it dawned on me that while I have 2 woofers for the X-LS speakers and 2 woofers for the X-CS speaker, and they look the same, they are actually different woofers... And I wondered if I mis-marked them as to which design they go with.
This could have been a mess if this came to light in my feeble brain after I finished the assembly. Or worse yet, if I mixed up the 4 and had miss-matched woofers in the X-CS and between the 2 X-LS and had them all finished... :bawl:
As it was, I looked for marking, admittedly, not too hard. Didn’t readily see any, so I pulled out the trusty ohm meter and checked them. Yup, mis-marked them. At least the wrapping for them is now correctly marked. Later, when the wrapping comes off I will mark the drivers themselves with a really bright silver Magic Marker...
-
At least you caught it. Would have been really weird when you finished them and they all played at different volumes!
-
“Weird” - that would be a word for it.
Then would come the:
:scratch:
:oops:
:banghead:
:lol:
-
A bit more progress. I have received all of the hardware for both speakers. The last bits were the ports for the X-LS. I know that people complain a lot about the USPS, or at least the complaints make the news, but wow, I think they have nothing on UPS:
(https://www.audiocircle.com/image.php?id=222879)
I wonder what this would have looked like if it was marked “FRAGILE”? :nono:
It looks like there are some molding channels that need to be remove...
(https://www.audiocircle.com/image.php?id=222882)
Not a big deal.
More practice. Fortunately, all of the driver holes are the same between these speakers and the X-MTMs. Also, I was “smart” to have saved all my notes from that build... : :roll:
I am using a hole cutting jig for this...
(https://www.audiocircle.com/image.php?id=211466)
To cut the holes. This works really well, with a little practice. For the base drivers the sketches call out a 5-3/4 inch hole. For the X-MTMs I found that a slightly smaller, 5-11/16 inch, hole worked well to give a bit of snug to the driver.
I am using a 1/8 inch up spiral cutter, which mean the center pin location for the jig needs to be increased by 1/8 inch to compensate for the fact the jig’s scale is based on a 1/4” cutter.
So, practice with the pin set for a 5-13/16 inch hole
(https://www.audiocircle.com/image.php?id=222883)
Perfect. Same as I got for the X-MTMs, go figure ... :lol:
As you can see I did the hole cutting on a board, using a couple of clamps to hold the piece being cut. The clamps bow a little when tightened, which holds the piece in place.
Once I cut the holes in the front baffle for the X-CS I did a dry fit of the pieces making up the cabinet, except for the top. Because I made the outboard braces like the ones in the X-MTMs instead of what is shown in the X-CS sketch, I wanted to make sure I could fit in the crossover through the hole for the driver. I used a piece of 2x4 to mockup the approximate size of the crossover that would being going in there and slid it in through the opening and around the braces...
(https://www.audiocircle.com/image.php?id=222884)
(https://www.audiocircle.com/image.php?id=222885)
(https://www.audiocircle.com/image.php?id=222886)
So, it fits, with room to spare. From here I will lay out the crossover parts on a piece of cardboard and make sure that fits before going any further on this speaker.
-
Looks good!
As far as I know the crossover board does not have to be one board. Maybe when you put the high and low circuits on different boards they will fit better.
True, you can split the crossover up if needed Jon. Check out the boards Hobbs made for his X-statiks.
-
True... :thumb:
I need to do the crossover layout and doing it on cardboard will make easy to try it as one piece. If it doesn’t fit, splitting it will be an easy solution.
-
Best laid plans of mice and men...
Or, is it - measure 4 times and cut twice.
Ok, a fixable screw up... :P
It seems that even practicing, measuring twice, and doing a layout of what is to be cut doesn’t not prevent errors.
Practice I did. In particular I did a practice run of the tweeter cutout with the recess. The cutting order is important here with the recess needing to be cut first, then the through hole is cut. The recess needs to be “right on” as once the hole is cut, it will be difficult to fix it afterwards.
I always do a pencil layout, in particular to ensure I have selected the correct pin hole in the router jig.
(https://www.audiocircle.com/image.php?id=223149)
I routed the recess using an up spiral 1/4” cutter.
(https://www.audiocircle.com/image.php?id=223150)
I was a bit surprised to see that the exposed surface was more torn up than it was when I did the X-MTMs. It could be the quality of the MDF sold at Lowes has gone down. Yup I bought the “cheap” stuff again. But, I also wonder if the cutter has gotten dull. Probably not as it has been little used. So, I going to blame the MDF. I was able to clean this up with some light sanding. So not bad.
In the past I have used the 1/8” up spiral cutter for doing the through cuts in the the MDF as it draws less on the router’s battery. For the tweeter cutout this meant that I would use the 1/4” bit for the recess and change over to the 1/8” bit for the through cut. But this time I opted to use the 1/4” bit for everything. This worked just fine. The router has plenty of power to handle the larger bit and, with the hole being small, the battery lasted plenty long.
(https://www.audiocircle.com/image.php?id=223151)
With practice done, time to do some real cutting. All went great...
Until I noticed that one thing didn’t look like the other...
(https://www.audiocircle.com/image.php?id=223152)
Don’t ask me how this happened. I did the layout of the 2 front baffles at the same time and I used the same tape measure for both... :scratch:
But it did happen and, no, I didn’t go back and check the layout a third time just before cutting. Nope, didn’t do that.
Well, after a few choice words... :shake: I thought this would be a good time to see how good that hole cutting jig really is and I used it to cut a plug for that misplaced hole.
(https://www.audiocircle.com/image.php?id=223153)
On the first try, I achieved a plug that was almost a perfect fit. With a little light sanding, it was a light press fit to get it into place. The thing I did notice is that the router cuts holes with a slight taper. Not a lot on a 3/4” thick piece. Maybe a total of 1/64” with the 2 pieces fitted together. Not sure if that all of the pieces and parts of the router and jig being slightly off. Or is the router bit pulling everything off at a slight angle :scratch: Curious.
The plug fit nicely and a little excess glue to ensure everything got covered well
(https://www.audiocircle.com/image.php?id=223154)
I did wipe the glue off while it was still wet to make sure it didn’t affect staining later on. I re-did the layout, this time checking it against the other front baffle before making the cut. It is interesting that I found not only was the vertical dimension wrong, the horizontal dimension was wrong as well. I really missed the mark with this on.
(https://www.audiocircle.com/image.php?id=223155)
With the new hole cut, I am back in business.
(https://www.audiocircle.com/image.php?id=223156)
There is a bit of uncut material at the bottom of the holes. This is a result of the plunge cutting depth on the router being set just slightly less than the full thickness of the MDF. I do this to ensure the plug being cutout does not move while cutting it. I cut the hole in the MDF using 3 cutting depths passes so as to not overload the cutter and/or router. After I make the final cutting pass the plug pops out nicely. A little light sanding cleans all of this off.
You will also notice that the 1/8” cutter I used to cut the hole for the woofer made a much cleaner cut than the 1/4” cutter I used to cut the tweeter opening. Neither is a “cheap” cutter, with the 1/4” cutter being a Whiteside.... Hmmmm :scratch:
-
Finally I have been able to get back to these. I have pre-drilled the holes for all the drivers and binding posts screws. I did these on the drill press just because it is easy.
Next comes gluing. This is being done in steps - Sides, top and bottom first then the fronts on the X-LS. This will allow me to easily glue in the corner braces, and install the No-Rez and the crossover before I put the backs on.
(https://www.audiocircle.com/image.php?id=223783)
I use the front and back baffles as a fixtures to square the sides to the way these have been cut. I have the front and back covered with plastic film to keep them from being glued in. Each side was glued to the top and then the bottom was glued in. And, no, I didn’t forget the dowel cross side brace. This is held in place with the PL adhesive as Peter R shows in his video. The sockets for these have a lot clearance which allow the adhesive to squeeze out easily.
I could have glued the front in as part of gluing the sides, but this makes the gluing a bit less rushed.
(https://www.audiocircle.com/image.php?id=223784)
There is no such thing as too many clamps... :lol:
But there can be too much glue... :nono:
-
Looking good so far! :thumb:
-
One of the things I did on the X-MTMs was to switch out the magnetic parts from the binding posts. Yes, I know, tube connectors are the way to go. But, considering that these are going into system that is quite a ways from ideal, the binding posts with this upgrade will be fine (seem to work well on the X-MTMs. :thumb:). They can always be upgraded.... :wink:
This is what I found:
(https://www.audiocircle.com/image.php?id=217482)
And the signal path is through these magnetic parts and all of it goes through that skinny lock washer... :nono:
And I should note that the thick, spacer washer is not overly magnetic, so it is not attracted to a weak magnetic. And, while it is not directly in the signal path, I replaced it just in case it has an influence on the signal. Also note, it takes 2 regular washers to get the thickness of this spacer.
(https://www.audiocircle.com/image.php?id=217483)
The upgrade I did was to get rid of all of the magnetic parts and greatly increased the contact area to the internal wiring tab:
(https://www.audiocircle.com/image.php?id=217484)
You can see how much better the signal path is.
On the binding posts, it looks like this
(https://www.audiocircle.com/image.php?id=217485)
I bought the parts from Fastenal. While there surely are other places to get these parts, this is the order listing of the parts I bought:
1 SKU MN2530000BR0000
M4-0.7 DIN 934 Plain Finish Brass Hex Nut
https://www.fastenal.com/products/details/MN2530000BR0000
There are 2 nuts for each binding post, one each side of the wiring tab to increase the contact area.
2 SKU 75233
#8 Silicon Bronze Medium Split Lock Washer
https://www.fastenal.com/products/details/75233
There is 1 split washer for each binding post
3 SKU 0179456
#10 x 0.437" OD Silicon Bronze Small OD Flat Washer
https://www.fastenal.com/products/details/0179456
There are 2 of these washer for each binding post.
There are two of the washers needed for each binding post to replace the thick washer that is shown above. These are a spacer on the outside of the cup. The rest of the parts go on the inside of the cup.
-
Glueing the sides together went well and as I said, I remembered the internal cross brace. I like Peter’s idea of using a dowel. Also, as Peter shows in his video I used the PL adhesive to attach the dowel, but unlike Peter, I was a little excessive with the stuff... :roll:
(https://www.audiocircle.com/image.php?id=223872)
When I glued the sides together I used a plastic film to keep the front and back panels from being glued in. These panels were snug, as expected, with the front requiring a little remedial sanding to make it a little less snug to ease assembly with the glue.
As I have said before, there is no such thing as too many clumps...
(https://www.audiocircle.com/image.php?id=223873)
After sliding the glued front into place, I flipped the cabinet over so the front was down and resting on blocks. I did this so any excess glue would not run down the sides (not that i would have excess glue on a part... :duh:). One thing I found with glueing the front is that it is very flexible and that a lot of clamps were necessary to compress it evenly into the sides.
I am following Peter’s video where he describes the number of corner braces, where they go and shows how he does the installation. He uses 6 braces, 2 side to top, 2 side to front and 2 side to back. The 2 side to front don’t show up in Danny’s sketches, but they make sense given how flexible I found the front to be when glueing it. A difference is that I have left the back panel off to provide access to the interior to facilitate installing the braces, No-Rez and crossover.
For glue, I used the Titebond Quick and Thick, which, as it says, is thick and stays in place. It is also a quick set, with a bit more tack than their other glues.
(https://www.audiocircle.com/image.php?id=223874)
Following Peter’s lead, I used a spacers to locate braces, with the one for the side to top shown. The side to front braces are also shown in place. I will put in the side to back braces after I finish glueing the back in. I will have the No-Rez, which will already be installed at this point, slotted to accommodate the braces. Like Peter did, I will install them through the bass driver opening.
While glue was setting up, I took the opportunity to layout the crossover for the X-LS. Danny’s video (https://youtu.be/rIxig_9i-Iw) is perfect for this as it is exactly the same as the one I am building, which includes the “hot rod” caps he talks about. So as to not to reinvent the wheel, I followed his handy work (pun intended... :lol:):
(https://www.audiocircle.com/image.php?id=223875)
Here is mine laid out on a sheet of cardboard:
(https://www.audiocircle.com/image.php?id=223876)
Looking at it, the junction in the upper right corner is of 6 wires. I expect this will be a royal PIA to assemble.
... :P
A thing to remember is to not actually twist any of the individual wires, but to bend them together when “twisting” them together. Twisting an individual wire can cause it to break, which would not be good to have happen on these expensive parts.
-
With that knot of wires in the tweeter circuit, I decided to buy a new soldering iron; a Weller 40W. This is quite a step up from the 25W one I have. Wow, does it get hot. But it works.
Soldering went well. The two X-LS crossovers are assembled. For that knot of wires in the lower right of the crossovers (as shown) it turned out that I could join the 3 wires of the 2 caps and the coil together, then join together the 2 long pigtails from the brown caps and then join together the 3 wires from the 2nd brown cap, the small white cap and the resister. Not a big knot at all.
(https://www.audiocircle.com/image.php?id=224192)
I am pleased with the way they turned out. The boards are 1/4” lauan that I have coated with shellac. I added a 1/4” high rest for the lead-in resister in the tweeter circuit. I added a thin wood strip for under the tweeter circuit coil because the last winding layer is less than the full width of the coil and this will allow it to be mounted fully upright. The wood I used is from a quart can paint stirrer.
I plan to mount the boards on rests that will raise them about a sheet of No-Rez on the bottom baffle. I know, this is more than what is called for, but it will allow me to screw the mounting screws into a piece of wood that is above the MDF and the No-Rez will add more dampening to the cabinet. The downside of this is that I will need to buy another sheet of No-Rez. The X-LS can be lined with one sheet of No-Rez without this extra piece I am doing... :roll:
(https://www.audiocircle.com/image.php?id=224193)
I just need to cut the pieces of No-Rez for the back panels.
Because I am working with the back off, the No-Rez pieces can be larger and the cutting is simplified. The side pieces are cut with about 1/2” space to any side and about 1/4” space to the internal braces. The top, bottom and back pieces are cut about 1/4” less than the width between the side pieces of No-Rez.
Of course the contractor making these didn’t have a contract penalty clause for not meeting the required delivery date and let other priorities take over. That date pasted without having a completed birthday present :cry: and I was left with having to apologize profusely to my daughter for having missed her birthday. None the less, she got to see a preview of them the other day and she is extremely excited about the prospect of having them. She is great and is very understanding about those other priorities. I promised her they will get done...
-
Excellent write-up. I am on the verge of purchasing an X-LS kit, and your post will be very helpful!
Thank you
-
Ok, don’t do what I just did... Cut the wires to the tweeter a little to short... :duh: 3 more inches would have been great. Oh, yah, there are about 5” of each color laying on my work bench. So, there was enough. Danny doesn’t short you on wire, but then again, there is not a lot of excess. So one needs to not over do it, but then again one doesn’t need to scrimp... :nono:
Well, it will do. The wires will reach out of the hole for the tweeters, just by not a lot.
The other thing I didn’t realize at the time was where was the best location to put the recess in the the tweeter opening to make way for the driver’s terminals. I put mine 180deg from where they would be ideal. So I will route in another set on the other side of the opening before putting anything more into the cabinet. Not sure how I would have avoided this situation except to have laid out the crossover much before this point which would have showed me where the wires would be best positioned. In this small box it makes a difference, whereas in the X-MTMs, with its size, it wasn’t a consideration. Something to remember for the future.
One thing I did do was to label the wires...
(https://www.audiocircle.com/image.php?id=224260)
Yes, I need a few more labels... :wink: The shiny white stuff is dry erase board and the tape barely sticks to it, which is nice for doing this...
With the crossovers boards all mounted with parts and all tired down, it is starting to look like a set of speakers.
(https://www.audiocircle.com/image.php?id=224261)
The crossover boards are setting on the stand-offs to allow No-Rez to be located under it. The board does come close to the woofer, but the parts are more than an inch away from it.. The other thing I realized is that if the larger coil were to be on the other end of the board it would be directly under the magnet for the woofer and I would be willing to bet this would not be good for the speaker’s sound quality. :shake:
-
It is tough getting one thing done when there are other equally fun things to do... 8)
But that doesn’t mean nothing has gotten done on the X-LS cabinets. Quite the contrary. As you may have observed the back panel has been left off. I have done this to facilitate the installation of the internal side/corner braces, the No Rez and the crossover. This has worked out well.
(https://www.audiocircle.com/image.php?id=224942)
The standoffs for the crossover are just high enough for the crossover to fit above the No Rez and provide a nice wood piece to screw into. This also adds another baffle that is padded and acoustically dampened. The woofer does clear the crossover, although it is close and care needs to be taken in locating the crossover, as there is not much room and it touches the No Rez on the back panel.
(https://www.audiocircle.com/image.php?id=224944)
The back panel No Rez was placed on the back panel by first dry fitting the back panel onto the the rest of cabinet. Then the back panel No Rez was slipped in through the woofer opening and stuck to the panel. This way it could be easily located between each of the side pieces. Once it was stuck in place, a gentle push from the inside on the back panel and it popped out.
Next came the installation of the crossovers for real this time and the back panel was glued into place. Actually, just before I did that, I put tape over the driver openings on the inside of the front baffle. This will keep any dust and other stuff out of the inside while I finish the outsides. The openings on the back panel are covered by the No Rez.
Oh, what about the braces from the sides to the back? Those will be one of the last things to glue in, just before the drivers are installed. There are cutouts in the No Rez for this already... Now I just need to not forget to do this... :roll:
(https://www.audiocircle.com/image.php?id=224945)
With the back baffle glued into place and all of the openings taped up, it is time to trim the edges. If anyone has not caught Peter’s recommendation, this is done with a down spiral edge trimmer on the router. Easy.
(https://www.audiocircle.com/image.php?id=224946)
Next came sanding of the trimmed edges to clean up any high spots and glue drips not cleaned up by the router. This random orbital sander is the best! Look Ma, no cords. I did make an adapter to attach it to a vacuum hose. This thing creates a lot of dust. While it has a really good dust collection system and bag, the bag to tool seal is not the best. Most cases it is “good enough”, but for the MDF in a closed basement, the vacuum seemed like a smart thing to do.
I know, the X-CS has been left behind. Yup, but don’t fear it will get done. I am enjoying the X-MTMs so much by themselves that I forget that this system will be further improved with the completion of this and a set of rear channel speakers. :green:
-
Work on the X-LS is continuing, admittedly slowly.
After an initial sanding, I rounded the front and side corners with a 1/2” quarter round. Then another round of sanding. From there it is finish the finish... I did the same uninspired finish that I did on the X-MTM. This is a layered up stain with several layers of varnish over that.
On the X-MTM the layering of the stain went reasonably well. However the varnish was a problem. As soon as the varnish was put on it would start to setup. It was hard to even out as a result and it would have sags and runs as a result.
With the X-LS cabinets, I had the added complication of the stain formula having been changed by MinWax and it is now much thinner. The end result is that, even though it is still oil based, it reacted with the wood shreds of the MDF in much the same fashion as water would do. The “grain” of the MDF was raised up and ruined the nicely sanded surface. Because the stain becomes gummy when it dries, there is no sanding it before applying the varnish. I finished the layering of the stain with the rough surface. After the first application of varnished I heavily sanded it to remove the high spots, but not so much as to remove any of the built up stain. It took about 5 layers of varnish and sanding to get an acceptably smooth finish.
At least the finish on one cabinet was acceptable; the other not so much. The other cabinet had sags, runs and missed areas... Why? I am not sure. I did both at the same time and they were both sitting next to each other. Maybe I rushed on the second one... Don’t know.
I have heard that the definition of insanity is doing the same thing over and over again and expecting the result to change. I got that feeling in trying to get an acceptable finish on that second cabinet. Every time I thought I had it right, I would find something... Whether is was sags and runs or missed areas, for some reason there would be something beyond something that which I could accept... I probably did 5 or 6 more layers on it before it was acceptable... Insane... :evil: Even when done it seems that there will always be something. In this case the cabinet that has the all of those layers of varnish is slightly darker that the other one... :duh: There is no going back at this point... :wink:
On the plus side I found a few things that worked well for me. 3M makes a foam sanding block. This is great for nocking down high spots and getting a smooth finish, but it is flexible enough to do the rounded corners. The extra-fine worked best for this. I followed this with a steel wool buff, vacuumed off the dust and wipe it down with paint thinner. After a short drying time, applied the next layer of varnish. Another thing that worked for me was to apply the varnish with a piece of terry cloth. It was much easier than a brush to get an evenly thick coating and to get a thinner coating that didn’t sag or run. The downside was that it was very prone to picking up stray hairs and whatnot.
With respect to the stain, I found out after having the problems that MinWax now requires the application of a wood pre-treatment that they make. I am guessing that might have prevented the problem I had with the raised grain. I will need to experiment with this before doing the finish on the X-CS.
The other thing I am thinking of doing is thinning the varnish a little with paint thinner to see if that helps to slow it down from setting up. Again, another experiment.
As for my final finish, not the best picture, but an acceptable result...
(https://www.audiocircle.com/image.php?id=225823)
The best part is that my daughter, who will be getting these, is thrilled with the way they look... :green:
And like me, she is more interested in the way they will sound than looks. So, that is all that counts.
Just a little more to do on them. Pull the tape off the driver openings, cut the holes in the No-Rez where the ports and binding post will go, install those, solder the wires to the drivers and install them...
I hope to be done by Xmas... :lol: :lol: :lol:
-
Finished the X-LS speakers...
Once the exterior finish was done I had a few things left to do.
Because of the assembly sequence I used was to put the back on last, the braces for the back needed to be put on after the back was on. This meant reaching in through the bass driver opening with the diagonal braces with glue on them. To facilitate this, I used the Titebond Quick and Thick glue. The glue sets fast and, being thick, the piece being glued may be assembled less than perfectly.
(https://www.audiocircle.com/image.php?id=227698)
It is tight, but my skinny hands fit... :green:
Next I found that one of the caps was “loose” on the board. So I used some Loctite mounting putty to secure it. I probably should have checked this more closely when I assemble the crossovers. But this will keep it from buzzing or rattling. I probably should have put a 3rd zip tie around all of this. Something to consider in the future.
(https://www.audiocircle.com/image.php?id=227696)
(https://www.audiocircle.com/image.php?id=227697)
The ports were next. I used PL adhesive to mount those.
(https://www.audiocircle.com/image.php?id=227695)
The port openings were a little oversized, so the thickness of the adhesive worked in my favor.
Soldering of the drivers went pretty well. The 2 issues I had were... I could have cut the wires to the binding
a little shorter and made the wires to the drivers a little longer. Maybe an inch less on the one to give a half inch to each of the others.
The other issue was soldering iron heat. My 25w one was not hot enough and the 45w one was too hot and the solder would oxidize quickly, in particular on the smaller tab, which made it hard to make a good joint. I will be looking into something different to do this on the X-CS when I get to it.
However, with that done, the drivers mounted easily and this is the finish product...
(https://www.audiocircle.com/image.php?id=227694)
I did a sound check on them and they sound really good. Just to note, the binding posts have been upgraded to all non-ferrous parts. I used these as I am unsure as to what my daughter has to hook up to them. These will make that simpler for her.
Now, I am off to deliver them... Daughter is very excited... :hyper:
-
They look great Jon! I’m sure your daughter will enjoy them for years to come.
-
Thanks :thumb:
They have been a long time in the making...
And a little past her birthday. But she has been good about waiting.
-
great job, well documented... very useful. hope i can build mine in the future. still working the budget phase. ( lacking the budget)
-
Hi once again.
Happy New Year to all.
Sorry for the long hiatus, but this project needed to be put on the back burner for other things. But I am back and looking forward to completing the X-CS.
A quick update on the X-LS speakers I gave to my Daughter. She has reported back that they are unbelievable. Her and boyfriend watched Dune and played the audio through these. They were both blown away by how good and transparent the sound was. So - Success.
Maybe a little bit of the reason work on the X-CS has languished is because the X-MTMs I am using just in stereo mode are so freaking good... Wow... They never cease to amaze me.
But, enough about that. I am once again actively woking on the X-CS. Previously I got to the point where I needed to assemble the crossover. Danny has a great video showing how to do this so I won’t bore people with the details of that. So the next step is the board for it.
(https://www.audiocircle.com/image.php?id=234578)
One of the things I did on the X-LS speakers was to mount the crossover board on standoffs to place it above the No-Rez. This way the bottom of the speaker can be dampened with No-Rez with the crossover out of the way.
The board is 4.5” x 9.5”, 1/4” lauan which I covered in shellac, well, just because I like the way it looks. Holes are drilled in it for the tie downs for the electronics and for the mounting screws. I also added some stand offs for the 2 resisters in the crossover. The stand off for the tweeter out resister is oversized so I can fix the driver wire to it and not have to rely on the thin resister wire for support.
As noted early in this thread I modified the internal outboard braces to be like the braces in the X-MTMs with the idea that they would provide additional rigidity to the cabinet. My initial concern was whether I would be able to mount the crossover in the remaining space. No problem and it will fit through the base driver opening.
(https://www.audiocircle.com/image.php?id=234579)
Here it is with the crossover in place:
(https://www.audiocircle.com/image.php?id=234580)
Note that I have it place as far back in the space as reasonable in order for the in-put wire to clear the left hand brace. One of those wires will attach to the resister on the left side of the board and both will need clearance to bend around to the back of the cabinet.
I glued the crossover standoffs to the MDF using Titebond Quick and Thick glue. It is thick so it doesn’t run when tuning the board over to put it in place and it is less particular about gaps than the other glues. By attaching the standoffs to the crossover board first, then glueing them to the cabinet, it will be easy to reattach the board once the electronics and wiring are on it.
I did do some “creative” clamping while the Quick and Thick glue setup... :green:
(https://www.audiocircle.com/image.php?id=234581)
More to come... :thumb:
-
I got the speaker driver wires soldered to the crossover. On of the things I did was to start with a single base driver wire to attach to the crossover. Then I paralleled in a second wire a few inches up, make the remaining length of the 2 wires about the same. I did the same with the negative side wires. But for the negative wire, the “single” wire I started with is the wire from the crossover to the binding post. Then I parallel in the wires from the base drivers and then the wire from the tweeter. I did things this way as I found that it was hard to deal with more than 2 or 3 of these heavy wires twisted together.
This may not be the best picture to show the wires and how they are joined together, but it does show the base side of the circuit and how the wires are paralleled.
(https://www.audiocircle.com/image.php?id=234729)
The other thing I did is to make a strain relief for the thin wire coming out of the resister for the tweeter + side wire.
(https://www.audiocircle.com/image.php?id=234730)
I used the table saw to cut up the No-Rex. I have a well used (read - “somewhat dull”) blade I use for this as the No-Rez backing is pretty abrasive and no point in wearing out a good blade.
(https://www.audiocircle.com/image.php?id=234731)
And here is the No-Rez notched for the crossover board stand offs and the center strip notched for the braces. There are 3 pieces of No-Rez for this; the seams between the center piece and the other 2 pieces is hidden by the braces.
(https://www.audiocircle.com/image.php?id=234732)
-
I installed the No-Rez everywhere except on the 2 sides where it would hinder my access to the location for the braces between the sides and top. Note the layout lines for those braces.
(https://www.audiocircle.com/image.php?id=235214)
I mounted up the crossover in preparation for glueing the top panel on. While routing the wires in the cabinet, I found that the + wire for the tweeter was short. I was hesitant to try to unsolder the wire on the resistor and solder on a longer wire for fear of breaking the resistor’s wire. While ponder this I took a closer look at the layout on the crossover board and realized that it made little sense to have the capacitor located so the wire coming out of the resistor is pointed to the back of the cabinet, not the front.
An easy fix... cut the zip ties to the capacitor and resistor and relocate them. I also had to remove the support for the resistor. Ok, this works better...
Previous arrangement with the short + wire...
(https://www.audiocircle.com/image.php?id=235216)
New arrangement. Note I kept the support for the resistor and the tie down for + wire itself
(https://www.audiocircle.com/image.php?id=235217)
I did have to do some custom fitting of the top. Even though I had the top in place when I glued the sides and back to the bottom, the top was now fitting a little less than square.
It is hard to see in this picture, but the upper righthand corner of the top sits proud with respect to the end of the side.
(https://www.audiocircle.com/image.php?id=235213)
My fix was to trim the edge of the rabbit on the top to make it a hair less square so the front will fit. The “unsquare” parts will now hang off the back and sides which will be trimmed later, so not an issue.
Back to reinstalling the crossover with the new arrangement. I used a little of the mounting putty to secure the screws from backing out. This is nonhardening so the screws can be removed easily at a later time if needed.
(https://www.audiocircle.com/image.php?id=227696)
I just put a little into each screw hole.
(https://www.audiocircle.com/image.php?id=235215)
There is a small gap between the top and the braces. This was intentional so the top would sit flush on the side and back panels. To attach the top to the braces I selected the PL adhesive. This does well at filling gaps and should keep it all secure. The other option would have been to use the TiteBond “Quick and Thick” which will also fill small gaps, but I thought it might run a bit before it set. Other than that I think either would be acceptable.
PL adhesive on the braces. In hindsight, I should have used a bit more to ensure full coverage, but this was enough to make it secure after all had set up.
(https://www.audiocircle.com/image.php?id=235218)
Clamping. Never enough clamps. For this type of glueing I use the Titebond Original. I did put a little glue on the ends of sides and back panels just so the open grain didn’t suck up the glue off the top and cause it to setup too quickly or not be enough for coverage. Ok, maybe I put a little too much on, had a few runs, but all is good.
(https://www.audiocircle.com/image.php?id=235219)
Note the binding film around the front panel. This is to keep glue from sticking to the front which is only in place to ensue the top is located properly. The front will be glued on later...
Oh, I did remember to put the No-Rez on the top in the proper locations before glueing the top on. Smart, so I didn’t have to fuddle with doing that after the fact.
-
After I glued the top on and pulled the front off, I realized that I had not tested out the crossover...
:duh:
I figured that now was now or never to do that, since the front was still off and the crossover could be (with some difficulty, removed. But it would not be as hard now as it would be with the front glued in place....
So I got out my trusty test rig I used before...
(https://www.audiocircle.com/image.php?id=235635)
Which now supports a set of very sophisticated Harbor Freight multi color test leads with alligator clips. They are cheap and work, much like their clamps I use. What’s not to like about these... :green:
The sound check went well...
(https://www.audiocircle.com/image.php?id=235636)
Next was glueing the remaining diagonal braces in place. Titebond Quick and Thick works well for this.
(https://www.audiocircle.com/image.php?id=235634)
I let that set up for 24hrs before glueing on the front. But first, the holes for the drivers were taped off on the backside to facilitate the remaining work of sanding, routing, staining and varnishing.
(https://www.audiocircle.com/image.php?id=235637)
As I did for glueing the top panel, I spread a thin layer of glue (Titebond Original) over the end grain of the MDF that makes up the top, bottom and the 2 sides, as well as on the rabbited area on the front panel. Then well-clamped the assembly.
(https://www.audiocircle.com/image.php?id=235638)
Once the glue is well setup, the cabinet will be ready for finishing.
-
I am pleased with the way the gluing ended up. The joints are all tight. The next step is to round the edges. One of the things that Danny talks about is corner distortion from the front baffle and from sharp edges in a grille. I have not been putting grilles on the speakers I have built, so rounding edges seems to be the right thing to do.
(https://www.audiocircle.com/image.php?id=237138)
All sanded and ready to go. Note the tape covering the back side of the driver openings. I did this for the binding posts also.
One of the things I found when applying the finish to the X-LS speakers is that the MinWax stain appears to have had a change to its formulation. I have been using a layered up stain on the cabinets. This has been 3 or 4 coats of stain on the MDF with a day or 2 of drying between coats. This worked really well on the X-MTMs I built. But for the X-LS speakers, this didn’t work as well. The stain was thinner and didn’t layer up as well. I also noted that MinWax has added a preconditioner to the staining process. I didn’t use this for the X-LS cabinets, but decided to use it for the X-CS speaker.
The result was dramatic. I applied the MinWax preconditioner to the left side of this test piece and no conditioner to the right side. The difference is noticeable; the left side represents the result I am looking for.
(https://www.audiocircle.com/image.php?id=237139)
But one thing I noted was that the preconditioner and the stain substantially raised the “grain” of the MDF more than what I saw on the X-MTMs where I used the older formulation of the stain.
I figured that I could work out the raised MDF “grain” on the actual cabinet with a Scotchbright pad. I did this with moderate success after applying the second coat of stain on the cabinet. It turned out that the 3rd coat of stain raised the high spots that I had thought would not be an issue. Then I thought this could all be smoothed with a layer of varnish and sanding...
Well, you likely have guessed where this is going... That didn’t work so well... The sanding smoothed it, alright. It also cut into the stain... :duh:
Fortunately, this isn’t as bad as it could have been. The spots where the stain was cut away are small. A while back, in a response to a post of a similar issue, the person noted that there is an Eastern philosophy of embracing the “defects”. I think will run with that... :thumb: I’ll let you know how that works out.
-
Minwax makes both water-based and oil-based stain. I wonder if that would explain some of what you experienced. Photo of can or recommended clean-up solvent would tell at least some of the story.
Pre-stain is usually just stain base with no pigment added, although marketing would lead one to believe it's got some magic in there too.
-
Ya made me look... :lol:
Really, that thought crossed my mind about it maybe being water based. The MDF does respond as if water was being put on it. But, no, the stain is clearly marked as oil based. I wonder if they changed the solvent in the stain and it now attacks the binder use in the MDF? As for the preconditioner, I think you are probably right. The older stuff didn’t mention a preconditioner. So I wonder if that is something that was removed and put into a separate can. Don’t know.
I would suspect this change has something to do with pollution regulations. I know, it’s a pain, but I believe it is necessary if it is. I will figure it out. So far, what I have done (more to come on that) seems to be working out. I also noticed a hint on the new can that may have made a difference for me. They recommend doing a second coat of stain within 2 hrs if a “richer” look is desired. That might be something to investigate my next pair of speakers (yup, more to come) vs waiting a day or 2 between coats as I have been doing.
I happened to have an old can of the stain (on the left in the picture) laying around.
(https://www.audiocircle.com/image.php?id=237143)
Interesting thing I just noticed is the new can doesn’t say how to do a cleanup... :scratch:
It does now warn to protect against spontaneous combustion of rags and the like that are soaked with the oil.
As for the stain itself, another thing I noticed is that it no longer settles out like the old stain did. Or at least no where as much as it used to. Less stain solids?
Just a general comment... I know there are other brands of stains out there. Thing is, I started all of this with this MinWax stain and I would think that some other brand might be a slightly different shade even though it says it is the same color. Also, I am very familiar with the way this brand performs (the devil you know). A different brand would be something new to figure out... Changing at this point would likely not be ideal.
-
Above I said “more to come”...
At that time I had started my process for “correcting” the cut-through that the sanding had done. I held off saying anything until I had some results.
The results are in and I am going to decree success... :thumb:
What I did was to apply a layer of stain over the sanded varnish. I allowed this to dry for a day, which left the stain tacky. I then applied a coat of varnish over that. This was the result...
(https://www.audiocircle.com/image.php?id=237337)
If you look closely you can see the sanding scratches and uneven coverage of the varnish. But, hey, this is a process and at this point I was just happy that the varnish stuck and hardened over the stain that I had put on.
I used 3M foam rubber sanding blocks for smoothing out the finish. One of things that I have been dealing with all along (including the earlier X-MTM build) is the varnish sagging on vertical surfaces when applied with a brush. :shake: But, using a brush makes it easy to get a couple of “thicker” coats on that can than be sanded down smooth over the “rough” MDF. A “fine” 3M sanding block works well for this. An issue I have with the “fine” sanding blocks is that they have random grains that are larger than those making up the rest of the block. As a result it leaves random scratches that I have to deal with, which can be seen in the picture.
To get thinner coats of varnish on, I use a piece of terry cloth. Yup, I have to deal with the random piece of lint, but that is easier to deal with than the sags. I minimize the lint by going over the cloth with a big piece of masking tape. Why not just apply a thin coat with a brush? Well, I find that varnish starts to setup too fast to brush it out to a thinness that won’t sag. When it starts to set up, the brush then leaves brush groove streaks, along with sags. No winning with a brush for me for that one. Maybe it can be done, but I don’t know how...
After the first thin coat of varnish dries, it gets hit with an X-Fine sanding block. Not sure why, but no significant scratches from these. That is followed by some 00 steel wool. That is followed by another thin coat of varnish followed by 000 steel wool and another thin coat of varnish and then repeat this last step at least once.
At this point, I am done. That is, as long as I don’t find any missed spots. If I do, than it is the last step all over again. When it is “good enough”, this is what I get...
(https://www.audiocircle.com/image.php?id=237338)
I know, boring and somewhat less than at the “Steinway” level of perfection. But, the whole idea of this finish is for the speakers to disappear in the room (I’ll blame the wife for that one... :o :lol:) and these will be in a dark end of a dark room. The imperfections just add character, if they can be seen at all :thumb:
I am happy now to move on to the final step... Hooking up and mounting the drivers.
-
The imperfections just add character, if they can be seen at all :thumb:
That's half the fun of DIY projects is learning new skills and adding your own flair to the finished product. Even if it does result in a few $ contributions to a swear jar. :thumb:
-
You are right.
What’s the saying? ... It’s the journey and the destination.. :wink:
:thumb:
-
Looking good.
-
Looking good.
Thanks... :thumb:
I had told my Wife about the issues I have been having with the varnish sagging. So when I showed her the cabinet, she already knew that there would be something in particular to look for. After looking at it for a little bit, her comment was:
“So, what am I supposed to be looking for?” :oops:
I guess that answers my concerns about how it looks.... :wink:
IMHO the cabinet looks really good and will match well with the X-MTMs.
Time to get onto soldering the wiring to the drivers and get this bad boy hooked up...
-
The X-CS is finished! :dance:
And up and running:
(https://www.audiocircle.com/image.php?id=237979)
Overall, it is definitely worth the effort...
My overall impressions... It is tough to compare this center channel to the X-MTMs. The X-MTMs are so transparent and have such a wide range. It was even tough to tell which speakers were playing; the X-MTMs in 2 channel or the X-CS in 5 channel produced the identical location for voices. That surprised me. The speakers are well matched for that. Where the difference comes in is the range. As expected the X-CS drops off in the low end at a noticeable higher level. Voices are the same, but there is a difference in the level of sounds, other than voices, that come through... Now, I will admit, this could be a difference in the way the AV receiver divides the sounds between the channels and the fact my 2 rear speakers are pure crap... :roll: and I was only playing broadcast TV and not an action movie DVD or the like. So, this may not be the fairest of comparisons...
If I back pedal to what I said about the center voices, the X-CS is truly up there and worthy of being paired with the X-MTMs... :thumb:
Once I got past the idea of needing to perfecti the finish on the cabinets, I moved onto the soldering of the wires to the drivers and binding posts (yes, I know, tube connectors... Later dude, cables and better AV recover first), and installing the drivers and binding posts into the cabinet. The soldering went well. Actually easier than on the X-LS or X-MTM speakers... Why? I don’t know. I know how to solder. I have done it for years. Maybe I just took more care this time when I tinned the wires and posts on the drivers. I also had a higher wattage soldering iron... that could be it.
The completed speaker looks great:
(https://www.audiocircle.com/image.php?id=237980)
(https://www.audiocircle.com/image.php?id=237981)
The speaker will be on a glass shelf, so I added thick felt feet to the underside:
(https://www.audiocircle.com/image.php?id=237984)
I did the same to the underside of the TV base. I figure with these there will be little chance of there being buzzing or rattling between these pieces.
I did find I made 2 small errors when I glued on the front baffle. The first was not outlining (marking) the locations of the ends of the 2 center braces on the inside of the front baffle. As a result, the tape I used to seal one of the driver openings got stuck between the end of the brace ends and the front baffle. Not a big deal as it probably “fixed” the other error I made. That is, I forgot to put a dab of glue on the ends of those two braces... Given how close they are to the front baffle I was wondering if they would buzz as a result of missing the glue. From what I can tell, no buzzing...
Well, surely there can be no buzzing where the tape is stuck in. Lucky fix:
(https://www.audiocircle.com/image.php?id=237982)
At least for the 2 ends of that one braces.
But, I was not so lucky with the other brace. The tape didn’t get into that area, so, hopefully, the ends are tight up against the front baffle.
(https://www.audiocircle.com/image.php?id=237983)
After thinking about it for a bit, I figured this will likely not be an issue at all. The other thing I came up with is that I would have been better off just cutting these two braces 1/8th inch short. If they were glued, they would provide little if any support to the front, so a space shouldn’t affect the end result. A space would then make the build slightly easier with not having to deal with my 2 errors and in not having to be precise in their overall length. Something for the next time.
I hope this was an interesting adventure for everyone following... I know, I enjoyed it. :thumb:
Now off to do a set of rear speakers, a set of rear speakers... X-Omni? Yes, I think so. They should do nicely in the room I have... Now, just waiting on parts... :popcorn: