AudioCircle
Industry Circles => GR Research => Topic started by: jimbones on 4 Jun 2017, 07:07 pm
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Here's a build thread on my latest project. The system is built around the 2x12 OB H Frame with Rhytmik XO-amps. I have designed the uppers using the Satori MW16P and TW29R. I may eventually go to a MTM set up on the uppers.
I have called it Open Aire because they are full open baffle and Aktiv since the woofer section is using an active crossover and is bi-amped. However, I am not using active XO or DSP on the top.
Life got in the way so I had a local cabinet maker build the raw cabinets. Later I brought him Tineo veneer and thats where I took over.
(http://www.audiocircle.com/image.php?id=163353)
(http://www.audiocircle.com/image.php?id=163354)
(http://www.audiocircle.com/image.php?id=163355)
(http://www.audiocircle.com/image.php?id=163356)
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Here is a before and after sanding sealer.
(http://www.audiocircle.com/image.php?id=163357)
(http://www.audiocircle.com/image.php?id=163358)
(http://www.audiocircle.com/image.php?id=163359)
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Fort the first time since I can not remember when we had a nice weather day in NY. It has rained everyday and is still in the 50's here. So 70 and dry was perfect for spraying. I did the inside of the cabinet satin black and gloss lacquer on the outside.
(http://www.audiocircle.com/image.php?id=163360)
(http://www.audiocircle.com/image.php?id=163361)
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Well done! I have to say that Tineo veneer is really handsome. I'd never even heard of it until Jay posted about using it.
Thanks for posting your progress, I really enjoy seeing other peoples projects and hope it encourages others to do same.
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Well done! I have to say that Tineo veneer is really handsome. I'd never even heard of it until Jay posted about using it.
Thanks for posting your progress, I really enjoy seeing other peoples projects and hope it encourages others to do the same.
Peter, your project going right now is absolutely mesmerizing, I really enjoy the thinking/working out side the box on your finishing designs. The finishing processes you are doing inspire open thought and are fun to be a part of.
jimbones, the Tineo veneer in really striking especially with the continuation of the grain.
I don't post as much as I should on these build threads but I really enjoy them more than just about anything else.
Thanks guys.
Greg
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Peter, I'd like to see the project that you are working on, can you share the link or key search word?
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Hi Jim, I'm guessing you found a sand filled sub build? Only one I remember posting about cutting and buffing, but that would have been automotive urethane.
Lots of info on the web. Unfortunately some is utter crap.
I'll tell you what I know.
I think the Behlen lacquer is nitrocellulose (often called simply nitro). Nitro has some great properties for speaker finishing, less so for other things because many modern finishes are catalyzed which adds speed to curing and enhances durability. In a production setting, the speed is important. A project like yours, patience will be your friend. Simply put, a good finish takes time, both for curing and "finishing" the finish.
It can be sprayed coat after coat without much concern for total film thickness. That's the plus side. The down side is because it's not catalyzed, it takes a long time to really cure hard enough to really work with a buffer. I'd probably wait a month after last coats...longer if it's possible.
I don't know the grain structure on Tineo never having used it, but a really smooth, flat, high gloss "piano" finish requires grain filling. That can be accomplished with lacquer, but the process is long with nitro...it just doesn't have the body and solids content that is present in commercial finishes. Spray, sand flat, spray, sand flat, lather, rinse repeat...more times than many have patience for.
Jim, you should understand that I differentiate between a high gloss finish and a "piano" finish. First will show grain when looking at it with glancing light. Piano is like glass...absolutely flat.
I think the biggest problems people have spraying finishes in general is not getting wet coats and not taking enough to complete. We're just accustomed to rush, rush rush, but I suppose that's touching on a personal philosophy of mine. With most finishes, the ideal would be a film thickness that's just shy of running and sagging. A hard thing to accomplish. With nitro though, if you get a run, it can just be sanded flat and recoated.
Excluding a lot of variables your finishing schedule might looks like this.
Sand what you have FLAT with a hard rubber block or similar.
Repeat process a few times. You need a significant film thickness to be able to sand and buff.
Once you've got it where you want grain fill wise, set it aside for a few weeks, then cut and buff. Enjoy the journey! I remember reading a long time ago that finishing is the boondoggle of woodworking. We tend to rush the very thing that will be most visible in the end game.
If you're a reader, I'd recommend "Understanding Wood Finishing" by Bob Flexner. Probably the single most informative reference I've encountered. Demystifies a lot of finishing folklore, I still refer to it now and then even though I've probably had it for 20 or more years.
Also some good finishing info from Jeff Jewitt at Homestead. http://homesteadfinishingproducts.com/
You could also look at the wood finishing forum on Woodweb, but it's primarily pros using products the DIY market never sees, plus there's folks there that seem to patrol for DIY's so they can scare them away.
Hope that helps you out. FWIW, I prefer to have this info "in thread" so everyone reading can potentially benefit. Feel free to cut and paste in yours if you like.
Best, Peter
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The above was a discussion I was having with Peter regarding Piano finish. I have a dilemma as my original plan was piano finish but now I am starting to like what I see. There may be more risk in messing with finish.
(http://www.audiocircle.com/image.php?id=163421)
This is a photo of the finish without touching it. I almost tempted to leave it as is. Opinions?
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The basic rule I've always heard is when you are satisfied with the finish, it's done.
I can't come close to a piano finish with a spray gun. Satin, semi-gloss or gloss yes but that's it for me with spraying.
Up close and personal the speakers in my avatar do look very close to a piano gloss but that finish is not sprayed. It is a hand rubbed shellac in a style known as French Polish. Basically hundreds of microscopically thin coats of shellac built up in bodying sessions with rubbing out sessions between every three to five bodying sessions.
But as Peter said, this level of finish takes a lot of work. It took me three months of nights and weekends to get to this level. Even then, with French Polishing the stopping point is when you are satisfied with the depth and luster of the finish.
Mike
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Jim, there's a common thought that more coats is gonna smooth things out. And that's true to some degree, but mostly it's the sanding between coats that makes a finish look good. The first coats I'd consider sealer. It locks the hairy wood fibers in place and preps them for sanding flat.
Showing the grain isn't a bad thing, it's just a different look. Filled finishes look nice to my eye because I appreciate what it takes to get there. In many cases though, it also robs the wood of an organic feel that I also like. High gloss used to be the benchmark of good furniture, but it tends to obscure grain because of reflective surface. Duller sheens are prevalent now.
Were I to advise you, I'd suggest sanding what you've got flat with 220 or so to remove the hairy grain and then reshoot a few coats. Let that dry a few days and rub out with 0000 steel wool and lubricant...you want lubricant but it's often overlooked. Wool Lube is one I have on hand.
You're just a kiss away from something I bet you'd like even more.
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Jim, there's a common thought that more coats is gonna smooth things out. And that's true to some degree, but mostly it's the sanding between coats that makes a finish look good. The first coats I'd consider sealer. It locks the hairy wood fibers in place and preps them for sanding flat.
Showing the grain isn't a bad thing, it's just a different look. Filled finishes look nice to my eye because I appreciate what it takes to get there. In many cases though, it also robs the wood of an organic feel that I also like. High gloss used to be the benchmark of good furniture, but it tends to obscure grain because of reflective surface. Duller sheens are prevalent now.
Were I to advise you, I'd suggest sanding what you've got flat with 220 or so to remove the hairy grain and then reshoot a few coats. Let that dry a few days and rub out with 0000 steel wool and lubricant...you want lubricant but it's often overlooked. Wool Lube is one I have on hand.
Peter, you nailed it. I was thinking that as much as I want to get that glass finish something was artificial about it. But you use the term organic which is exactly what i was thinking but couldn't communicate. I can tell you I dont see any hairs on this, it is smmooooooottthhh. Now I can probably get better if I sand and reshoot as you say. I read on woodweb to use Murphys oil soap and water as a lube.
You're just a kiss away from something I bet you'd like even more.
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Man, those are beautiful.
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I missed this thread but, they look great jimbones.
I agrree with Peter, if you want a perfectly flat surface, block sanding and multiple klight coats ... keep taking the high areas off.
Personally, I kind of like the grain showing through a bit
jay
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Thanks for the advice and words of encouragement. I have decided I am going to sand down and shoot again. I will not be doing the "piano" finish. As pointed out having the grain come through a bit is a nice touch.
Now a bit of mystery :lol:
(http://www.audiocircle.com/image.php?id=163548)
(http://www.audiocircle.com/image.php?id=163549)
What could these be? stay tuned.
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Let's see. A pencil, a cast iron saw table, some primed wood things. Do I get a prize?
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ha ha ha. want to try a design detail, not sure it will work but if it comes out the way I want it to I think it will be nice. :lol:
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ha ha ha. want to try a design detail, not sure it will work but if it comes out the way I want it to I think it will be nice. :lol:
You and Peter sound like kindred spirits :thumb:
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(http://www.audiocircle.com/image.php?id=163782)
I toof Peters advice ands sanded with 320 and shot more lacquer. I feel it came out flatter and more consistent. Thanks Peter.
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Those are gorgeous Jim, love that veneer.
Best,
Ed
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(http://www.audiocircle.com/image.php?id=163783)
Starting grill frames
(http://www.audiocircle.com/image.php?id=163784)
bases
(http://www.audiocircle.com/image.php?id=163785)
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you do good work!
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you do good work!
Thanks Bob, It's really a labor of love. Lots of labor, lots of love :lol:
I am still at the beginning and have quite awhile to go.
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OK so more sanding with 1000 grit and more coats and I am now done with the cabinets. I think I struck a good balance between the "organic" look peter was talking about and the gloss i was looking for. They actually look wet :lol:. I am making more progress on some other design elements and will post more pics soon.
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A lot of work up til now has not been sexy at all. Lots of prep work before anything gets assembled. worling mainly on grills and base here.
(http://www.audiocircle.com/image.php?id=164483)
(http://www.audiocircle.com/image.php?id=164484)
(http://www.audiocircle.com/image.php?id=164485)
(http://www.audiocircle.com/image.php?id=164486)
(http://www.audiocircle.com/image.php?id=164487)
(http://www.audiocircle.com/image.php?id=164488)
(http://www.audiocircle.com/image.php?id=164489)
(http://www.audiocircle.com/image.php?id=164490)
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Wow those are coming out great Jim! Nice finish, semi-glossy satin looks just right, imo. And the veneer is beautiful grain and color.
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Some more progress. So finally the mystery piece Lol.
(http://www.audiocircle.com/image.php?id=165202)
(http://www.audiocircle.com/image.php?id=165203)
(http://www.audiocircle.com/image.php?id=165204)
(http://www.audiocircle.com/image.php?id=165205)
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Cabinets coming along too. Next I have to add fabric to grill and install NoRez.
(http://www.audiocircle.com/image.php?id=165207)
(http://www.audiocircle.com/image.php?id=165208)
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Nicely done Jim, beautiful veneer, love the detail on the amp boxes. :thumb:
Best,
Ed
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Thanks, the detail is functional as well. provides venting for cooling. Not sure it needs it but figured it was unique.
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Very nice indeed.
Love these build threads. :thumb:
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(http://www.audiocircle.com/image.php?id=165904)
(http://www.audiocircle.com/image.php?id=165905)
So these are the fronts. Banded in solid cherry. Sides are also cut I just have to band them as well.
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It's has been a while since I last posted. I did a 8 day vacation which knocked out 2 weekends of progress but I am back at it.
(http://www.audiocircle.com/image.php?id=167042)
Uppers after applying finish
(http://www.audiocircle.com/image.php?id=167045)
An assembled upper w/o drivers
(http://www.audiocircle.com/image.php?id=167044)
Time to bring in and start working on a finished assembly
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You are saying you didn't use your 8 day vacation to work on these speakers. What were you thinking? :lol:
Your work looks outstanding - please keep posting great pictures like these. Thanks.
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Hmmm, I just noticed that my lower woofer faces me and the upper is facing away from me. That is the opposite of the standard configuration. My XO is about 225hz. will this be an issue?
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Hmmm, I just noticed that my lower woofer faces me and the upper is facing away from me. That is the opposite of the standard configuration. My XO is about 225hz. will this be an issue?
As long as you have them wired out of phase you will be fine.
Here's a thread Jay posted about this with wiring diagrams
http://www.audiocircle.com/index.php?topic=149708.msg1618744#msg1618744
Mike
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wired correctly yes (opposite phase). and the servos are connected in series. Thanks.
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The servos are wired in series but they have to be wired out of phase also.
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The servos are wired in series but they have to be wired out of phase also.
OK I'll pay special attention to that. Thank you for pointing that out Mike. Theres a good possibility the SC is not wired correctly. I haven't connected them to amps or used them yet.
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The output of the subs may be low when you first get them going. They need to break in a bit before they reach their full output. So be careful with your levels for the first hour or two.
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yep, caution!!
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The servos are wired in series but they have to be wired out of phase also.
Good on the wiring I had it right. The only difference is if you physically place mine upside down Lol!
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Sounds like you've got it all worked out but figured I'd say this anyway....
to keep it as simple as possible I'd come in with the drive leads and connect them in phase to the lower woofer driver coil. then parallel off those and connect to the upper (reversed) woofer driver coil out of phase.
Then take the positive servo lead from the amp and conect to the lower woofers servo coil + terminal. Take the negative servo lead from the amp and connect it to the upper woofers servo coil + terminal. Connect the lower and upper - servo terminals together.
Obviouisly other ways to do it but this would be the easiest
jay
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Thats exactly what I have :thumb:
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I turned on the a370peq amps and they had a loud oscillation. I immediately unplugged them. I wanted to disconnect the servo wires as a test. Can I do this without harming anything? trying to isolate the problem. thanks.
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more progress this weekend. Grills are done, the wiring done bu getting a loud buzz from the speakers. very confusing because I checked the wiring and it seems right.
(http://www.audiocircle.com/image.php?id=167282)
Grill complete, top ready to accept drivers
(http://www.audiocircle.com/image.php?id=167283)
Base and XO board completed. Ready to start populating
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We have lift off. It was wiring. Strangely enough I wired it according to a diagram provided in this forum. Go figure. I rewired it my way and i works. Duh :scratch:
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We have lift off. It was wiring. Strangely enough I wired it according to a diagram provided in this forum. Go figure. I rewired it my way and i works. Duh :scratch:
Send me a link to what you were looking at and let me have a look at it. If there is a diagram out there that is not right then I'd really like to correct it.
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We have lift off. It was wiring. Strangely enough I wired it according to a diagram provided in this forum. Go figure. I rewired it my way and i works. Duh :scratch:
If you wired them using one of the diagrams I provided in the wiring thread, (http://www.audiocircle.com/index.php?topic=149708.0) they will work (your drivers were the opposite of "normal" so of course you'd have to make the necessary polarity adjustments). You noted you had them wired exactly as I posted above (reply 41), that description is correct. As we talked about yesterday, if you ended up with a loud "buzz", you likely had the circuits crossed in the connectors
glad to hear they are now working :thumb:
jay
jay
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Yea, the circuits weren't crossed. It was the polarity on the servo circuits. Now to break them in. Thank you very much for your help Jay. I can't wait to get the toppers operational.
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General question for those that have built H Frames. I was planning on placing my toppers on the H frames. However I noticed there is a lot of vibration from the cabinet. Should I look at alternative means on placement? (Like stands for the toppers?)
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I use Herbie's Fat Dots between mine
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Yeah, those woofers really load those cabients even though they are open Did you line your cabinets with no-rez ? Until I really crank up the SPL, I can place a looney on it's edge on top of an h-frame and it will sit like that until it's pretty loud.
I don't remember how thick you made the top plates but I've found that using 1" as opposed to 1.25" - 1.5" makes them a bit more suseptible to vibration, the no rez does help.
I'm using some Sorbathane under a pair of MTM's right now, may give the Herbie's fat dots a try at some point
jay
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Still have to cut/install NoRez. Also my top plates are 1 inch.
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Updates this Labor Day Weekend!!
(http://www.audiocircle.com/image.php?id=167888)
This is Rev 0 XO installed. I generally dont install the good stuff until values are finalized
(http://www.audiocircle.com/image.php?id=167889)
I was inspired by MLundy and the way he beveled the NoRez so I did it as well. I believe it adds a nice touch.
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Nice, they look great :beer:
Thank Peter for the beveling idea
jay
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Nice, they look great :beer:
Thank Peter for the beveling idea
jay
+1 I copied Peter :thumb:
Mike
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+1 I copied Peter :thumb:
Mike
I'm really mad at Peter because he didn't come up with the idea until AFTER I installed my no res in my Super V's :evil:
Just kidding Peter, it really IS a nice touch :thumb:
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Ok so I fired the babies up and did a bit of listening and measuring. Tweeter is padded a bit too much, easy fix but the harder issue is I have a dip in the Fr at about 170 hz. So here is my set up
ModWright LS100 preamp main outputs have a cap installed to limit bass (approx 80 hz). This goes to my KWA 100SE No active crossover for the top.
Second pair of output (full output) from the preamp goes to the Rythmik A370 bass amp.
I measured the midrange only w/o xo and it goes nicely down to its designed cutoff at 200hz.
I measured the H Frame woofers and I cant get them to go any higher than 150. Hence the gap.
Danny previously mentioned that the woofers-amp combo go up to about 300 hz so I figured I was good. What am I doing wrong?
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You may need to work with the phase control to get them to sum at the crossover point and create a flat response.
Make sure the amp controls for the low pass are in the EXT/12 position.
You can also work with the gain control to increase overall output (thus increasing the crossover point) and see where that gets you.
Be sure you are measuring only one side at a time. If you try to measure both channels at the same time then you will get a cancellation and peak somewhere.
Try different measuring distances to see if it room related.
If you can post the measurements of the woofers, the upper, and the sum of the two.
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A370 set to AVR/EXT (12db/oct) slope ? Maybe a bit of room null ?
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You may need to work with the phase control to get them to sum at the crossover point and create a flat response.
Make sure the amp controls for the low pass are in the EXT/12 position.
You can also work with the gain control to increase overall output (thus increasing the crossover point) and see where that gets you.
Be sure you are measuring only one side at a time. If you try to measure both channels at the same time then you will get a cancellation and peak somewhere.
Try different measuring distances to see if it room related.
If you can post the measurements of the woofers, the upper, and the sum of the two.
Danny,
I will try the phase control again, but I believe I tried that and it didnt help much. I omly have one speaker on at a time. Confirmed I am in the AVR position. As far as the gain, if I bring it up then it will be too loud compared to the toppers. But I will give it a go. I was measuring at about 1 meter from the baffle. I'll measure from the listening position. But I did want to confirm that the amp does not go much higher than 150 hz, correct?
(http://www.audiocircle.com/image.php?id=167938)
mid only
(http://www.audiocircle.com/image.php?id=167940)
woofer only
I'll try to get the sum of the two so you can see.
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Just to confirm the obvious Jim, your Rythmik A370 plate amps are the OB/Dipole version, with the shelving circuit built in?
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Damn, I hope so I bought them from Danny for the H Frames and bought them together with the woofers. How would I tell by looking at them??
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I was measuring at about 1 meter from the baffle.
Ah, there's your problem. 1 meter away is too close for measuring below 200Hz. You'll have to back off to the listening position for ranges below 200Hz.
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OK ill back up to about 8-10 ft. Danny, I sent you an email. I was able to wire up the servo 2 ways and it seems to work either way but something tells me only one way is correct. you'll see in the diagrams i sent. Thanks.
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So Ive been doing some listening and measuring. I have tweaked the crossover as the proper values are quite a bit different from the theoretical or the ones recommended using the software modelling program.
Question: How far from the wall is the recommended spacing? Thanks.
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So Ive been doing some listening and measuring. I have tweaked the crossover as the proper values are quite a bit different from the theoretical or the ones recommended using the software modelling program.
Question: How far from the wall is the recommended spacing? Thanks.
Typically the crossover modeling software is a shot in the dark. Rarely are they close especially if using electrical parameters.
You will need to have any open baffle speaker pulled out at least 3 feet or more from the front wall.
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OK so I am working on the XO and very interesting, I am using a 2 way 12db/oct and the system measures better with both drivers in phase! OK so what could I be doing wrong.
(http://www.audiocircle.com/image.php?id=168151)
The other issue is a crappy looking impulse (tweeter only)
(http://www.audiocircle.com/image.php?id=168152)
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I take it that is your upper section?
First of all I can tell by the impulse response that you are way too close. Back off to 39". Then set the start time on the impulse response to about 2.75ms and stop it at 6.75ms. That will give you a good clean time window of 4ms without room related reflections. And be sure that the speaker is not sitting close to a side wall for the measurement. And start off with the response on the tweeter axis.
When looking at a 1 meter gated time window you can crop everything below 200Hz because you really won't be measuring or catching anything below that.
And with that type of crossover they may very well measure better with both drivers in phase.
Shoot the mid individually and tweeter individually then overlay the response of the two together. That will tell you more.
And to see how well they are in phase, be sure to check vertical off axis responses. I stay with the 1 watt/1 meter reference and than move the mic up 4" per measurement.
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I use OmniMic V2 so I will have to see if I can set start-end on gating. I know i can set end but not sure if I can gate the start.
Interesting, I did some more measurements of the Tops and the measured dipole peak and the results of a sim using Edge came out almost exactly the same. I like when that happens (as you can tell I am a newbie :) )
So I have the first dipole peak at about 450/500 hz I need to tamp down about 6 db. I used an online calculator for a RLC notch. got my values 68uf,8 ohm, 1.5mh. Havent tried it yet but I assume this get installed after the XO in series with the Mid. Anyone have experience/luck with this?
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I use OmniMic V2 so I will have to see if I can set start-end on gating. I know i can set end but not sure if I can gate the start.
Interesting, I did some more measurements of the Tops and the measured dipole peak and the results of a sim using Edge came out almost exactly the same. I like when that happens (as you can tell I am a newbie :) )
So I have the first dipole peak at about 450/500 hz I need to tamp down about 6 db. I used an online calculator for a RLC notch. got my values 68uf,8 ohm, 1.5mh. Havent tried it yet but I assume this get installed after the XO in series with the Mid. Anyone have experience/luck with this?
You can adjust or shift the peak with the lengths of the side wings. This is why I do so much measuring and testing of the side wing lengths. Ideally you can create a flat response with no need for notch filters.
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Danny, I modeled it to shift the peak, but keep in mind the trade off is I also raise my cutoff frequency so it doesn't meet the woofers. Thats why the higher cutoff frequency for the woofer was critical in this particular application. Unless I go with a larger driver but then its more cabinet work :duh:.
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A longer side wing should shift the peak further down and help them reach the lower woofers.
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OK so rather than mess with my current physical build and XO i decided to insert my minidsp into the line and play with that. Settings are as follows:150hz +2db Q=1.6 (This improves integration with the H Frame)
450hz -3db Q=2.8 (removes peakiness in the Mid) Sounds better.
(http://www.audiocircle.com/image.php?id=168417)
Ignore hump in the low bass around 25hz. I fixed it, Ill post a new Fr.
Now I will spend some time listening to it and fine tuning. I am not used to leaving the minidsp in the loop so I don't know how "pure" sounding it is. But it does smooth out the Fr. Thanks ALL
EDIT: Forgot to mention XO HP is 90hz for the toppers 24db/oct
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Now I will spend some time listening to it and fine tuning. I am not used to leaving the minidsp in the loop so I don't know how "pure" sounding it is. But it does smooth out the Fr. Thanks ALL
My experience is that it will suck a lot of the life out of the music. The sound stage will flatten out. Depth goes away. Detail is lost. And it can be a bit harsh.
If you can take care of the response issue passively and use a good quality DAC instead then things should improve significantly.
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Danny, my expectations match your findings, I will need to spend more time listening to it. My other equipment is more than decent (at least in my eyes) Modwright electronics, VPI Classic 2 table, MicroBenz cart, Burson Conductor Dac, Wywires, Emotiva transport, etc.
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Ok so after some investigation and analysis Brian Ding acknowledges that the the amp limit on the top end is about 150 hz. My toppers go down to 200 hz. But he thinks that the major culprit is a cancellation in the room. He does believe that I may be able to "smooth" it out somewhat by experimenting with room placement. Currently I am 3 1/2 ft from the front wall and 6 ft from the side wall. I remember reading where it said to start close to the front wall and move forward in 2 inch increments until I get the best spot. Any thoughts on this?
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Ok so after some investigation and analysis Brian Ding acknowledges that the the amp limit on the top end is about 150 hz. My toppers go down to 200 hz. But he thinks that the major culprit is a cancellation in the room. He does believe that I may be able to "smooth" it out somewhat by experimenting with room placement. Currently I am 3 1/2 ft from the front wall and 6 ft from the side wall. I remember reading where it said to start close to the front wall and move forward in 2 inch increments until I get the best spot. Any thoughts on this?
You are describing something like the Sumiko Master Set Method
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Ok so after some investigation and analysis Brian Ding acknowledges that the the amp limit on the top end is about 150 hz. My toppers go down to 200 hz. But he thinks that the major culprit is a cancellation in the room. He does believe that I may be able to "smooth" it out somewhat by experimenting with room placement. Currently I am 3 1/2 ft from the front wall and 6 ft from the side wall. I remember reading where it said to start close to the front wall and move forward in 2 inch increments until I get the best spot. Any thoughts on this?
In the open baffle configuration these are supposed to play up to 300Hz. I just checked out my H-Frames. I didn't turn on the power amp to the top sections so only the H-Frames were playing. I used discrete sine wave tones from 20Hz to 400Hz. The tone files I have include 100Hz, 250Hz and 400Hz (nothing in between). With the crossover turned all the way up (pointing at 150Hz), output was solid at the listening position to and including 250Hz. While audible, 400Hz was significantly diminished.
As long as your amps have the servo control board with the OB circuit for the SW-12-16FR drivers and everything is wired correctly I'm not sure why you are not getting this type of output.
Unless you are using a version of the A370 amp that has both "Line In" and "LFE In" RCA jacks (A370-PEQ3, -XLR 2 or -XLR 3) and you have the RCA interconnects plugged into the "LFE In" jacks. When this happens the crossover control knob is by-passed. The "LFE In" jacks assume you are setting the crossover points in a home theater receiver.
If you are using the A370PEQ version of the amp this is not an issue because it does not have any "LFE In" inputs.
One way I was told to troubleshoot if it is a speaker issue or a room interaction issue is to stick your ear right up to the opening (or even a little inside the opening) of one of the drivers and play the tone. If you can hear the tone with your ear right at the opening, so there is no chance for any room interference, but cannot hear it (or it is significantly diminished) at the listening position there is a room issue. If you can't hear it right at the speaker opening it is a speaker issue.
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See response embedded
In the open baffle configuration these are supposed to play up to 300Hz. I just checked out my H-Frames. I didn't turn on the power amp to the top sections so only the H-Frames were playing. I used discrete sine wave tones from 20Hz to 400Hz. The tone files I have include 100Hz, 250Hz and 400Hz (nothing in between). With the crossover turned all the way up (pointing at 150Hz), output was solid at the listening position to and including 250Hz. While audible, 400Hz was significantly diminished. <<I will try this method>>
As long as your amps have the servo control board with the OB circuit for the SW-12-16FR drivers and everything is wired correctly I'm not sure why you are not getting this type of output.
Unless you are using a version of the A370 amp that has both "Line In" and "LFE In" RCA jacks <<No>> (A370-PEQ3, -XLR 2 or -XLR 3) and you have the RCA interconnects plugged into the "LFE In" jacks. When this happens the crossover control knob is by-passed. The "LFE In" jacks assume you are setting the crossover points in a home theater receiver.
If you are using the A370PEQ version of the amp <<Yes>>this is not an issue because it does not have any "LFE In" inputs.
One way I was told to troubleshoot if it is a speaker issue or a room interaction issue is to stick your ear right up to the opening (or even a little inside the opening) of one of the drivers and play the tone. If you can hear the tone with your ear right at the opening, so there is no chance for any room interference, but cannot hear it (or it is significantly diminished) at the listening position there is a room issue. If you can't hear it right at the speaker opening it is a speaker issue.
OK so the reason Brian said it will not (or maybe should not is because of the inductance of the voice coil in the woofers. I will try different methods
(http://www.audiocircle.com/image.php?id=168932)
Note the drop just below 200 hz, Brian says that is room issue. either way you can see it wont make 200 hz
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Jimbones,
What's the trick with the veneer making it wrap around from the top panel to the side panel? I can't seem to zoom in enough to notice if it was mitered or a small edge. If it's a small edge, did you apply the side, flush trim, top, flush trim?
Jim
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See response embedded
OK so the reason Brian said it will not (or maybe should not is because of the inductance of the voice coil in the woofers. I will try different methods
(http://www.audiocircle.com/image.php?id=168932)
Note the drop just below 200 hz, Brian says that is room issue. either way you can see it wont make 200 hz
Try the trick of generating a 200Hz tone with your ear right up next to the speaker and see if you can hear it.
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Jimbones,
What's the trick with the veneer making it wrap around from the top panel to the side panel? I can't seem to zoom in enough to notice if it was mitered or a small edge. If it's a small edge, did you apply the side, flush trim, top, flush trim?
Jim
Ha ha it's no trick. What i did was use solid cherry on the ends and router them. Came out looking very similar to Tineo.
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Keep in mind that your crossing over point will be where they are -6db down. If you are at an average of 76 then your -6db down point is 65db. You're still hitting 65db all the way up to about 280Hz. So playing up there isn't the problem. You just have a room related dip at around 180 to 190Hz.
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I am playing with spk placement. Still see dip. Grrrr. Time to get agressive. :banghead: :banghead:
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I am playing with spk placement. Still see dip. Grrrr. Time to get agressive. :banghead: :banghead:
You haven't mentioned which side you are having the issue with either. Is it the left side or the right side? Post measurements of each and we can start to narrow it down.
I take it that you are now measuring at the listening position?
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OK so I think I eliminated the 10db narrow dip at 180hz. I pushed the speakers within 2 ft of the front wall, they were pushed about 2 ft closer (didnt measure but probably 8 ft center to center) I had a peak at 45hz which I was able to knock down using the Eq adjustment. The mic is now at the listening position. I moved the bass traps around but seem to have too much affect. see response below.
(http://www.audiocircle.com/image.php?id=168989)
So would anybody say my work is done with this (left) woofer? Should I do the right now, and then in combo?
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That looks pretty good.
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I have finally get these babies set up right now. The sub barely goes up high enough but it works. I changed the caps in the XO to Jantzen Silvers. Wow these speakers are really singing. i would classify the sound as relaxed and musical. Not super duper detail (as in overdone), but enough detail where its needed. I listed to another pair of speakers recently that had uber amounts of detail and it was fatiguing.
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I have finally get these babies set up right now. The sub barely goes up high enough but it works. I changed the caps in the XO to Jantzen Silvers. Wow these speakers are really singing. i would classify the sound as relaxed and musical. Not super duper detail (as in overdone), but enough detail where its needed. I listed to another pair of speakers recently that had uber amounts of detail and it was fatiguing.
That sounds great.
I hate fatiguing speakers myself. I love good detail levels though. Just not in a way that makes them bright or elevates the top end.
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I was afraid that little woofer you picked wasn't going to like the open baffle. I knew it would be a stretch even with the asymmetrical side wings to get it to play down low enough while a filter kept it from playing too low and getting beat up.
I'm glad it worked out, and glad I was able to help.
Next I need to talk you into getting all of those connectors off of the crossover and upgrade some of those parts that are holding it back. Some tube connectors would be a nice upgrade too.
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The coils are all foil and the caps are silver! You mean better than that!! :o :o
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The coils are all foil and the caps are silver! You mean better than that!! :o :o
(http://www.audiocircle.com/image.php?id=167888)
It looked like Jansen (recycled Copper) inductors. Maybe I am mistaken. Looks like Electrolytic caps as a high pass filter. And lots of plastic and possibly steal connectors in the path. I think those typical have hold down screws that are ferromagnetic.
It looks like Cardas Copper binding posts. I like those too. I even stock them, but they are a level down from the tube connectors.
Maybe that is not the final crossover?
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Ok yea thats an older pic. I will post newer pics. I understand the terminal strip, that was done to facilitate changes to the XO.
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Ok yea thats an older pic. I will post newer pics. I understand the terminal strip, that was done to facilitate changes to the XO.
Gotcha. When I am designing a crossover and taking measured responses I use a pile of wires that I have with alligator clips on the ends so that parts can be dropped in and out of the circuit quickly and easily.
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I hear ya. I'm clumsy. I would short out 2 clips (unintended) and blow my amp up so I try to be as neat as possible. In the past I have blown up hi power amps. I remember blowing a 30 amp circuit breaker when I shorted the outputs on my Acoustat TNT 200. It actually welded the banana plugs together.
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I hear ya. I'm clumsy. I would short out 2 clips (unintended) and blow my amp up so I try to be as neat as possible. In the past I have blown up hi power amps. I remember blowing a 30 amp circuit breaker when I shorted the outputs on my Acoustat TNT 200. It actually welded the banana plugs together.
My test amp shuts off if shorted. If not I would have fried half a dozen of them over the last 20 years.
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(http://www.audiocircle.com/image.php?id=169738)
Hopefully this looks better.
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Okay, I am still puzzled by that. You have some good parts in there, but the signal is still passing through connectors that are likely held down with steel screws. I see one good quality Mills resistor, one inexpensive but decent Lynk resistor and one really bad sand cast resistor. All of which are in the signal path (including the ones in shunt). Wire looks mixed too and might even be Silver coated Copper. You have nullified some of the good quality parts with some bad, plus connectors.
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OK so the green are Mundorf resistors. No good? Also I was told that shunt resistors are not critical. I have them in Mills and can change. There are some silver coated copper as well as some good copper (I forget if it was OHNO but something reasonably good like that.
I agree with the connectors as I have said it allows me to quickly remove/install to make changes to the XO. I could just eliminate them and solder directly.
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OK so the green are Mundorf resistors. No good? Also I was told that shunt resistors are not critical. I have them in Mills and can change. There are some silver coated copper as well as some good copper (I forget if it was OHNO but something reasonably good like that.
I agree with the connectors as I have said it allows me to quickly remove/install to make changes to the XO. I could just eliminate them and solder directly.
Still the Mills is the higher quality resistor, and the shunt resistors are still in the path just like the shunt inductor.
Silver coated Copper causes an audible phase shift in the upper frequency range that is pretty easy to hear in some cases. I tend to avoid it.
Also if you can minimize any break in the wire as it goes from binding posts to components to drivers, then that will help too.
And I understand the connectors allowing you to easily swap parts. Nothing wrong with that. But when you finalize it all then I'd rewire it all with good wire and no connectors.
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I have had some listening sessions with friends and they are hearing the dip in Fr at about 175hz between woofers and mid. So I figure that I make the baffle bigger for the mid and take a measurement. No difference then I decide to try to enclose the mid by creating a top and back and extend the sides. So it is a lossy enclosure but I figure I am impeding he rear wave. No dice measurement changes minimally. What am I missing. It shouldnt be that hard to get a mid to go down to 150hz is it?
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I have had some listening sessions with friends and they are hearing the dip in Fr at about 175hz between woofers and mid. So I figure that I make the baffle bigger for the mid and take a measurement. No difference then I decide to try to enclose the mid by creating a top and back and extend the sides. So it is a lossy enclosure but I figure I am impeding he rear wave. No dice measurement changes minimally. What am I missing. It shouldnt be that hard to get a mid to go down to 150hz is it?
I think I warned you in the beginning that mid was not a good candidate for open baffle. The Qts was a bit low. It could be made to work though.
I would add surface reflections around the drivers. Just increase the wing length to extend the range a little lower. However, extending the range a little lower might me a reduced output too.
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Yes you did. However we discussed sound "quality" as opposed to output. As I understand it the lower cutoff frequency of the mid in an open baffle is a function of its Fs and baffle wing dimension. In order to get down to 150hz the baffle needs to be about 30 inch so i put on temporary wings 14 in each side plus the with is 9 inch. No change. Do I need to go to an 8 inch driver? I don't think that will help based on what I see.
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Yes you did. However we discussed sound "quality" as opposed to output. As I understand it the lower cutoff frequency of the mid in an open baffle is a function of its Fs and baffle wing dimension. In order to get down to 150hz the baffle needs to be about 30 inch so i put on temporary wings 14 in each side plus the with is 9 inch. No change. Do I need to go to an 8 inch driver? I don't think that will help based on what I see.
If you enclose it on both sides then the upper frequency ranges that it covers will propagate within that space and set up a cavity resonance. You have to keep it open and asymmetrical to avoid the cavity resonance issue.
You could mount four of our M-165 woofers below that mid in a series parallel arrangement to cover from 200Hz down to around 80Hz. Basically build it like the NX-Otica but with your upper section. Then it will easily blend to the servo subs.
See pics of the cabinet: http://www.audiocircle.com/index.php?topic=141654.msg1510858#msg1510858
http://www.audiocircle.com/index.php?topic=143221.msg1528962#msg1528962
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Yea, my question was more fundamental, as I want to learn what governs low cutoff frequency> As I see it Qts, Fs and Baffle dimensions. Technically there is no reason why the Mid I have cant reach 150hz. Now it may not "sound good" but I should get down to 150 hz, no??
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Yea, my question was more fundamental, as I want to learn what governs low cutoff frequency> As I see it Qts, Fs and Baffle dimensions. Technically there is no reason why the Mid I have cant reach 150hz. Now it may not "sound good" but I should get down to 150 hz, no??
Yes, those are the factors to look at. With that woofer the compliance or Qts is low and it needs the loading of an air space (inside a box) to bring the total Q up to an nominal .7 Qtc level. And in an open baffle configuration it is just not there.