AudioCircle

Industry Circles => GR Research => Topic started by: flavo on 12 Jan 2018, 01:09 am

Title: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 12 Jan 2018, 01:09 am
Hi all. I'm about to hit the go key on an Otica MTM and a double H-frame build.
The easy part of my questions will be about the build. I'm a little smitten with the way ebag4's build came out and plan on emulating (hopefully not too poorly)  to a certain extent his build.  I have seen specific dimensions for the H-frames but not the Otica MTM so I'm not sure how they fit together. Going off of random photos I can get off of the interwebs though. It appears they have different depths.
I plan on buying the flat pack for the MTM and building my own H-frame

The flat pack appears to be hanging off of the back of the H-frame.

Assuming this is the case, That would mean either the the MTM was cut down or the H-frame was added to in depth, and also height as the woofers are both facing forward.
Is adding to the depth an issue or should the mtm be cut down?

Also it appears that ebag4 added a 1/2" thickness to the h-frame for his speaker grills. Was this also accounted for and the h-frames are a total of 1" wider now?

(http://www.audiocircle.com/image.php?id=174347)


(http://www.audiocircle.com/image.php?id=174348)


Next big questions are about my room and system.
Luckily I am only 5'8". The ceiling height in this space is only 6'4" is in the highest spot. Am I going to have unwanted issues putting these speakers in here?

And the system. Keithh mentioned his passive being an issue in this chain.
I'm not very knowledgeable about what will and wont work. I'm putting together a better system then I had and I just want everything to work. I currently have a 3.5 watt 2a3 mono block amp.
http://www.triodelab.com/2a3-set-mono-b-locks/
and plan on adding a LDR  passive pre. Either a Tortuga or Truth. Do you foresee any issues with this? Maybe I should start a separate thread else where on building my components  other then the speakers?

I really appreciate the help and look forward to your feedback.
Mike


(http://www.audiocircle.com/image.php?id=174351)


(http://www.audiocircle.com/image.php?id=174354)




Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: 2bigears on 12 Jan 2018, 02:52 am
 :D nice build .   Those should sound unreal.  Would love to hear those indeed. 
       Your room looks good for sound. A few panels and corner treatments ,  whoa !!
     :D
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Captainhemo on 12 Jan 2018, 03:04 am
Hey Mike
If you  use a top  plate on the  H-frames  like our  overhanging  ones (17:" deep),  the  base we ship with the  MTM flat packs will be almost  flush,, it shouldn't overhang at all.   
LMK if you  are  going to want some MTm's  as I'm doing some  cutting  within the next  couple weeks., might still be able to get some of those inthe   "q"   

Danny can advise yo u better  on   the height of the room....  I think  you'd ideallly want   some additonal  height but not sure it  will be a  deal breaker. Adding  some diffusion on your  ceiling myay  be a big help....
How big is the room aside from the height ?  The other  thing is  that  3.5  watts  is not  a  ton of power witha  93 - 93.5 db speaker... at what  SPL's do you  tend to   listen  to  your  tunes at ?

jay
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Danny Richie on 12 Jan 2018, 03:30 am
The good thing about an open baffle design is that the response will cancel at 90 degrees off axis and minimize some of the room interactions. This is also true in the upward plane. So they should work as well or better than a typical design in that regard.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 12 Jan 2018, 04:48 pm
Hey Mike
If you  use a top  plate on the  H-frames  like our  overhanging  ones (17:" deep),  the  base we ship with the  MTM flat packs will be almost  flush,, it shouldn't overhang at all.   
LMK if you  are  going to want some MTm's  as I'm doing some  cutting  within the next  couple weeks., might still be able to get some of those inthe   "q"   

Danny can advise yo u better  on   the height of the room....  I think  you'd ideallly want   some additonal  height but not sure it  will be a  deal breaker. Adding  some diffusion on your  ceiling myay  be a big help....
How big is the room aside from the height ?  The other  thing is  that  3.5  watts  is not  a  ton of power witha  93 - 93.5 db speaker... at what  SPL's do you  tend to   listen  to  your  tunes at ?

jay

Pretty please get me an MTM cut for the Otica!

I can't speak on SPLs as I wouldn't know how to state it.  However, I don't typically listen all that loud but sometimes do. So I guess we'll see how they perform. I was about to order a chip amp board anyway that will have plenty of power. I can play with that and see what I think.

The room is 12x25 I think, with the other 1/2 of the room used as my office.  I've got to check again. Am very willing to play with room treatments.

I plan on building the h-frame  with no overhang. Much like the way Ebag4 did.
I'm sure he or Danny will see this thread before long and can likely answer.  But I'm trying to find out if the h-frame should get stretched to meet these measurements. Depth wise to meet the 17" long mtm base and width wise as Ed appears to have made his sides and tops 1.5" plus an additional .5" for the speaker frame stops.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 12 Jan 2018, 05:06 pm
I just sent an email to Keith to see if he could be of any help on the passive preamp problem.
I was hoping to go Passive with this set up as well.
What is the recommended hook up path for these?

Source>dac>pre>amp and then RCA splitter or run to the 370s with high level/speaker cable?
If it matters, I plan on putting together 3255 chip amp. It is configured for 8ohm.
http://www.audiocircle.com/index.php?topic=152869.0
Thanks everyone.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Danny Richie on 12 Jan 2018, 05:38 pm
I just measured the whole length of the long wing on my NX-Otica and only get 15.5". That's not front to back length. That length would be a little shorter.

The depth of the standard H frame is 14". So increasing it a little over a half of an inch each direction is not a problem.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Captainhemo on 12 Jan 2018, 06:49 pm
I just measured the whole length of the long wing on my NX-Otica and only get 15.5". That's not front to back length. That length would be a little shorter.

The depth of the standard H frame is 14". So increasing it a little over a half of an inch each direction is not a problem.

Well, the Otica MTM base is  aprox  16.25" so  you'd need to  extend the  cabinet  just over an  inch  each way in terms of depth

If you  are veneering  the h-frmes  the flush nouints will be no issue... if you are planning on painting, prepare for   some serious work to deal wiith that  seam  down each side  and   around the front  / rear corners.  They are not fun to deal.  This  piano black pair took a ton of work and  numerous coats of epoxy/block sanding

(http://www.audiocircle.com/image.php?id=157964)

Even if you veneer, do a  good job on those seams  and then seal them up  with something.
the seams   are primarily why  we  try and get  guys to  go with the overhainging tops, they turn that seam into a transition and  "you" never have to worry about them

jay
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: ebag4 on 12 Jan 2018, 09:45 pm
Hi all. I'm about to hit the go key on an Otica MTM and a double H-frame build.
The easy part of my questions will be about the build. I'm a little smitten with the way ebag4's build came out and plan on emulating (hopefully not too poorly)  to a certain extent his build.  I have seen specific dimensions for the H-frames but not the Otica MTM so I'm not sure how they fit together. Going off of random photos I can get off of the interwebs though. It appears they have different depths.
I plan on buying the flat pack for the MTM and building my own H-frame

The flat pack appears to be hanging off of the back of the H-frame.

Assuming this is the case, That would mean either the the MTM was cut down or the H-frame was added to in depth, and also height as the woofers are both facing forward.
Is adding to the depth an issue or should the mtm be cut down?

Also it appears that ebag4 added a 1/2" thickness to the h-frame for his speaker grills. Was this also accounted for and the h-frames are a total of 1" wider now?

Hi Mike, here's what I did.  The kit I got from Jay was one of his beta layouts, it came with the wings and baffle, no base.  The large wing is 15", I built the base to reflect the footprint of the baffle and large wing so my top half is 15 3/4" deep.  I made the H frame a little deeper than normal, Danny told me that the deeper the front and rear sections, the lower the top frequency the sub can reproduce, this has not been an issue with the Otica.  The overall depth of my sub is 15 3/4" so I added about an inch in each direction.

With regard to the grills, they are actually built on a 3/4" frame, they are inset to the H frame 3/8" and protrude the front by 3/8".  This allowed me to rabbet out the top of the grill so it could overlap the middle section and match up to the 3/8" overlap of the MTM.

Hope that helps!

Best of luck with the build!
Ed
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 12 Jan 2018, 10:17 pm

If you  are veneering  the h-frmes  the flush nouints will be no issue... if you are planning on painting, prepare for   some serious work to deal wiith that  seam  down each side  and   around the front  / rear corners.  They are not fun to deal.  This  piano black pair took a ton of work and  numerous coats of epoxy/block sanding


I definitely have more experience with veneer then I do painting. I worked in a cabinet shop for quite a while so it all seems simple in my head. But the more I think of it, I realize I don't have a spray booth or the Catalyst system to go with it that the guys there were using.
If I did paint i'd be going with a matte finish which would help a bunch I'm sure. You've certainly got me a bit scared (educated) but not really deterred. haha. Worst case, I veneer. I like a wood too.

Hi Mike, here's what I did.  The kit I got from Jay was one of his beta layouts, it came with the wings and baffle, no base.  The large wing is 15", I built the base to reflect the footprint of the baffle and large wing so my top half is 15 3/4" deep.

With regard to the grills, they are actually built on a 3/4" frame, they are inset to the H frame 3/8" and protrude the front by 3/8".  This allowed me to rabbet out the top of the grill so it could overlap the middle section and match up to the 3/8" overlap of the MTM.

Wonderful. It's a beautiful build you did and I'm still trying to figure out that bottom portion of the MTM you did by hand with multiple angles. Beautiful job.  Thank you Ed
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: mlundy57 on 13 Jan 2018, 05:21 am
Mike,

The best thing I've found for sealing and taming MDF seams is West System epoxy (105 Resin and hardener of choice). Two coats. Apply one, sand it back, apply the second then sand that one back also. Finally scuff sand with 100 grit before applying the veneer.

Mike
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Captainhemo on 13 Jan 2018, 05:46 pm
Mike (flavo),    wasn't meant to scare you  !!  Just  wanted  to let you  know to be prepared to deal with  the seams involved with flush   tops.

jay
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 13 Jan 2018, 07:37 pm
Mike,

The best thing I've found for sealing and taming MDF seams is West System epoxy (105 Resin and hardener of choice). Two coats. Apply one, sand it back, apply the second then sand that one back also. Finally scuff sand with 100 grit before applying the veneer.

Mike

Excellent advice, thank you. I'll likely pick some up.
Would the process be different or more difficult if I was going to a low gloss or matte paint?
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 13 Jan 2018, 07:40 pm
Mike (flavo),    wasn't meant to scare you  !!  Just  wanted  to let you  know to be prepared to deal with  the seams involved with flush   tops.

jay

Not at all Jay. I want to be educated going into this and appreciated the advice. The more I think about it, the more likely I am to go with veneer just for the look alone. And if paint is a PITB. That just makes the decision that much easier.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: mlundy57 on 13 Jan 2018, 09:34 pm
Excellent advice, thank you. I'll likely pick some up.
Would the process be different or more difficult if I was going to a low gloss or matte paint?

No different regardless of how you finish them. The idea is to seal and stabilize the seams so they don’t show throught the finish down the road

Mike
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: gregfisk on 14 Jan 2018, 07:22 am
No different regardless of how you finish them. The idea is to seal and stabilize the seams so they don’t show throught the finish down the road

Mike

Mike, do you use the fast hardener or the slow? And, what kind of shelf life does this have?

Thanks
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: mlundy57 on 14 Jan 2018, 06:15 pm
Mike, do you use the fast hardener or the slow? And, what kind of shelf life does this have?

Thanks

Greg,

I have used the slow hardener but the fast would work also. I'll most likely use the fast on the Skinny 6s and Flat 5 I'm building because the slow pretty much has to sit overnight before sanding it back. Larry (lacro) has a lot more experience with the West epoxy than I do. Maybe he'll chime in.

Shelf life is basically indefinite as long as you keep the metering pumps on the cans. The metering pumps are calibrated to give the right ratio so one pump of hardener to one pump of resin. Couldn't be easier.

Mike
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Captainhemo on 15 Jan 2018, 06:41 pm
IIIRC,  the fast  hardner is also  non-blushing.   If you are not using a non blushing hardner, you have to be sure to sand off the  hazy (blushed)  surface before applying anything else to   previous coats.
As Mike mentions,  Larry is a  wealth  of info on this subject  :thumb:

We've been using a penetrating epoxy here as well,   it soaks into the mdf more and  really toughens it up. Once  a layer or two are applied it will begin to build,  or you  could switch to  the reg  (thicker)  epoxy.  I believe Larry  told me you could also  just thin your reg epoxy with pure alcohol to  effectivly make it a penetrating epoxy. sure if he chimes in , he'll comment more on this

this  has ben working well for us
 
 Oh, and  pay attention to the ratio's, not every hardner uses the same 1:1 ratio, pay attention if you are buying  a pump or using a  measuring beaker  etc


jay
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: mlundy57 on 15 Jan 2018, 08:01 pm
Oh, and  pay attention to the ratio's, not every hardner uses the same 1:1 ratio, pay attention if you are buying  a pump or using a  measuring beaker  etc

jay

Good point. The West uses a 2:1 ratio. The pumps are metered so that one pump each of resin and hardener provides the proper ratio. You don't have to buy the pumps ($25 at West Marine for a set) but they sure make life easier.

Mike
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: gregfisk on 16 Jan 2018, 06:54 am
Thanks guys, this is a problem I've had for years with MDF and not just on speakers. There's nothing worse than getting a really good paint job on something and the down the road a crack appears and ruins all of your hard work.

Every time I've had a seam in a project it cracks no matter what I've tried. Very frustrating indeed :duh:.

Greg
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: lacro on 16 Jan 2018, 01:52 pm
Seam hiding MDF is a challenge for sure. Epoxy can help hide the seams, but I find the flexible (relatively) epoxies are a better choice. The seasonal temperature/humidity changes that cause the MDF seam print through can be helped with epoxy. Which epoxy you choose can also make a difference. Wests system epoxy is a great product, but it is one of the hardest epoxies, almost brittle. An old wood strip canoe/kayak builders trick was to use System Three epoxy (slightly softer) for initial coats, and use Wests epoxy (very hard) for the final coat. In theory the underlying coats allow for some movement without cracking, and the hard final coat adds abrasion resistance. Speaker cabinets don't flex like a boat, so this is probably not an issue. However, I prefer non blushing flexible epoxies with slow hardeners (longer pot life) for all applications.

On my last speaker build a X-CS Encore center channel, I used thickened epoxy for gluing the panels instead of yellow carpenters glue. Then I coated the cabinet with Raka Epoxy (slow hardener) thinned 5-10% with Lacquer thinner. I waited a day, and scraped off any runs/thick spots with a utility knife blade, and lightly sanded the surface. Then I applied 2 more not thinned coats of epoxy, sanding between coats.

Thinning epoxy is normally not a good idea as it can weaken the epoxy, but for speaker building, it's not a problem. The penetrating ability of the thinned epoxy, especially on edges really stiffens the MDF. The subsequent coats of not thickened  epoxy make for a nice dent resistant hard surface that helps prevent seam print through.

If your going to paint the cabinets, It's best to use some type of transition primer over the epoxy as some coatings have solvents that might attack the epoxy. I just use Zinsser Seal coat (shellac). Also, I wait 5-7 days for epoxy to fully cure before applying anything.

Epoxy has an extremely long shelf life. I have used 15 year old epoxy with no problem. The pumps do make life easier but I don't use them for accurate measuring, just for transferring to mixing cup. I prefer to use a digital gram scale to weight the epoxy/hardener. I can mix very tiny amounts using the scale. Most epoxy suppliers list their mixing ratios by volume and also by weight.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: mlundy57 on 16 Jan 2018, 02:44 pm
Larry,

Which of the Raka resins and hardeners do you prefer?

Mike
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: tosob on 16 Jan 2018, 04:02 pm
Can you veneer over the top of the resin? Would you use wood glue or veneer over the resin and wet it out like you would glass?
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: ebag4 on 16 Jan 2018, 05:37 pm
I'm still trying to figure out that bottom portion of the MTM you did by hand with multiple angles.
Mike (Flavo), this is something that I posted for Mike (MLundy) yesterday, I thought it might help to clarify:

(http://www.audiocircle.com/image.php?id=174596)

It's not completely accurate because the cutout for the MTM base actually has a back portion, but it covers the basic concept.

Best,
Ed
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 17 Jan 2018, 02:49 pm
Ed, I've been following your post quite closely so I saw this when you posted over there. It's very helpful and I'm very appreciative.  :thumb:

There has turned out to be a wealth of knowledge being posted in here. I'm 100% positive that all of it is going to be quite helpful to me and likely many others.

Thanks everyone  :D

With the servo kits:
Wiring from the amp to the speaker. I'm assuming I'll need hook up wire and a connector. Danny offers the Neutrik so I'm assuming that's the best option? When I get that from him, does it come with male and female ends and the female end will get inserted into the H-frame?

The servo subs will be used for both my 2 channel rig and my HT amp. Is there some sort of switcher that is recommended for this process so I don't have to keep switching the plugs out?

The same goes for the MTM with serving double duty. Can I use a switcher of some sort without degrading the signal?

Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Captainhemo on 17 Jan 2018, 05:46 pm
Yeah,   the wire and connectors Danny sells are great. You  do get a male  / female combo.  People do it different ways.  Some put the   female connector inthe cabinet, some put it in the amp box and leave a pig tail  out the back of the sub with  the male conector.  Some even  put a female connector in both the  sub cabinet and the amp box then make a  cable  with  a male connector at each end.
In any event, it's very important to be sure not to cross anything, sometimes   the sub will still  play when wired incorrectly but it won't function properly.  Sometime , depending on  how you mistakenly cross wires,  you'll end up with a   a very loud buzz, and not the kind you want  either   :lol:
I did up some wiring diagrams  and posted in a  wiring  specific thread that may be of use

http://www.audiocircle.com/index.php?topic=149708.msg1600884#msg1600884

If you  are  planning to watch  movies  with long drawn out bass/explosion type scenes, you'd  be better of with a sealed  12"  servo sub for the HT duty.  This really wasn't what the Ob subs were designed  for
As for the switching,  can't help  you  there but I'm sure  some others will  jump in.  Personally, I don't like to add  to  the signal path if I don't have to....  IIRC,  Mike has used both sets of  inputs on the A370, one for 2-ch  system input, one for HT system input , that may work  for you  at least for the subs ?



jay
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: lacro on 17 Jan 2018, 06:00 pm
Larry,

Which of the Raka resins and hardeners do you prefer?

Mike

Mike,
There are lots of good epoxies, and everyone has their favorite. I just settled on Raka after having consistent good results building boats. It has all the attributes I wanted.  I like 127/350 mixed 100 to 44 ratio by weight, 2 to 1 by volume.

Here's the description of the 350 hardener from Raka site. I feel it's a pretty accurate description:


DESCRIPTION OF SPECIAL HARDENER 350 NON BLUSHING

We feel this hardener is second to none in its ability to resist blushing, white clouding and water spotting.   Blushing is the greasy surface film on cured epoxy caused by humidity in the air as the epoxy cures. 

We tried many non blushing type hardeners before we settled on the 350 formulation.  Regardless of the most extreme humidity or cool dropping temperatures our tests show this hardener gives an excellent high gloss and clear, blemish free coatings.  This formulation also has the best resistance to cratering and trapped air bubbles in the cured epoxy coating.

Raka 350 like our other hardeners has good strength properties, excellent water resistance and the best general chemical resistance of our hardeners.  Cured epoxy using the 350 formulation will also give better flexibility to resist impact and wood deformation.   The 350
is mixed by volume one part hardener to two parts of our 127 or 900 H.P. Resins. This system has a good pot life approximately thirty minutes at room temperature yet is relatively quick curing compared to other hardeners and can be used in temperatures down to 60 F  .   The wide temperature use ability of this system will simplify the needs of many customers who do not want to have to carry a combination of fast and slow hardeners.   350 reaches a tack free stage quickly and can be sanded in less than twelve hours at room temperature.   350 is more expensive than our other hardeners but when combined with our economical Resins the average price per gallon is the best competitive value around.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Early B. on 17 Jan 2018, 07:36 pm
The servo subs will be used for both my 2 channel rig and my HT amp.

Nah, don't do that. Get a separate sub for HT.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Danny Richie on 17 Jan 2018, 08:27 pm
Nah, don't do that. Get a separate sub for HT.

The servo subs will work great in both applications.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 17 Jan 2018, 11:32 pm
My understanding is that the h-frames aren't made for HT but more for musicality. My plan was to build the h-frames and I talked myself into building a sand box or similar sub for the rear of the room. Well once I talked myself into that I figured the Otica MTM portion was only another $600 over the sandbox sub. Funny how I can talk myself into this stuff. Not that I should be spending the money.
So while the plan was to get the low end dialed in and then do the MTM when I had the cash to do it. Now I'm guessing the sandbox is on the back burner. BUT, it will be getting added to the system in the near future. Maybe I'll sell some stuff that's laying around.  :lol:
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: WC on 18 Jan 2018, 04:27 am
How small of a room would the OB servo subs work in?

I have an L shaped room. The top of the L is 8' long x 9' wide. The bottom of the L is 8' long x 17' wide, but the usable space is more like 8' x 11' with the 11' wall having an opening to another room 30" tall x 10' wide up 30" from the floor. 8' tall ceilings. Could it work on the 9' wall at the top of the L or at the wider 11' space at the bottom of the L (with the wall opening)?
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Captainhemo on 18 Jan 2018, 05:07 am
You can pretty much place them right up against a side wall as there are nulls  to the side of each  sub. But, you need  to have the sub towers pulled out  at  least 3' from the  front wall so there is room behind them.
I think Mike is using a pair  in a prety small  space with good results,  12' by  12'  if memory serves me  right  ?

jay
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 19 Apr 2018, 12:39 am
I decided to try my hand with the Transtint. I'd never worked with it before but I got my color all dialed in on some left over Walnut veneer. When I dyed my first MTM I got some areas that tinted extremely heavy for some reason. I think working in the sunlight, even though it was only 50* that day may have done it? From a suggestion of another member I got the majority of the tint off with denatured alcohol.
Disaster narrowly averted.

(http://www.audiocircle.com/image.php?id=178871)

(http://www.audiocircle.com/image.php?id=178873)
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 19 Apr 2018, 12:50 am
I took Ed's great idea on the wave guide and veneered it in the same fashion. I tried making my margins a little tighter because I didnt' want to try the sandpaper trick. I ended up being just a smidge shy on the length and will hit that area with some concentrated tint on a fine brush. I also planned on doing the area that will be closest to the wave guide in black paint. My 10ml paper backed veneer did not want to bend like Ed's did. I did not try the softener, that may have helped?  If I could do it over again, I would have either chosen a burl for the wave guide area or done 4 wedge shapes instead. I'm not a huge fan of the way the grains work against each other here.
(http://www.audiocircle.com/image.php?id=178868)

(http://www.audiocircle.com/image.php?id=178870)

(http://www.audiocircle.com/image.php?id=178998)

(http://www.audiocircle.com/image.php?id=178999)

(http://www.audiocircle.com/image.php?id=179000)


Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 19 Apr 2018, 12:55 am
I have not figured out yet what will be going over the Shellac yet for a top coat.
I used a simple wagner sprayer that I had purchased at HD for less then $100 to spray some stains on patio furniture. It worked well enough. I actually have a nice HVLP gun but have not set up a compressor appropriate for it's usage yet.

The look I'm going for is this repro Klipsch. I just have to figure out the grill cloth. Klipsch used a lambswool and I'll likely use this in a lighter color. It is what a lot of other vintage speaker builders have really liked.
https://www.123stitch.com/cgi-perl/itemdetail.pl?item=59-135X


(http://www.audiocircle.com/image.php?id=179001)
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 19 Apr 2018, 01:01 am
Thought you might get a kick out of this and someone might find it actually useful. The woofer boxes are the perfect size to be able to spray the tops of the cabinets easily and still get the bottoms too. I think my cabinet is built slightly larger then the pre cut units. But the cabinet is proud by about 1/2" on all sides from the size of the box. Perfect for spraying! Haha.
With the pre built cabinets being slightly smaller, you could still just cut some 3/4 x 3/4"sticks to put under the cabinet and you would be good to go.

(http://www.audiocircle.com/image.php?id=178997)
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: gregfisk on 19 Apr 2018, 06:19 am
Your speakers look really good Flavo!

I used to have a pair of those Klipch speakers and the finish looked just like that. :thumb:
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Captainhemo on 20 Apr 2018, 05:02 am
Nice  Mike !!
The veneer softner  would have helped  a lot in my experience.. pick up a    jug from  Veneer Sup0plies,  it'll  last you "forever"

jay
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 21 Apr 2018, 02:32 am
Your speakers look really good Flavo!

I used to have a pair of those Klipch speakers and the finish looked just like that. :thumb:

Awesome! I just picked up my grill cloth this evening and it really pulls it together.


Nice  Mike !!
The veneer softner  would have helped  a lot in my experience.. pick up a    jug from  Veneer Sup0plies,  it'll  last you "forever"

jay

The next time I need to do anything like that again I will definitely pick some up. Live and learn :-)
By the way. I like your version of MDF much better then the stuff I've used in the past.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: gregfisk on 21 Apr 2018, 07:35 am
In regards to the grain on the waveguide, you are being way too picky, just like I would be :duh:.

No one is going to even notice that the grain goes a different direction. It looks so darn good having the grain in there that that's all people will see.

You really did do a nice job with the finish :thumb:

Greg
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 29 May 2018, 02:15 am
In regards to the grain on the waveguide, you are being way too picky, just like I would be :duh:.

No one is going to even notice that the grain goes a different direction. It looks so darn good having the grain in there that that's all people will see.

You really did do a nice job with the finish :thumb:

Greg
Thanks Greg, I really appreciate the words of encouragement. After the finish, you could not have been more right.  I'm completely happy with the way the inlay turned out along with the general finish of the cabinets.
(https://www.audiocircle.com/image.php?id=180606)
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 29 May 2018, 02:18 am
And some random shots from this weekend. At this rate I should have them buttoned up by early 2118  :lol:


(https://www.audiocircle.com/image.php?id=180602)

(https://www.audiocircle.com/image.php?id=180605)

(https://www.audiocircle.com/image.php?id=180022)

(https://www.audiocircle.com/image.php?id=180609)

Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Early B. on 29 May 2018, 02:46 am
Utter awesomeness.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Tyson on 29 May 2018, 05:22 am
Agreed, that's niiiiicceee work!!
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: pdg540 on 29 May 2018, 07:21 am
In regards to the grain on the waveguide, you are being way too picky, just like I would be :duh:.

No one is going to even notice that the grain goes a different direction. It looks so darn good having the grain in there that that's all people will see.

You really did do a nice job with the finish :thumb:

Greg

Are you commenting on the great cabinets the OP has created here?
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 29 May 2018, 12:16 pm
Thanks guys!!
I've been pretty slow with them but am really enjoying how they're coming out.


pdg540, I was complaining out my veneering in the waveguide earlier and Greg was talking me off the ledge   :D
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Danny Richie on 29 May 2018, 01:51 pm
Man, that looks great.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: pdg540 on 29 May 2018, 03:25 pm
pdg540, I was complaining out my veneering in the waveguide earlier and Greg was talking me off the ledge   :D
[/quote]

Right on! Just wanted to be sure what product he was talking about.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 30 May 2018, 06:11 pm
Man, that looks great.

Thanks Danny, I really appreciate that. As do I really appreciate you putting this stuff out here for us.


And just because I want to. Some more pics.

Woo Hoo!

(https://www.audiocircle.com/image.php?id=180679)

A close up of the linen I chose against the finished cabinet.

(https://www.audiocircle.com/image.php?id=180678)

And the copper playing off the tones in the wood along with a little natural light behind the wave guide is pretty spectacular.

(https://www.audiocircle.com/image.php?id=180677)
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Tyson on 30 May 2018, 06:21 pm
Dayum!!
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: gregfisk on 30 May 2018, 07:19 pm
Flavo,

Those are just plain gorgeous to these eyes!!! Man you did a nice job.

When something looks this good in a high gloss you know the work is top notch.

Enjoy looking and listening to those wonderful speakers!

Greg
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Danny Richie on 30 May 2018, 07:54 pm
So what do we have over there in white with black rims?

(https://www.audiocircle.com/image.php?id=180679)

Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 30 May 2018, 11:22 pm
Very much appreciated everyone. Really.
Wait until I show you all my fancy shop.  :lol:

So what do we have over there in white with black rims?

I saw you were a Vette guy. This is my first American muscle car. I've always had little German stuff, but have had a burning for a 00-04 GT for a long time now. So I did it.
It's set up a bit aggressively for track instead of the around town driving it actually does. It's probably the stiffest street car I've ever been in. LOL
The "roots" style Eaton blower allows for instant on with the torque though  :thumb:
And I vinyl wrapped it. It's actually a light grey but it's nearly impossible to photograph with my phone and see that.


(https://www.audiocircle.com/image.php?id=180722)


(https://www.audiocircle.com/image.php?id=180723)
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Danny Richie on 31 May 2018, 12:27 am
Very cool! I love it.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Captainhemo on 31 May 2018, 05:37 pm
Nice job  man,  on all the projects 
Love the veneer work ,  gorgeous


jay
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: ebag4 on 31 May 2018, 09:54 pm
Mike, those turned out fantastic, great job, love the veneer.

Best,
Ed
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: mlundy57 on 1 Jun 2018, 12:14 am

(https://www.audiocircle.com/image.php?id=180679)


Does the width of the chamfer decrease from front to back or is that an optical illusion?

Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 2 Jun 2018, 12:29 pm
It does indeed. It has two different angles going on there.
Although not the easiest to see what's going on. This is how I set that up.

In this first pic, I've cut more off of the back of the cabinet base.
(https://www.audiocircle.com/image.php?id=180019)

In this one, I'm cutting more of an angle in the front. The fence was there just to help my eye. Once the blade was up, the fence was moved out of the way.
(https://www.audiocircle.com/image.php?id=180020)

Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 2 Jun 2018, 08:31 pm
Any reasons why this layout won't work?
I hope not as it's semi permanent at this point  :?

(https://www.audiocircle.com/image.php?id=180839)
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: gregfisk on 2 Jun 2018, 08:45 pm
I think someone who knows what they're talking about  :lol: would say to take the center coil and turn it up on it's side. Then face it so it looks like it could roll back and forth between the other two.

They may be far enough away from each other not to matter though :dunno:.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 2 Jun 2018, 08:49 pm
At least that one's not hot glued down! Haha. I don't think I'll be able to get it to fit in the cabinet that way. But I could center it better away from the others.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Tyson on 2 Jun 2018, 09:05 pm
I think someone who knows what they're talking about  :lol: would say to take the center coil and turn it up on it's side. Then face it so it looks like it could roll back and forth between the other two.

They may be far enough away from each other not to matter though :dunno:.

Yes, I'd orient that middle coil vertically so the electric fields are adjacent to each other.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: gab on 2 Jun 2018, 09:24 pm
Yes, I'd orient that middle coil vertically so the electric fields are adjacent to each other.

From Loudspeaker Design Cookbook: "In making physical placement decisions about inductors on a crossover board, place them as far apart as possible and mount them at 90 degree angles to each other. If you maintain at least 3" of separation and right angle mounting, you will avoid magnetic coupling between different sections of the crossover."

gab
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 2 Jun 2018, 09:49 pm
Now that is some damn good info right there Gab. I wish I had seen that before I built this.
My typical fashion  of winging it has bitten me.
I can get them farther apart but all in the same plain. What happens if I squash the coil a bit? It's 2.25" right now and I'm not going to get it vertical without redesigning my already built cabinets.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: gab on 2 Jun 2018, 10:02 pm
Any reasons why this layout won't work?
I hope not as it's semi permanent at this point  :?

(https://www.audiocircle.com/image.php?id=180839)

Flavo - if you can't lift that middle inductor due to height, I'd get it as high as I could in the enclosure and then relocate all 3 inductors as far away from each other as possible which means the corners for the top and bottom and far left for the middle. Or you could find another location for the middle inductor far away from the other 2 (i.e., outside the crossover box). Or hope for the best I suppose with what you got! You wouldn't be the first! Good luck and let us know where you end up. Great woodworking BTW.

Edit - did you see this layout info courtesy of Troels? Top of pg 7

https://www.audiocircle.com/index.php?topic=83325.120



gab
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 2 Jun 2018, 10:26 pm
Thanks for that Gab, that's definitely very helpful.  I can see now, looking back, why Ed's X-O was laid out as it was. I'm going to go with your suggestion of getting all the coils as far apart as possible for now. If the design ends up not working, will it be audibly obvious, or just not as good as Danny designed it?
I.e., do you think I'll be able to tell? In which case I'll probably build the X-O externally.
Thank you
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 2 Jun 2018, 11:45 pm

I certainly haven't made it any prettier.
But maybe this will work?

Danny, when you were designing this, where did you envision the X-O board would go?
I'm considering just building it separately and having it outside the cabinet.

(https://www.audiocircle.com/image.php?id=180841)
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Captainhemo on 3 Jun 2018, 05:41 pm
Mike, when I came up with the cabinets I figured most  would  just  place the networks on top of the bases behind the  lower  M165NQ ( why we left a bit of extra space below that lower  woofer.)  Basically it was the same  idea as the   full size Otica's and  Wedgies..
Figured if  some wanted  to hide them, they'd get  creative as you've done Unfortunately, you  have the one little  glitch in your  layout :(.

As for that inductor,  I don't think you'd actually   notice   any   obvious  change, it'd be subtle but  you    may  have some slight interference  and  a difference in the response.
that last  layout  is about as good as you're gonna get without flipping at least one  inductor on it's edge
If you   re-wired it   and put the  large low pass inductor in one  corner,  the    tweeter  inductor  in the opposite ( on diaganol) corner  and the  small  LCR   in between them on  it's edge, you   may have  enough height  clearence .  not sure

jay
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: mkane on 3 Jun 2018, 08:48 pm
  Great thread and could be my next build. Are the  Otica's still available as a flat pack. thanks
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: gab on 3 Jun 2018, 09:44 pm
Flavo - I think if I were in your shoes, I would go with your latest layout, although I don't have a frame of reference as to the center to center distances on the inductors. If its like 8" between centers, I'd try it out before more drastic measures. You could also rewire as Jay suggested above. Maybe Danny can weigh in here.

gab
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Danny Richie on 3 Jun 2018, 10:19 pm
The placement of the one in the middle is fine, just turn it up on it's edge.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 3 Jun 2018, 11:36 pm
The only way I could get the coil on it's side is if I squash 3/4" out of it in a vice. I could route holes in my cabinet that could accommodate that. I'm guessing that's a no no though?


They sound great to my complete amateur ear so far. I've had them running all day in the garage/shop.  Jay mentioned that I might get an off response. I'm assuming that would be noticeable if and when measurements were taken? Turns out I've got a friend that travels the world training people how to use software to set up for concerts and such and is planning on coming over to measure and help me set up at some point.
Is there a base line I'm looking for that I can give him, that would either be on or off if my X-O needs to be reworked? 

This is the company I'm referring to FWIW.
http://www.rationalacoustics.com/about/
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: mkane on 3 Jun 2018, 11:43 pm
  Great thread and could be my next build. Are the  Otica's still available as a flat pack. thanks
[/quotthanks
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: S Clark on 3 Jun 2018, 11:50 pm
The only way I could get the coil on it's side is if I squash 3/4" out of it in a vice. I could route holes in my cabinet that could accommodate that. I'm guessing that's a no no though?


They sound great to my complete amateur ear so far. I've had them running all day in the garage/shop.  Jay mentioned that I might get an off response. I'm assuming that would be noticeable if and when measurements were taken? Turns out I've got a friend that travels the world training people how to use software to set up for concerts and such and is planning on coming over to measure and help me set up at some point.
Is there a base line I'm looking for that I can give him, that would either be on or off if my X-O needs to be reworked? 

This is the company I'm referring to FWIW.
http://www.rationalacoustics.com/about/
The coil arrangement aligns the fields to overlap (and interact).  Fortunately, you've got them several inches apart, so I doubt if it's much of a problem.  Leave it.  Not worth trying to modify to turn that middle inductor. 
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 4 Jun 2018, 12:04 am
  Great thread and could be my next build. Are the  Otica's still available as a flat pack. thanks

Thanks! They are definitely available still.
If you like this thread, be sure to check ed's (eBag) post as well. I found it very helpful when making my set up.
When I'm on my PC I'll look up the link and post it.
Any questions please feel free to ask.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: flavo on 4 Jun 2018, 12:06 am
The coil arrangement aligns the fields to overlap (and interact).  Fortunately, you've got them several inches apart, so I doubt if it's much of a problem.  Leave it.  Not worth trying to modify to turn that middle inductor.

Right or wrong, I'm going with this! HAHA.

I'm hoping it's fine and appreciate your thoughts.

I'd still like to know about the measurements though, as I've got a pro who will be taking some:
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: mkane on 4 Jun 2018, 03:55 pm
flavo, thanks. I have read every post I can come up with concerning the Otica. If I can get them as a flat pack with drivers that would save a bit of searching. I was hoping Richie would chime in
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Captainhemo on 4 Jun 2018, 04:03 pm
  Great thread and could be my next build. Are the  Otica's still available as a flat pack. thanks

We're in the middle  of migrating to a  new CNC  shop, it is taking longer  than  we'd thought.
behind on a  few orders  but trying to replenish stock asap

they are sold in a complete kit though, you'll get  all parts needed, drivers & screws, cross over parts,  wire, solder, shrink tube,  tube connectors,   and the  cnc'd  flat packs  that are  easy to assemble.


jay
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: mkane on 4 Jun 2018, 04:44 pm
  Jay, can't thank you enough for your post. The kit is what I'm looking for. I would be grateful if you could post a link where I could get on a waitlist. Thanks, MKane


Edit: room is 26x17
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: mkane on 4 Jun 2018, 04:47 pm
   And, how about an opinion on going active with these. As of late I'm on a D Class amp kick and using a Nini DSP.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: Chops on 4 Jun 2018, 04:51 pm
(https://www.audiocircle.com/image.php?id=180723)

Nice torque curve and solid power. Looks like the same curves as mine, except mine are at slightly lower numbers.
Title: Re: Otica h-frame MTM questions for Danny and Ebag4 plus other stuff
Post by: rockdrummer on 2 Jul 2018, 01:04 pm
Flavo, what did you end up powering your oticas with? Are you running the 2a3 set you originally planned on? Do you get enough volume from the 3.5 watts? Also, love the dark tone with the light linen cloth. Gorgeous retro look.
Ben