Update on my design, and some driver pr0n!

[Spkr_Bldr]

http://www.diyaudio.com/forums/showthread.php?s=&threadid=128394

I find myself that the speaker cabinet with very extensive bracing somehow has a much wider sound stage. It's a combination of factors and resonance transfers.
I am also assuming that slots on the sides were cut to be filled with sand?
I myself don't have a CNC and do this type of work old fashion way.
If you are in NY we could have a shootout. :...:
Nice work.

Nothing can kill imaging like a resonant cabinet with nasty diffraction effects, both of those are a none issue with this construction. The slots are filled with expanding urethane foam ... resonance control isn't an issue, the only remaining possible issue with this construction is sound transmission through the walls. The foam is much better at knocking transmission levels down than some sort of epoxy/sand mix would be.

Even when glued up the threaded rods are important. Accelerometer testing will show exactly, but it's clear just from the knuckle test that any resonances are pushed significantly higher when they're tighetened down. And of course they also make it a snap to line up the layers for gluing. I also did a removable baffle that for now is a contrained layer construction, as are the top and bottom panels. Later I might go to something like an aluminum or phenolic baffle. The crossover is in a separate sealed chamber at the bottom. And you may or may not believe me, but I have a pair of cabs made from MDF as well, and the Baltic Birch ply version seems noticably more dead. The ply is of course 3x the cost of MDF, but if you're going all out it's worth it.

One thing you can do with MDF to stiffen it up quite a bit is inside and outside give it a couple loads of shellac, then on top of that brush a couple coats of epoxy.

You're free to drive to St Louis for a shootout, or just buy a pair Good luck with your build! Might I suggest using 15w's Revelators for your mids however? In my experience they're much more natural sounding in the 800-2500hz range. And in a 3-way you don't need the extra extension. I also love the Seas W16NX's.

 

[R-Carpenter]

I'd like to suggest, if I may, silicon carbide and powdered glass to fill the slots. Any local sand-blasting shop will be more then happy to give it to you for free. I've measured this materials and the results are very good down to 500hz but not as an epoxy mix. Just plain powder.
I am somewhat surprised that Baltic Birch is better then MDF but I like HDF such as Medex, Medine or Ranger board myself. MDF is not my preferred material all thou it's cheap.
My cabinets will take similar cutout on the front section for a baffle panel.
Did you attach the magnets to bracing? It's been my dilemma for a while.
I hear you on W15s. Unfortunately, circumstances have forced me (haha what a spoiled kid ehh) to use W18 revelators. I've tested them already. They are exceptional drivers IMO. The build quality is second to none.
I wish I had time to drive down there but oh well.
I also think, the price on your speakers is great given the cabinetry and driver compliment.
Are you going to veneer the sides in the future?
Roman.

 

[Spkr_Bldr]

Those are some great looking speakers Ryan. All I can say is sign me up once you have any of the final speakers ready. I am looking to do a major upgrade to my 2ch system once we buy a new house in 2 years or so I will definitely be interested in your speakers with the RAAL ribbon.

Thanks man, the vote of confidence means a lot!

These are definately aimed at 2-channel listening. They'll deliver acceptable for most extenstion in small-mid sized rooms, but of course like any 2-way bookshelf adding a subwoofer or two will only make them better. If you want something that's totally tranparent, casts a huge stage, and gives accuracy and detail then these are a great option.

If you're looking at 2 years down the road it's pretty hard to imagine how many options I'll have at that point! I'm already working on MTM's with matching center channels, a floorstanding open baffle with this construction cabs on the bass at the bottom, a big floorstanding WMTMW, a smaller width version optimized for 5" driver MTM's, and multiple versions with custom milled waveguides.

I don't believe in a house sound, and I don't believe any one way or approach is best. Just look at last years RMAF speaker, open baffle midrange and waveguide tweeter. It was spectacular, but so is this, and so will be other designs. I'm just here to build excellent speakers and give the customer options. The one thing I'll never build is a speaker that rides the ragged edge of being overly analytical and harsh, everything I build will be balanced enough that you can listen to the vast majority of your library without bleeding ears.

 

[Spkr_Bldr]

I'd like to suggest, if I may, silicon carbide and powdered glass to fill the slots. Any local sand-blasting shop will be more then happy to give it to you for free. I've measured this materials and the results are very good down to 500hz but not as an epoxy mix. Just plain powder.

Well that's an intereting option. The air from leaving it in powder form would serve the same purpose as air in the expanding urethane foam. I'll probably try both and measuring with an accelerometer, and using a guitar pickup mounted on the side of the box to measure transmission. Thanks for suggesting it!

I am somewhat surprised that Baltic Birch is better then MDF but I like HDF such as Medex, Medine or Ranger board myself. MDF is not my preferred material all thou it's cheap.

I've used some products sold as HDF before and didn't see much if any difference myself. In fact the cabinets I have in this construction were cut with "HDF", but who knows what the product name is ... I thought all Medex and Medine are is mold proof and/or flame retardant products, and were made under the same pressures as MDF.

I've seen some data on Youngs Modulus of certain wood products, but who knows if I could find it again. All I remember is that MDF was at the bottom, and void free Baltic Ply was about 4x as stiff.

My cabinets will take similar cutout on the front section for a baffle panel.
Did you attach the magnets to bracing? It's been my dilemma for a while.
I hear you on W15s. Unfortunately, circumstances have forced me (haha what a spoiled kid ehh) to use W18 revelators. I've tested them already. They are exceptional drivers IMO. The build quality is second to none.
I wish I had time to drive down there but oh well.
I also think, the price on your speakers is great given the cabinetry and driver compliment.
Are you going to veneer the sides in the future?
Roman.

No, I'm not attaching the magnets to the cabinet. I personally see no benefit in doing that in this case, only if your cabinet flexes to begin with ... or if your drivers have flimsy frames.

I've used the W18 Revelators myself many times. Of course they're wonderful drivers, I just find the W15's less colored through the midrange on actual listening tests. The W18's I think have just a touch on honk to 'em in that range. One new driver I can't wait to get and evaluate is the new Eton Symphony's. Unfortunately they're Revelator priced, but they have a much more advanced motor, and paired with the wonderful Eton cones could be a real winner! Morel also has a new driver out with lots of copper in the motor (a Morel first), much better mechanical suspension, and a multi-layer damped Kevlar sandwich cone.

It'll all be veneer'd by mid-week next week. I'm probably going to re-do the baffles with a 4-way bookmatch of Thuya Burl and do the sides in Tineo. The Tropical Olive I used in the picture just didn't turn out flashy enough for me.

You're right, I won't be making much at these prices ... the drivers alone are pushing $1500 my cost. But initially getting some pairs on the market and get people talking is what I need.

 

[Spkr_Bldr]

More progress, the hi-end design is pretty much finalized ... just a bit of finishing work on the cabinets and getting the cabinet tuning right where I want it. We had a great get-together last night at a local friends house, 6 people attended and all thought these were something special. They're just completely transparent, they're fast, accurate, and image like crazy. Bass right now is I think very well balanced, some thought it was a bit light ... so that's all that's left to work on.

Here's pics from today when I brought them back home setup in my 2nd listening room. The veneer that's on the left baffle and the right cabinet is Tineo, that's what they'll be done in completely. The baffle on the right is Tropical Olive, I'll re-cover it with the Tineo. You can see the separate crossover section at the bottom too.

 

[kevin k.]

Extraordinary looking speakers, Ryan... thank you!

The Tineo veneer, judging from your pictures, would be my choice, as well.

Do you have any pictures of the crossovers that'd be willing to post?

Thanks again.

 

[Spkr_Bldr]

Extraordinary looking speakers, Ryan... thank you!

The Tineo veneer, judging from your pictures, would be my choice, as well.

Do you have any pictures of the crossovers that'd be willing to post?

Thanks again.

Thanks for the kind words Kevin ...

Veneering is one of my favorite parts of speaker building. I have probably 40 different species that I've accumulated over the years, all exotic and unique. Nothing beats the first wipe with Tung Oil on a new sheet of freshly laid veneer

I can take pics if you want, but the crossover is nothing complex at all. That's part of the point with this design, well behaving drivers that integrate with minimal components. They're definately top of the line components though, 12ga foil coils on the woofer and 14ga on the tweeter, ClarityCap MR caps with Teflon V-Cap bypass.

 

[mazersteven]

Speakers look great. I like the 2-tone wood look.

 

[jamie2112]

They do look great. I will audition them free of charge.....

 

[kevin k.]

Thanks for the kind words Kevin ...

Veneering is one of my favorite parts of speaker building. I have probably 40 different species that I've accumulated over the years, all exotic and unique. Nothing beats the first wipe with Tung Oil on a new sheet of freshly laid veneer

I can take pics if you want, but the crossover is nothing complex at all. That's part of the point with this design, well behaving drivers that integrate with minimal components. They're definately top of the line components though, 12ga foil coils on the woofer and 14ga on the tweeter, ClarityCap MR caps with Teflon V-Cap bypass.

You're most welcome. And please don't worry about the crossover pictures... your reply says it all.

What of the impressions by some that the bass was "light"? Have you had any time to determine for yourself? And, if so, what might you do to correct the situation?

Another question for you... What makes you think a change from the Audio Technology driver to the new Scan Speak Illuminator might be preferable?

Again, beautiful speakers, Ryan. Thank you.

 

[jamie2112]

The stands are very nice as well. Great job on these.....

 

[Spkr_Bldr]

You're most welcome. And please don't worry about the crossover pictures... your reply says it all.

Thanks for not putting me on the spot too much, I'd like to wait until they're officially on the market before giving anything more away. Very pricey components, but when you reach this level of transparency and articulation you can notice differences that would otherwise be lost in the hash.

What of the impressions by some that the bass was "light"? Have you had any time to determine for yourself? And, if so, what might you do to correct the situation?

Yea, absolutely. A couple things were the problem, one my ports were way off from simulation. One cabinet was tuned to about 59hz, the other was around 55hz ... obviously that's not what I was going for. So I had to make some custom ports with right angles to get the proper length, but they're both now tuned to 41hz just as I wanted. Also one of the cabs had a couple points where it was leaking pretty severely, losses in a vented cab have major impact on port response. And the final thing was just playing with stuffing and making measurements to get things right where I wanted them.

Still it's a bookshelf, and it's not going to rattle windows, but it is more balanced with just a touch of warmth now. It's enough to run full-range on it's own now and give satisfying bass energy and extension (I measured down into low 30's in-room with RTA software, +/-5db), but when I add the sub in and cross it at 40hz it's an even better experience.

Another question for you... What makes you think a change from the Audio Technology driver to the new Scan Speak Illuminator might be preferable?

Well, the Illuminator models like you wouldn't believe in regards to bookshelf bass extension. Assuming it performs like the preliminary spec-sheet says, we'll be talking about a F3 of around 34hz, and in room down solidly into the 20's. It also has much more xmax and SPL capability. The only question mark with it is a big one, how will it sound? But I have the utmost confidence in the ScanSpeak Engineers, I'm sure it'll deliver the same or greater levels of detail, speed, and transparency as the AT driver.

Again, beautiful speakers, Ryan. Thank you.

You're making me blush Once I get the veneer finished this week, oiled and gloss lacquered up, then they'll be something!

 

[Spkr_Bldr]

The stands are very nice as well. Great job on these.....

Ha, well those are the cheap Parts Express stands ... then I just put a cabinet slice on the top plate so the spikes in the bottom of the cab would hit it. I have a pair of the Swans Diva stands coming mid-week that'll be modified to work with these. Basically just adding a top plate the same shape as the cabinet and mounting milled aluminum spike footers. That combo should look really nice, the Diva stands have a shape that I think will be very complimentary to these cabinets.

 

[jamie2112]

Well your design had me fooled . Once again great job and I can't wait to see the finished product.....

 

[Spkr_Bldr]

Well your design had me fooled . Once again great job and I can't wait to see the finished product.....

Haha, even crappy stands look nice with sexy cabs sitting on them Thanks for the compliments. Lots more pictures and updates coming this week! I'll have the other two designs up and running very soon.

 

[asterduc]

this topic was forwarded to me due to the fact that I am using the 'layer-technique' for some years now.
Please allow me to join this conversation.

CNC routing has created an easy way to build up an enclosure with layers, using a lot of freedom in the internal and external design.
Although the 'layer-design' looks spectacular, it is not obvious to make this concept better than the regular 'boxes'. Some thinking and experimental work is necessary to reach a succesfull result.

I agree with Ryan, that if he offers it for those prices, you will get a lot of speaker for the bucks. I have been calculating them myself and if I was going to offer my Concave (see my webpage), then price would have to be around 10.000 euro/pair.

MDF / Plywood: I have found that MDF 'sound' less than MDF. I do not call this an advantage or disadvantage. It is only different. I am now using some kind of MDF that has different specs. E-modulus, weight, surface and grain or specifically made for the layer-technique.

Regards,
Ed.

 

[Spkr_Bldr]

Hey Ed, Welcome!

Your design looks beautiful, I looked through your photo gallery. There are a lot of similarities between what we're doing ... but it's easy to see why yours would cost significantly more. More drivers, more cabinet slices, more labor, etc. How you routed out the circuit board for your crossovers is pretty cool! I did that with Forstner bits for the big inductors, just so they'd be more secured in shipping ... but certainly not to the extent you did. Excellent work all around on your design!

The only bad thing I can see about this style of cabinet is all the sanding!

I personally think high quality, void free, 14-ply Baltic Birch ply is the best wood based cabinet material on Earth. Some of the various 'new' HDF formulations are better than traditional MDF, but I believe they're inferior. However this type cabinet construction is so much better than standard boxes that you could probably build it out of particle board and still realize a cabinet with no colorations.

I'm sure my design will evolve over time, with the ease of making programming changes to the CNC machine, why not. But the performance is already there, changes would be made to make assembly easier or to add more flexibility.

 

[asterduc]

hello Ryan,

thanks for the reply.
You are right about the sanding, but that was 3 years ago when I bought the CNC router and didn't know how to handle these things. Resulting in a lot of errors and extra work.
I am still not an expert with it, but the Mk2 does not need that intensive sanding anymore.

Making the layer peaces is easy, but the preperation to let all parts fit together properly, is another thing. And that is what this concept needs. Good thinking, good programming and good preperation. As a woodworker it takes you some time to think that way.

Anyway, I am glad to see that others think in this multi-layer-technique direction too. It's a new way to improve an enclosure and it allows you to go away from the classic designs.

I hope you will put some more information available on the web about your system, so that I can verify it with my findings. You can find mine through the link on my webpage, just try all the shortcuts and you'll get there. Allthough they are written in dutch, the pictures and graphics are multilanguage!

MDF: I will defenitely try the multilayer Birch Plywood too, but for my current experiments I stay with the special MDF.

Filter board: yes, that was indeed a cute idea that many liked. Only the MDF board is on the foto gallery I believe. The final PCB was made out of black HPE and looked great too.

Regards,
Ed.

 

[Spkr_Bldr]

Again, beautiful work Ed ... just keep doing what your doing without any influence from myself. Then maybe in 6 months lets talk and share what we've learned

How's this look for a FR curve? Measurement taken at 1m, 1/6 octave smoothing, on tweeter axis, 9.5ms gate time.

 

[asterduc]

Then maybe in 6 months lets talk and share what we've learned

good idea.

How's this look for a FR curve? Measurement taken at 1m, 1/6 octave smoothing, on tweeter axis, 9.5ms gate time./QUOTE]
not too bad, looks like the RAAL is a great deal. Are the off-axis in the same line? I've tried to get in contact with Alex for a pair of these some time ago, but never received a reply from him. Lucky you!

Enclosure: I would appreciate to see a near-field measurement on the woofer. The LMS measurement doesn't show what the mid/woofer does, due to the setting of the timeframe.
Put the mic at about 1 or 2 inches from the bass driver and measure without smoothing or timeframe (no cut-off on the responce curve).
If your measurement is right, then you should see the standing waves in the enclosure (they are much lower than with classis style encloseres, although unfortunately still there).

Regards,
Ed.