Are you saying you like plywood covered in a veneer? Typically when you say birch plywood, it references a layered material with a birch face veneer.
My preference is for figured veneers (fiddleback anigre, waterfall bubinga...) with a precatalyzed lacquer finish - hand rubbed appearance, not high gloss. As far as cabinet material, I've been using mdf lately, but am interested in using 12 layer plywood material in the near future. |
Baltic birch plywood with veneer over it. I use MDF but only with paint or laminate. Bubinga is 1 of my favorites but I use solid bubinga over birch ply. 1 of the few hard woods that's stable. I use a lot of US sourced Cherry veneer. Since most of what I build is large veneer costs add up fast. I have a good source for great looking cherry veneer. I have tried carbon fiber, fiber glass, Corian, Plexiglas,Aluminum,HDF, MDF. Many other plys, hemp, apple, mahogany. Still to my ears quality birch ply with full veneer french polish has a more pleasing sound. The other quality plywood's are near as good as the Baltic if you double, if you go 3/4in Baltic birch ply is best. Since a 3/4in T. cab even fully braced adds much resonance to loudspeakers sound. |
MDF is a pretty poor material for the application if performance is your criteria. It's popular because it's cheap and relatively easy to work with. With ply there are factors which determine it's performance, both the resin and layers used are critical ... and ply with poor quality interior layers are everywhere, much of it I've seen lately has come from Russia. But if you can find a source for quality void free Baltic Birch ply, I think it's the finest enclosure material available to the hobbyist.
As far as veneers go, there are just too many to choose a favorite. I like the high contrast, heavy grain and figuring type veneers ... the ones that jump out at you!
I've had nice results from hand rubbed finishing as well, like French Polish ... the types where you wet sand the finish oil into a slurry and let it dry to fill pores. I've also had nice results with sprayed finishes like Poly, assuming you prepare the veneer first to bring out the character. |
Baltic Birch layered with MDF is an excellent material for turntable plinths, particularly the Lenco. It is easy to work with, affordable, readily available and best of all, it has properties which absorb vibration. This is evident in analog playback- pace and rhythm, defined, articulate bass.
I have never used it for any other applications, i.e. speaker cabinets. But, I can only guess that it has similar qualities with regards to speaker construction which I find to be so desirable. |
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HDF (high density as opposed to medium) with laminate inside and out. Bracing is very important. |
The best cabinet material is air! I like planars. |
Interesting. . . in most cases, Baltic Birch is not from the Baltic region. . . it usually denotes a somewhat hiher grade birch ply from Russia, Bielorus, or China. Finnish birch instead. . . is a different kettle of fish. One of the highest grade materials I have found is from Finnish fabricator UPM, which can be sourced in thicknesses up to 50MM:
http://w3.upm-kymmene.com/upm/internet/cms/upmcms.nsf/$all/af4c54532110776dc22570ba00304034?OpenDocument&qm=menu,4,5,1&smtitle=Plywood
Material uses outdoors bonding agents and has 21 plies on the 1 inch thick product. This appears to be higher grade material than what is usually called 'baltic' or 'marine' plywood. G. |
I bought some Hawaiian Koa veneer for the ProAc 2.5 clone project I have planned. |
Solid wood all the way. My Audio Note speaker cabs are custom made using Indian mahogany which is the same species as Cuban mahogany. Water stain, shellac and Sutherland Welles tung oil.
More volume...more natural..more bass...more tweet...kind of like a great amp upgrade. |
The Baltic we use is Finnish I buy by the pallet to save $. If you source plys from most home centers its Chinese and lamination on this ply are terrible. Sometimes I can pull Chinese plywood apart with my hands!!!. Ive tried MDF ply, HDF ply and others in layers still to me Baltic and veneer with French polish gives best results for my loudspeakers. But my good friends a TT nut he uses layers on his plinths. I use aged hard rock maple for bracing this gives best tone. I have build solid hard wood cabinets but most split after a bit of time ,if I use hard woods I use over ply. Thank you for the posts. And happy listening. |
Johnk,
Your thread has got me thinking about the possibility of building the ProAc 2.5 clones using Baltic Birch plywood instead of MDF with veneer.
I know this would alter the sound of the speakers from their original intent. What are your thoughts on the sonic influence of this wood for box construction?
Thanks,
Dean |
MDF stores energy releases as slight delay adding coloration to sound if fully braced you can work with it. But baltic birch plywood doesn't store releases energy so the coloration's of birch plywood are pleasant the coloration's of MDF tend to be narrow in frequency and can add a unpleasant delayed coloration. So a doubled 3/4in Baltic cab for your proac would be a improvement in sound quality. The French polish penetrates veneer so resonates more even in frequency and at a greatly reduced level. |
Thanks, Johnk. I'll look into it. |
Not sure its is my favorite, but my VA PO's in the Big Leaf Quilted Maple are stunning! The fit and finish is on par with the very best I have seen.
Sonus Faber does some nice work too..
John |
Sonus is an interesting case. . . rather than constructing speakers with plywood, they layer selected veneers in place with crossing grains into a custom ply pre-molded to the shape of the speaker. I understand that the top models use over 20 layers of veneer. |
I use veneer layers for curves. |
Higher end Sonus speakers are more/less all curves. .. hence the heavy use of custom plies. According to Sumiko, by using these custom plies Sonus achieves higher rigidity/damping with low mass. G. |
walls. A 3 layer composite of: 1/2 in hdf, 3/4 in hardwood ply, 1 inch mdf. Braced with seasoned hardwood. |
Wilson benesch has some interesting information on their website wilso-bensch.com If you go to their newsroom and scroll down they show a list of materials and the speed which sound travels through them. Ideally you would want sound waves to travel quickly so the energy is not stored and released slowly. Their speakers are made with carbon fiber which dissipates the waves off the back of the driver much faster than other materials. In addition carbon fiber is very ridged so the cabinet itself does not move around and vibrate. If you play the violin or cello you should really look at the website of louis and clark. They make these instruments from carbon fiber. I believe they are very very good sounding. Most orchestras do not allow them because they want those instruments to have the wood look. As a dealer for wilson benesch I can vouch for benefits of that material, speed lack of coloration, and they disappear.
If you have a dealer near you take a listen. |
I know about the WB designs but thank you for the post. I have used Carbon fiber I found it worse sounding in my designs than the Baltic plys etc. Its also costly hard to work with. So I leave it to companies like W.B. When Stradivarius are worse sounding than carbon fiber maybe I will revisit. Other composites are available for cabinet construction. I had better luck with those over CF. Hope your sale are going strong 2009 will be a hard time for retailers and audio manufacturers alike. |
Johnk, the goals of cabinet construction for a string instrument and for a speaker are subtly different. . . a luthier uses the entire case of the instrument as a mechanically active amplifier. . . As such laminates like timber plies make for inferior student instruments because they lack the ability to propagate/amplify mechanical vibrations, not to talk about particle board which simply is anathema in cello/violin construction. The top of a cello is usually made from carved and finely graduated thin spruce. . . the bottom plate from almost equally thin maple or poplar. . . the two are mechanically coupled by an oaken post. . . . then of course there is the coupling to the strings through tailpiece, neck, and elastic maple bridge. The instrument is incredibly light and thin-walled, and vibrates and rings like it's going out of style. I haven't seen too many speakers that attempt to do the same. Hence, invoking the Cremonese masters is effective markcom, but. . . G. |
Paino Black with Clear Coat paint. |
I have to agree with Eldartford. No cabinet is the best cabinet. I love my stats. |
Guidocorona
I suspect you could build a speaker enclosure to operate like a fine string instrument.
You could make one, or perhaps even a matching pair.
There is almost no possible way, for a reasonable amount of money, to mass produce such an instrument.
As for a practical (advisory) perfect enclosure, why not concrete? Heavy and inert, it would add nothing to the sound of the drivers. Add dampening to taste.
I'll stick to my panels. |
Cerrot, How is your stat held? By frame metal or wood so is resonates just like a cabinet thus has coloration just like a cabinet. Don't believe place a stethoscope on material holding stat play music.. Also stats can have forward backward movements as membrane moves forward and back this cause planar to rock. Most designs don't fully address this thus all the aftermarket stat stands. And Guidocorona I fully understand the differences in musical instrument construction and loudspeaker cabinets. And a few loudspeaker in the market today have cabinets similar to a musical instrument construction. I don't offer for I feel designs are to colored. |
Johnk,
Actually, its a metal frame, but my point is that I don't (or didn't) want my drivers in a box. I have the Eros Mk II and, yes, the woofer is in a box, so I am kind of speaking out of both sides of my mouth but the 60hz or so sounds don't seem to be effected as much by box coloration as mids and highs do (and I do like going down to 28hz so need the hybrid design). In the price range of my stats, I haven't heard any box speaker that comes close. At multiples the price (I like the B&W 800d, Magico minis -only down to 40hz, and Kharma Ceramique), I would be happy upgrading but not looking to spend $20,000+ right now. Actually, I would go $20k+ but I would also need to upgrade my amps (eyeing either Ayre MXR for SS or shindo for tubes) and would also need to upgrade preamp to better match the amps. So, upgrading will run me close to $50,000 or so, so waiting. Speaker design has progessed greatly over the years and I have heard less (in the products mentioned above)or(almost) no cabinet coloration but, when I bought my speakers, in the price class, box speakers just didn't do it for me. |
Johnk, Sonus claims their cabinets are built like Cremonese string instruments of old. . . fabulously effective markcom. . . reality is different though. . custom ply cabinets of Sonus do not vibrate. . . they are desirably dead as doornails. But yes, it would be interesting to develop a speaker that truly vibrates like a fiddle. . . would probably be incredibly efficient. G. |
Magfan...I tried concrete once. Chimney blocks are a good size for a bookshelf speaker...all you need is front baffle and rear panel. Only problem is that concrete rings. Not dead at all.
Suggestion...try styrofoam, well braced and/or curved. It is dead. |
Not to belabor the point, but I was looking at an photo from the CES show a couple of years ago and found a photo of Vanderstein 5's. This was a special pair that Richard built using carbon fiber. Apparently the sounded great but I am sure production was very expensive. I think the Marten speakers are made from carbon fiber as well. My guess is that working with that material takes alot of research and would be tough to do in a garage. So we have three major companies that use/have used carbon fiber successfully. My guess is when you design with carbon fiber you probably would need an entirely different crossover and drivers. Not as easy as one would think.
I miss spelled the name of the violin company. There website is http://luisandclark.com/ . I doubt they sound as good as a Strat but when a 5K violin can sound as good as a 100K violin that tells me something. |
Soundsrealaudio, this is very encouraging. . . if you consider that it took about 500 years for fiddles to progress from early Moorish example to reach the greatness of the Cremonese masters. . . while contemporary luthiers have already achieved respectable results having experimented just for a few years with carbon fiber composits. G. |
The BEST cabinet is AIR, +1! I did replace the side rails on my Maggies with solid walnut, finished with Tung Oil though. |
Rodman
Tung Oil is good stuff. Hand rubbed to put a little love into those speakers. The music gods are smiling on you.
You are correct. The best cabinet would be no cabinet. That is clearly why planar speakers over the years have had an edge over box speakers. Of course there are problems with that as well. di-pole sound brings the back waves into the picture and encourages you to bring those speakers out from the rear wall more than you might prefer, then there is the issue of controlling the woofer. I think I was just reading a review of a speaker that does that with electronics. That makes my eyes glaze over...and my head to explode...
We will see where all this technology takes us. |
Mr Sounds- Yes, Tung Oil is great stuff and when applied with the bare hands: The body heat opens the grain a bit for an even deeper finish. Excellent way to bond with whatever you are finishing(gun stocks, audio cabinetry, etc). No problems with my planars and woofers. I've been actively bi-amping my systems with a pair of transmission line woofs for over 28 years now. The TLs can now stay in the corners(where woofers belong) and are aligned in the time domain by my TacT RCS 2.2X. I've always used TLs with my planars because the cone is basically unloaded, and can move fast enough(with a high slew rate/high damping factor amp) to provide a seamless crossover point. Do you ever spend any time in Indianapolis? |
Concrete blocks? Were they sand filled?
I was speaking to a system I saw once where the speakers were poured in place. I suspect the chimney block effort was sabotaged by the front/rear panels.
ALL concrete is the way to go! A couple inches of Portland will never rattle. |
I saw a pair of Usher monitors and stands recently with what appeared to be largely marble construction, unless it was a synthetic material of some sort like that stuff they use in countertops (Corian?). Very pretty and very heavy! |
Magfan...Chimney blocks have no voids to fill. Agreed that concrete won't rattle, but it will ring, and at a low frequency. |
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LOL!
Here is the correct spelling and definition:
http://en.wikipedia.org/wiki/Upsidaisium |
Upsidasium was the metal (mythical) discovered on Mt. Flatten.
Don't you remember Rocky and Bullwinkle?
Captain Wrongway.......but I'll save that for later! |
Just looked at link! Yep, as I remember......
Need a new thread:: 'rocky-bullwinkle trivia' |
Have you guys tried a french polish? |
John
I have had some speakers in house made from birch plywood. What a relief over MDF. Much better tonal quality. I think the big difference is that MDF has so much glue in it. Much more mass and that acts like a solar heat sink holding in the resonance.. I think most speaker manufactures know that. But it does take a different and more expensive approach. You buy veneered plywood and build from that. With MDF you can build the speaker first and then if it is OK just cover with veneer. Not the degree of difficulty that working with expensive plywood has.
By the way what is french polish??? |
Since ply are veneered with birch I use veneer over the ply this sounds better than veneer faced ply. French polish is a hand applied shellac oil alcohol mix. Binds with veneer for best tone plus it looks great is easy to repair can last multiple lifetimes. |
JohnK
Are you a speaker manufacture or just a "crazy" audiophile like the rest of us?
That sounds like fun but a lot of work as well. Just curious how much the Birch ply costs per sheet and how hard is it to work with, doing the corners and miters etc. You purchase it with a finish veneer I suppose, walnut, cherry or what ever you want.
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I checked my old notes on birch plywood. One of the highest grades I have found is from a Finnish company called UPM. The standard UPM birch products come in 5x5 feet and 4x8 for product bonded with exterior grade glues. Price seems to be about $130 per sheet, but the importer (Plywood & Door) has a minimum of several sheets per order.
Max thickness for standard product is 1 and 1/8 inch with 22 plies per sheet.
I spoke to Rod at Plywood and Door
866. 738. 7265 |
Quido
Wow. That is so much more than mdf. The Finnish stuff I understand is the best. I would love to hear what some of the more expensive speakers would sound like if they were made from this stuff. That would be a project wouldn't it. Take a vanderstein and remake it in plywood. I am just a terrible woodworker so no chance here. |
The prices I mentioned are unit prices. . . I believe prices may go significantly down for quantity orders. |
Nanotubes. Haven't heard them yet though.
http://pubs.acs.org/doi/full/10.1021/nl802750z |
