Assuming you're referring to panel goods .... Rona has a 'shop' birch plywood measuring 11/16" thick and which has 7 layers, not counting the face veneers, for a paltry $65 (Cdn). Yes, it has a few voids, and the occasional blemish on the face veneers, but for that $$ it's a good buy.
My apology, I should have mentioned the dimensions. Yes, that's for a 4' x 8' sheet.
It is not so much the material as knowing how to use it. Fret over your crossovers, not the plywood.
MDF, even the junk from big-box stores can work very well. Particle Board was SOP for 50 years with no complaints. Quality MDF as cabinet makers use is better as it is flatter and does not de-laminate as much. Then there is HDF which machines super well and is still a bit "dead". But for smaller cabinets, I am going back to Birch ply. Again, not the junk from the Home Despot suppliers, but true cabinet grade. My subs I just use 3/4 ply construction grade as I can lift the result. Sobs should not have issues with high frequency resonances anyway. A friend built a series commercially using 1/8 Masonite with an internal grid. Worked great but was too labor intensive. Made the cabinets smaller which was a marketing goal and the grid scattered the woofer back wave.
Marine ply will be certified as void free and the glue waterproof, not water resistant. No magic. You can get very nice ply from home-built aircraft suppliers too, but again, paying for certification.
I was not happy, the last sheets of birch ply I got from The Hardwood Store had a few voids. It should not. Cabinet wood suppliers also have other plywood's stiffer than birch.
MDF is no more nasty to deal with than any wood. All woodworking should be done with a respirator. Sawdust will kill you.
MDF, even the junk from big-box stores can work very well. Particle Board was SOP for 50 years with no complaints. Quality MDF as cabinet makers use is better as it is flatter and does not de-laminate as much. Then there is HDF which machines super well and is still a bit "dead". But for smaller cabinets, I am going back to Birch ply. Again, not the junk from the Home Despot suppliers, but true cabinet grade. My subs I just use 3/4 ply construction grade as I can lift the result. Sobs should not have issues with high frequency resonances anyway. A friend built a series commercially using 1/8 Masonite with an internal grid. Worked great but was too labor intensive. Made the cabinets smaller which was a marketing goal and the grid scattered the woofer back wave.
Marine ply will be certified as void free and the glue waterproof, not water resistant. No magic. You can get very nice ply from home-built aircraft suppliers too, but again, paying for certification.
I was not happy, the last sheets of birch ply I got from The Hardwood Store had a few voids. It should not. Cabinet wood suppliers also have other plywood's stiffer than birch.
MDF is no more nasty to deal with than any wood. All woodworking should be done with a respirator. Sawdust will kill you.
I prefer ply over mdf. This veneered ply was meant for open some open baffles. I changed direction to a flexy rack x 8 shelves. The shelf I need more atm.
I also made my Thoren's 160 base cover with marine grade ply, 1/4" Many guys prefer MDF for this application. I can't say which sounds best, but mine beats the the original inferior part.
I also made my Thoren's 160 base cover with marine grade ply, 1/4" Many guys prefer MDF for this application. I can't say which sounds best, but mine beats the the original inferior part.
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Plywood is better for any speaker that gets moved, such as a Portable PA speaker because Plywood is light and Strong. MDF is better for anything you will be routing as it is a more homogeneous material that will allow you to recess drivers, round edges etc. MDF is also less resonant than Plywood which makes it better for Audiophile speakers. The penalty with MDF is weight and fragility. MDF could potentially also be more toxic but you do not want to breathe the dust from either MDF or Plywood. Both are good materials for speakers but they do have differences.
That argument holds no water.
Everything resonates. MDF typically resonantes at lower frequencies with broader Q, more likely to be excited than the same thickness of quality plywood. 15mm ply can be made to outperform ¾” MDF which gives the equal thickness ply an even bigger edge.
dave
yeah that was a bit of a generalization on my part ...
it will come down to details such as dimensions, frequencies and bracing ...
i think in general DIYers focus on sound while OEMs focus on more practical considerations such as cost, durability, available finishes etc ...
of course in their marketing documents OEMs will talk about sound but that's not what they have on their mind for the most part ...
gullible consumers take it at face value of course and then they begin to think that a speaker MUST be made out of MDF to sound good or that a speaker cable MUST be made out of silver ...
but in the end it's just about proper design, not material choice ...
MDF is not as durable, but its only real use, IMO, is that it is cheap. Cheaper to buy, cheaper to machine, cheaper to finish, not as cheap to ship.
dave
dave
I finished the flexy. If I made it out of MDF I'd still be picking sawdust out of everywhere. Besides the shelves would start to sag by having a 50-60 lb amplifier on it. The ply feels as stable as can be.
I already got another plywood project lined up.
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Also it is used because it is has good mechanical damping(*) and is more consistent in properties than natural wood (although quality plywood should be pretty consistent too as the layers average out).
(*) it doesn't make good zylophone bars 🙂
Each has its pluses in different areas. For things like speaker enclosures, I can live with witchever sounds best, as long as its being veneered. And someone else went through the trouble of building it 😉 Finishing MDF unless its veneered and the sub base is completely covered. Its not worth the trouble.
Here is a decent read https://www.paradeofhomes.org/blog/mdf-solid-wood-furniture-advantages-disadvantages/
https://georgehill-timber.co.uk/blo...ges of MDF,router to create decorative edges.
Here is a decent read https://www.paradeofhomes.org/blog/mdf-solid-wood-furniture-advantages-disadvantages/
https://georgehill-timber.co.uk/blo...ges of MDF,router to create decorative edges.
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consistency is probably a huge factor for large commercial operations. guys like us can look at every sheet of plywood individually to examine it for straightness then we can slightly change our approach for pieces that may not be perfectly straight - put a few extra clamps here and there for example.
a big company has to just be able to throw a sheet into some computerized machine without anybody having to waste even a minute looking at it ...
well you can just paint the MDF enclosure ...
i think one benefit of Plywood for DIY is that if you leave exposed plywood edges ( lacquered ) then your box is instantly recognizable as something you built yourself ...
because even though all high end prosound speakers are made of plywood it's always painted black while all the high end home and studio speakers are made of MDF ...
only DIY speakers are ever made with exposed plywood so if you want everybody to know you built your speakers yourself that may be a consideration ...
You can paint it. But the end cuts of MDF aren't as pretty when they absorb paints like a sponge and create dull spots. Similar when you fill in screw holes with some type of plastic wood. When light reflects it always seems to make those little spots more obvious when they show through the finish.
I like how the edges look and show the ply lines. In the past I would iron on a wood veneer edge to hide it. Some builders are skilled at showing off of the ply lines.
I quite like the layered plywood look once its cleared.
I think I will build a second rack with genuine Baltic Birch. I ran out. The top tiers are Baltic Birch you can see how much nicer and consistent the ply layers are in my image. Its stronger, and is said to have better acoustic properties.
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Years ago I built a pair of full range vented enclosure bookshelf speakers out of 20mm thick Pine with 6mm thick MDF adhered to the inside, solid as…
I’ve just started on another set using Oak, I was very happy with the original set so plan to use the same MDF lining. I use Titebond wood adhesive to bond the layers together.
Unless you are painting, I think solid timber is easier to get joins looking nice, I’ve tried timber laminates but never enjoyed working with them.
I’ve just started on another set using Oak, I was very happy with the original set so plan to use the same MDF lining. I use Titebond wood adhesive to bond the layers together.
Unless you are painting, I think solid timber is easier to get joins looking nice, I’ve tried timber laminates but never enjoyed working with them.
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Liking plywood, will probably like my turntable build then.
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Awesome, Baltic Birch plywood plinths not only look great and to have so much going on, the options for them seems almost unlimited. Then theres also the acoustic values.
Thats a match made in audio heaven. The base I did for the Thoren's, the end game involves a 8 or 10 inch BB plinth. My analog stuff has to remain on a shelf so I can focus on speakers and inside the digital domain for a while.
P.S I can hardly wait to clear coat other stands I'm in the middle of making. I tripled up on 3/4" sheet.
When the clear accentuates the end plies, seeing how they turn out in finish is one of my favorite stages.
That was a piece from a boat cubby, so even less than perfect. I prefer recycling timber whenever I can. The age and wear just gave it more character. MDF might of disintegrated by now.
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