RDO 198 and Monitor 10's
Comments
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Are those your reasons for championing MDF? LOL!Even baltic ply is subject to varying densities, core gaps, checking and cracking. Important things that one doesn't have to worry about with MDF.
Sounds like you're talking about shop grade ply. I'm talking about triple B or better for which these are non-issues. Now, what about the fact that MDF looks like sh$t, can't take a screw, is less rigid, dulls tools, is more easily damaged, and fu@ks up your lungs with formaldehyde in the dust?
Didn't rromeo923 have a problem with stripped screws? Oh the irony! -
Even baltic ply is subject to varying densities, core gaps, checking and cracking. Important things that one doesn't have to worry about with MDF.
I think what it boils down to is which one would look the best laminated with rosewood or walnut vinyl. LOL!Are those your reasons for championing MDF? LOL!
Sounds like you're talking about shop grade ply. I'm talking about triple B or better for which these are non-issues. Now, what about the fact that MDF looks like sh$t, can't take a screw, is less rigid, dulls tools, is more easily damaged, and fu@ks up your lungs with formaldehyde in the dust?
Didn't rromeo923 have a problem with stripped screws? Oh the irony!- SDA 2BTL · Sonicaps · Mills resistors · RDO-198s · New gaskets · H-nuts · Erse inductors · BH5 · Dynamat
- Crossover upgrades by westmassguy
- Marantz 1504 AVR (front speaker pre-outs to Adcom 555)
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- SDA 2BTL · Sonicaps · Mills resistors · RDO-198s · New gaskets · H-nuts · Erse inductors · BH5 · Dynamat
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Having used both in the creation of speaker cabinets I will say that MDF is more consistent especially in mutliple layers like those used in baffles but, I think Baltic Ply is far superior in the reproduction of lower frequencies in it doesn't color the sound as much as MDF can.
But I also think MDF is more forgiving (Sound Wise and Veneering wise) to the amateur DIY'er like myself.
But like JCandy said there are issues with using MDF. Easily Stripped, Bad to breath the dust from and is less rigid than ply on the whole.
All that said, I still use MDF more often than not.
I would also like to thank JCandy for the PDF he posted, Although it was republished in 2002 it is somewhat outdated as far as woods are concerned. MDF is much better than that now and there are several options that are not listed in that research, considering the newest reference in that text was from 1973, I hope you would agree. -
You make lots of good points. Let me just add that many top designers always use MDF and their experience base makes it so that there isn't much reason to change. They know joining and finishing tricks suited for MDF and the finished product is top-notch. In the commerical realm, because MDF is significantly cheaper than high-quality BB ply its the material of choice for mid-grade commercial speakers. Its not a quality issue, its a cost issue. You will, however, find ply used in high-cost speakers like Harbeth, Sonus Faber. It ain't cheap.All that said, I still use MDF more often than not.
Personally, I decided long ago not to use MDF simply for health/dust reasons. The use of real wood (remember, for the baffle, I use solid hardwood laminated onto plywood of equal or better thickness) just gives me a warm fuzzy feeling that MDF doesn't. -
Personally, I decided long ago not to use MDF simply for health/dust reasons. The use of real wood (remember, for the baffle, I use solid hardwood laminated onto plywood of equal or better thickness) just gives me a warm fuzzy feeling that MDF doesn't.
Nothing like that Warm Fuzzy feeling. :biggrin: -
MDF is a uniform known commodity whereas variables in natural wood cause sonic characteristics to vary species by species, and even tree by tree (of the same species). Manufacturers who use natural wood spend vast amounts of time learning/tuning what works properly.VTL ST50 w/mods / RCA6L6GC / TlfnknECC801S
Conrad Johnson PV-5 w/mods
TT Conrad Johnson Sonographe SG3 Oak / Sumiko LMT / Grado Woodbody Platinum / Sumiko PIB2 / The Clamp
Musical Fidelity A1 CDPro/ Bada DD-22 Tube CDP / Conrad Johnson SD-22 CDP
Tuners w/mods Kenwood KT5020 / Fisher KM60
MF x-DAC V8, HAInfo NG27
Herbies Ti-9 / Vibrapods / MIT Shotgun AC1 IEC's / MIT Shotgun 2 IC's / MIT Shotgun 2 Speaker Cables
PS Audio Cryo / PowerPort Premium Outlets / Exact Power EP15A Conditioner
Walnut SDA 2B TL /Oak SDA SRS II TL (Sonicaps/Mills/Cardas/Custom SDA ICs / Dynamat Extreme / Larry's Rings/ FSB-2 Spikes
NAD SS rigs w/mods
GIK panels -
We're talking about enclosures with 3/4" or better plywood and internal bracing, not a violin made from solid ebony. There is no tuning involved as the cabinet will be dead acoustically. One area where DIY absolutely shines above mid-grade speakers (like what you find at Best Buy) is the ease with which cabinet bracing can be applied. No choice of wood (MDF versus ply) can even begin to make up for improvements in cabinet rigidity obtained by even minimal bracing. Conversely, a large unbraced panel will contribute unwanted SPL no matter what wood its made from.inspiredsports wrote: »MDF is a uniform known commodity whereas variables in natural wood cause sonic characteristics to vary species by species, and even tree by tree (of the same species). Manufacturers who use natural wood spend vast amounts of time learning/tuning what works properly.
Finally, triple B (or better) Baltic birch ply is a known, standardized commodity.
The idea that MDF is superior in any significant way is a myth. -
Agreed ,with proper type and placement of bracing excellent results can be had with either MDF and void free baltic birch.I prefer working with MDF and use either full height dado'ed figure 8 or shelf type bracing that tie 4 panels together.Some such as George Short of NorthCreek use a mix of both MDF and BB in some of his cabinets. It may have been him that stated BB is a preferable bracing material because the multi direction plys will have greater resistance to flexure vs MDF. http://www.northcreekmusic.com/Pegasus/Pegasus.htmied. No choice of wood (MDF versus ply) can even begin to make up for improvements in cabinet rigidity obtained by even minimal bracing. Conversely, a large unbraced panel will contribute unwanted SPL no matter what wood its made from.
btw.Nice job on the Zaph MTM. -
Thanks. Actually, the photos show my own center-channel design, not the ZA5.3c center, even though there are numerous similarities. I probably introduced errors not in the proper Zaph design :redface:.btw.Nice job on the Zaph MTM.
Specifically, I optimized the design by knowing the seating position ahead of time and using that as the design axis. Also, the woofer spacing is closer to widen the central lobe, and the enclosure width narrower so as to improve the aesthetics as it sits under the HDTV. -
Thanks. Actually, the photos show my own center-channel design, not the ZA5.3c center, even though there are numerous similarities. I probably introduced errors not in the proper Zaph design :redface:.
Specifically, I optimized the design by knowing the seating position ahead of time and using that as the design axis. Also, the woofer spacing is closer to widen the central lobe, and the enclosure width narrower so as to improve the aesthetics as it sits under the HDTV.
I wish I would have taken a listen to your center channel! Looks awesome. -
Oops sorry for the assumption, he didn't do an MTM with the MCM woofers just the ZA14.(though they are essentially interchangabe).Thanks. Actually, the photos show my own center-channel design, not the ZA5.3c center, even though there are numerous similarities.
I found that the bracing technique I used for my MDF contructed CC resulted in a very inert cabinet.
http://www.polkaudio.com/forums/showthread.php?t=66967&highlight=active+3way+center -
Are those your reasons for championing MDF? LOL!
Sounds like you're talking about shop grade ply. I'm talking about triple B or better for which these are non-issues. Now, what about the fact that MDF looks like sh$t, can't take a screw, is less rigid, dulls tools, is more easily damaged, and fu@ks up your lungs with formaldehyde in the dust?
Didn't rromeo923 have a problem with stripped screws? Oh the irony!
Not my reasons, but the reasons of most speaker manufacturers.
1. MDF is covered with veneer, paint or other material, so your objection to the look is a non-factor.
2. Regardless of the material, the real solution is to use threaded metal inserts.
3. It's plenty rigid enough for the application. Another non-factor.
4. Yep, that'll happen to any tool one uses for cutting, routing, shaping, etc. Another non-factor.
5. BS. Another non-factor.
6. One should always wear a face mask or preferably a respirator when cutting, routing or sanding wooden materials. Another non-factor.
It appears that your main reason for using ply is its ability to hold a screw better than MDF. As I noted above in #2, the use of threaded metal inserts is far superior than any other method of attaching drivers, etc. Therefore, your reasoning is without merit.
A factor you seem to have overlooked is the use of dissimilar materials in the construction speaker cabinets is generally thought to be a no-no.
The true irony here is that you think you know what you're talking about, not unlike your thoughts on capacitors, sport.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
Not my reasons, but the reasons of most speaker manufacturers.
1. MDF is covered with veneer, paint or other material, so your objection to the look is a non-factor.
2. Regardless of the material, the real solution is to use threaded metal inserts.
3. It's plenty rigid enough for the application. Another non-factor.
4. Yep, that'll happen to any tool one uses for cutting, routing, shaping, etc. Another non-factor.
5. BS. Another non-factor.
6. One should always wear a face mask or preferably a respirator when cutting, routing or sanding wooden materials. Another non-factor.
It appears that your main reason for using ply is its ability to hold a screw better than MDF. As I noted above in #2, the use of threaded metal inserts is far superior than any other method of attaching drivers, etc. Therefore, your reasoning is without merit.
A factor you seem to have overlooked is the use of dissimilar materials in the construction speaker cabinets is generally thought to be a no-no.
The true irony here is that you think you know what you're talking about, not unlike your thoughts on capacitors, sport.
Dayum. :eek: -
1. That MDF needs to be covered with veneer or paint makes it better than ply, how?1. MDF is covered with veneer, paint or other material, so your objection to the look is a non-factor.
2. Regardless of the material, the real solution is to use threaded metal inserts.
3. It's plenty rigid enough for the application. Another non-factor.
4. Yep, that'll happen to any tool one uses for cutting, routing, shaping, etc. Another non-factor.
5. BS. Another non-factor.
6. One should always wear a face mask or preferably a respirator when cutting, routing or sanding wooden materials. Another non-factor.
2. The need to use inserts to hold a screw makes MDF better than ply, how?
3. Being less rigid makes it better than ply, how?
4. That MDF dulls tools makes it better than ply, how?
5. That MDF is more easily damaged than ply is a fact.
6. The formaldehyde-laced dust that gets stirred up by the kids after a project is done makes MFD better, how?
You're a riot!
Sport? Any time cowboy :cool:The true irony here is that you think you know what you're talking about, not unlike your thoughts on capacitors, sport. -
Impressive. That's a great illustration of a case where there is so much bracing that the cabinet resonance will be a non-issue. In commercial designs, cost makes this sort of bracing prohibitive, but the DIYer can brace the wholly jeezus out of an enclosure with minimal extra effort.I found that the bracing technique I used for my MDF contructed CC resulted in a very inert cabinet.
http://www.polkaudio.com/forums/showthread.php?t=66967&highlight=active+3way+center -
I'll probably have a pizza/beer/listening session in June. Other San Diego, Irvine, OC, LA, TJ lurkers would be welcome, too.audiocr381ve wrote: »I wish I would have taken a listen to your center channel! Looks awesome. -
News flash, you already lost this battle, just like you lost the cap battle. As a professional wood worker/finisher, it's obvious that you're just an amateur.
I'm your huckleberry, sport.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
I'll probably have a pizza/beer/listening session in June. Other San Diego, Irvine, OC, LA, TJ lurkers would be welcome, too.
I'm game. I've never been to a listening session, sounds fun! BTW, the 2B-"TL's" would be ready by then. Maybe I'll bring them along :cool:News flash, you already lost this battle, just like you lost the cap battle. As a professional wood worker/finisher, it's obvious that you're just an amateur.
I'm your huckleberry, sport.
Hahahaha! Dude, you're funny. -
When was it that you supported your original, bizarre assertion that "plywood, laminated or whatever is an extremely poor choice of any part of a speaker cabinet"? You can't win by running away, now can you?News flash, you already lost this battle, just like you lost the cap battle.
If you're a pro, it'll be a snap to support your claim that "plywood, laminated or whatever is an extremely poor choice of any part of a speaker cabinet". So far, all you've done is make excuses for shortcomings in MDF.As a professional wood worker/finisher, it's obvious that you're just an amateur.
Like I said, any time cowboy :cool:I'm your huckleberry, sport. -
1. I never run away.
2. I have supported my claim, your reading comprehension skills are lacking.
3. I'm always around.
BTW, that tiny RV fits you, sport.Political Correctness'.........defined
"A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."
President of Club Polk -
While I appreciate your willingness to educate me on the nuances of speaker box construction, I am well versed in general woodworking & finishing methods, having been a journeyman cabinet maker,finisher & shop foreman previously. One thing that bugs me a little is the seemingly interchangeability of the particle board and MDF names which are two very different and distinct materials. Furthermore, every Polk speaker cabinet that I possess is constructed with particle board. After having laminated and veneered several acres worth of various assemblies made of both MDF & P.board, I'd say that P'board is the more resonant of the two but...... has far superior gluing & screw holding characteristics. P.S. AFAIK, there never has been and most likely never will be a solid ebony violin, it's tough enough just finding small sections suitable for turning clarinet sections from, plus.......it'd prolly sound like ****!:biggrin:
My assortment:
SRSII p/bl, SDA-1A, SDA-2B p/bl (studio config.),Mon.10A, Mon.7B, Mon.5(forget which series) edit....My VM-20 is not of particle board:redface:
Solid wood alone is not a good idea for use as a baffle due to its propensity to change shape (split, crack, warp) over time. However, when laminated onto an equal or better thickness of plywood, the results are excellent. There is no need to veneer and, as you can see, large roundovers are possible.
The more prominent myth is that MDF is superior to birch plywood for building enclosures. Its just not true. Birch ply is actually stiffer than MDF (below, ModElas is modulus of elasticity).
18mm Birch ply:
ModElas = 3400 N/mm^2 (perp), 4600 N/mm^2 (parallel)
Density = 12.4 kg/m^2
18mm MDF:
ModElas = 2200 N/mm^2
Density = 10.8 kg/m^2
MDF dulls tools, its dust is very fine and contains formaldehyde, it hold screws poorly, corners are easily damaged, and there is no possibility to use it in an unfinished state because its so ugly. BB ply is beautiful (in my subjective opinion) with only a clear finish (shellac, acrylic or poly). -
I think what it boils down to is which one would look the best laminated with rosewood or walnut vinyl. LOL!
^^^^^^Funny as S-!t^^^^^^:biggrin: -
Plywood dulls tools far more than solid wood, and just about the same or a tiny bit less than MDF & P'board.
Plywood is typically laid up with a urea formaldehyde glue
Baltic birch is fine, if all you want is the boring-assed, non-grain look of birch.:frown:
ATB&R carbide tipped sawblades will cut a half pallet of ply, MDF or P'board before getting appreciably dull, are you running high speed steel by any chance?:eek: -
I'll probably have a pizza/beer/listening session in June. Other San Diego, Irvine, OC, LA, TJ lurkers would be welcome, too.
You gonna have a TJ sweetie do a donkey show also?? I'd fly over the fly-over states to see dat!!:eek::biggrin: -
Unless you laminate it like this.Baltic birch is fine, if all you want is the boring-assed, non-grain look of birch.:frown:
http://www.google.ca/imgres?imgurl=http://www.soundbysinger.com/UserFiles/Image/Magico%2520Mini%25202%2520Bracing.jpg&imgrefurl=http://www.soundbysinger.com/manf.php%3Fdoc_id%3D232&h=431&w=594&sz=23&tbnid=pYyF7IZp3L57tM:&tbnh=98&tbnw=135&prev=/search%3Fq%3Dmagico%2Bmini%26tbm%3Disch%26tbo%3Du&zoom=1&q=magico+mini&usg=__BFpT7CaF2lqQjRBgk5GB1SVuBbE=&sa=X&ei=vinPTay7NafX0QHI6cSWDg&ved=0CDYQ9QEwAw
The result is a very inert low colouration enclosure.
In fact on the DIY sites there are numerous examples of excellent laminated BB ply enclosures,most of which developed by highly accomplished designers.To say BB ply is unsuitable for use in loudspeaker enclosures is not factual. -
What's your point ? FYI, they are veneering the ply. While technically, veneering is a process of lamination, most people have Formica spring to mind when "laminate" is mentioned. I've done both, extensively.
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What's your point ?
It was in response to your " boring-assed " comment.My point being that IMO when laminated in that manner BB looks aesthetically quite appealing. -
Look again sport:biggrin:,it is a multi layering of vertically laminated pieces of BB not veneer.? FYI, they are veneering the ply.. -
Yes, because the birch is no longer evident.
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Look again sport:biggrin:,it is a multi layering of vertically laminate pieces of BB not veneer.
Don't pull that sport s@#t with me, for your effing information all plywood is laminated veneers of some sort or other. Upon closer inspection, I see that they've created butt ugly stacked layers of plys with a s@#tload of end grain showing, BFD, any buttcrack with a bandsaw and some bar clamps can do that.Please notice the top surface, boring assed birch,just like I said.
This discussion has been closed.