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Topic: Speaker box materials? |
Archie Cox
From:
Austin, Texas, USA
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Posted 23 Jan 2001 11:43 pm |
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| Is there any difference in the performance of a speaker based on the materials which the speakers enclosure is made of? For instance, is a particle board baffle superior to a plywood baffle? I am particularly interested the difference a solid wood enclosure makes in the tone of a speaker. |
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Dave Boothroyd
From:
Staffordshire Moorlands
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Posted 24 Jan 2001 12:44 am
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The best sounding speakers we have in our studios have cabinets made of cast steel!
Mind you, they are studio monitors where the idea is that the frequency response should be absolutely even. Accordingly the cabinets are made so they will not resonate at any frequency that even bats might hear.
If you consider the side of a speaker cab to be a flat panel suported at its edges, the resonant frequency is related to the stiffness, area and density of the panel material. Particle board is good in that its stiffness and density are uniform, so you can engineer the resonant frequency to suit your ears. Wood has differing stiffness along and across the grain, so will probably not just have one simple resonant frequency. That may or may not sound better! Of course the space inside the cabinet resonates too and just to make a complex situation worse- there are often damping materials or resonant tubes or ports inside the cabinet which affect the resonance. If your cabs resonate at audio freqencies, some parts (harmonics) of your sound will be transmitted better than others. If they are the harmonics you like to hear, fine. If they are not, it will sound bad!
To sum up- sorry mate, without a lot of maths I have no idea!
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Cheers!
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Jack Stoner
From:
Kansas City, MO
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Posted 24 Jan 2001 3:36 am
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I've read articles that say the denser wood materials, e.g. cabinet makers grade of particle board (not the crap you buy at Home Depot, etc) is the best. However, I look at some of the commerical stuff and although there is a lot of (cheap grade)particle board, there are enclosures of plywood and "real" wood.
One JBL speaker book I read made the point of having the cabinet rigid and of adding braces to the pieces to fortify cabinet material. One suggestion in that JBL book was to take the speaker cutout from the baffle board and mount it to the bottom of the cabinet to increase stability.
There are a lot of different "schools of thought" on speaker construction. The application and type of enclosure probably is a factor in selecting the cabinet material. e.g. open back speaker cabinets probably are not as critical as closed cabinets.
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Rick Johnson
From:
Wheelwright, Ky USA
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Posted 24 Jan 2001 5:29 am
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I build a lot of replica cabs. I use pine with the fingerjoint. On baffles I use
1/2 birch plywood. Pine resonates very nice
and the birch is stronger and more durable than particle board and paints up nice.
Lots of guys use plywood on the cabs and
plug them with dowels for strength. They do this to speed up production. The fingerjoint
is the best in my book.
Rick
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Rick Johnson |
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Joe E
From:
Houston Texas
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Posted 24 Jan 2001 12:45 pm
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I guess I'll add my 2 pennies.
The harder or more dense the wood the more harsh the sound. Also the more sound material you need to add to the inside to deaden the sound.
So the opposite also applies. As you use softer woods the tone becomes more mellow until it becomes mush.
Most top grade builders these days use a multi-ply birch. Usually 7 layers. Birch is not that dense of wood. So it has a warm sound. The grains in the multiple layers are stagered in alternating directions. This helps eliminate alot of the resonances. As the sound passes through it reflects differently on each layer and thus reducing the resonance quickly.
Altimately though the "design" will have the biggest influences on the sound. Especially in closed/ported cabinets. An open back cabinet has very little to do with the sound but a closed box does.
The cabinet is tuned to a frequency that is best suited for the speaker/cabinet combonation. As you tune the cabinet by opening or closing the size of the port the frequency response becomes flatter or more peaked depending on direction.
Also you may want to stay away from cabinets that are tuned for certain frequencies that could play havack on specific instruments sounds. EX: if the cab is tuned at 100 hz this could be a tough freqency for a bass guitar to EQ around to get a good sound.
Hope this helps[This message was edited by Joe E on 24 January 2001 at 12:49 PM.] [This message was edited by Joe E on 24 January 2001 at 12:50 PM.] |
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Jim Palenscar
From:
Oceanside, Calif, USA
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Posted 24 Jan 2001 5:09 pm
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| After doing a bit of research on the issue I recently chose 3/4" 13 ply Apple/Birch for my latest speaker enclosures available from a local hardwood store. It is quite heavy but I was enclosing 12" speakers (moving smaller from 15's)- too bad the cabinets were not lighter but I am very happy with the results. |
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Ole Dantoft
From:
Copenhagen, Denmark
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Posted 25 Jan 2001 1:10 am
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Archie,
I guess to sum up all of this you could say, that the thicker and denser the wood (or other material), the less the cabinet itself will have to do with the sound ! This probably applies mostly to CLOSED cabinets though.
But consider also, that the 59 Fender Bassman 4x10 is considered among many guitarists to be the ultimate guitar tone-machine, and it's made out of relatively thin, solid pine and furthermore the baffle is "float-mounted" i.e. it's only held in place by screws at the to and bottom edges, with no support down the sides !!
Just my .02 $
Ole
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Jack Stoner
From:
Kansas City, MO
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Posted 25 Jan 2001 4:38 am
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Ole is right. Along with all the technical specs, etc. If you look at a lot of great sounding commercial built speakers or combo amps they defy all the enclosure design principals.
I have a pair of speakers on my home stereo system that were built using JBL speaker enclosure specs, including lining the inside with fiberglass insulation, etc. Each one has a JBL D-120F (from an AB768 Fender Twin) and a tweeter. They work fantastic. I also have a pair of Peavey Nashville 112E clone enclosures that I built using Home Depot grade plywood and I've got positive comments from everyone on how they sound. Go figure. |
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Ricky Davis
From:
Bertram, Texas USA
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Posted 25 Jan 2001 11:03 am
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My suggestion would be the Pine box(either doweled or fingerjointed)with a Birch baffle board screwed in. Open back is prefered by folks that play on a stage and you toss a nice old D-130 in there and your good to go. You won't find a better sounding speaker box than that pal.
Ricky |
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Bob Hoffnar
From:
Austin, Tx
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Posted 25 Jan 2001 11:54 pm
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What does Duane Marrs build his cabs out of ? They are small, hardly weigh anything and they sound amazing.
Bob
Archie, It looks like somebody screwed up and is going to fly me to SxSW. I owe you a beer at Ginny's ! [This message was edited by Bob Hoffnar on 25 January 2001 at 11:58 PM.] [This message was edited by Bob Hoffnar on 26 January 2001 at 12:04 AM.] |
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norm mcdaniel
From:
waco tx
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Posted 27 Jan 2001 7:27 am
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| ive been building cabs for a while and use cabinet grade burch plywood. i make the baffel board out of the same material. so far they sound great. ive covered them in black duratuff and some black tolex material like some amp companies use. i also made a set for bob lee in california for twelve in speakers, you might ask him how he likes them. they have half way open backs. |
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