Ply or real wood for speaker cabs?

[Aurora]

Hi guys....
What's your sincere opinions the choice of ply or real wood for speaker and combo cabs?
Is there 'really' any difference to speak of?
( Not counting hardwoods for looks)

[ampdoc1]

Aurora,

Probably due to high cost, and the sizes required, I don't think any professional speaker manufacturers (the big well known companies, not to demean other builders), that use anything but plywood. 12 ply Baltic Birch is the most common.

ampdoc1

[Aurora]

Well- somehow I know that, but I was more sort of looking for the truth about the "cab mojo" in real wood.
Since I come from an engineering background, I sometimes find it hard to sort the truths from the myths......

[Andy Le Blanc]

Its more along the lines of whether or not you want the cab to color your tone.
Mdf and plywood are fine, but pine is light weight and a bit resonant, it reacts.
I mad a solid oak cab and baffle once, sounds great, looks good, and is lighter
than mdf. Wood cabs seem a bit more live, usually for audio you want the
cab to be very stiff and not contribute adversely to sound reproduction, but
with electric guitar the amp and speaker are half the instrument and fidelity
takes a back seat to how the box couples to the room. Wood interacts with
the system and room where plywood and mdf isolate the speaker a little
more.

[dave g]

Personally I like 12 ply baltic birch. I have done hardwood speaker cabinets before, and though they look nice they're more expensive and less durable. There is definitely a noticeable difference in sound - in general, I usually prefer the way that the plywood cabs sound. That being said, my own personal go-to cabinet is an oval ported african mahogany 1x12" loaded with a G12-65 because it just happened to sound so spectacular.

[Kregg]

I was once told "if you want that Fender mojo use clear pine." In looking at older Fender tweeds I noticed random dark stains coming through the tweed, they were fact made with knotty pine. I wouldn't use knotty pine because knots can loosen up and fall out. If you use 5/8" or 3/4" ply for the box go with voidless birch or a better grade of pine ply. I was looking at the coloration of an old Ampeg, which may have been cedar ply, either that or they stained the wood, which seems unlikely.
The most important aspect of a great box are good tight joints. I prefer finger (box) joints or dovetails.
Baffle thickness from 1/4" to 3/4" varies depending on the speakers and the span of the baffle. If I use 12" -15" speakers 5/8" is the thinest ply I'd use for a guitar cabinet; I wouldn't use anything less than 3/4" for a bass cabinet.
For an isolation box or audio speakers I'd use MDF. But, for traveling I'd avoid MDF due to it's weight.
At any rate, play around with various materials, who knows, maybe you'll come up with an amp with your very own brand of mojo.

[Structo]

For small combos pine is the one that keeps getting mentioned but it seems hard to find any clear pine anymore.
At least around my neck of the woods.

Having spent time at some Hi Fi forums a few years ago, a lot of those guys say MDF is the perfect cab wood for it's neutralness and lack of resonance.

But it would be heavy as hell if the cab is of any size.

Seems like most custom cab companies use the voidless birch ply for quality cabs.

[Sonny ReVerb]

I've been thinking of building a cab for a Jensen C12PS I pulled from an old organ. I'd like to do a pine cab, but one of the problems I've found is that you're limited to standard board widths. I'd like to make the depth of the cab around 14", but the widest boards in the hardware store are 12" (actually 11 1/2"). It seems that if you make a panel by joining two pieces lengthwise, you'd lose the benefit (resonance) of the pine. I guess you could make a 13" deep cab if you include the front and back panels.

[fperron_kt88]

Don't know if this helps, but here are my findings:

Bought a custom slanted 4x12 cab years ago (of the lowest imaginable quality...), slightly smaller than a regular slanted marshall (the depth of the cab was the same as the depth of a regular Marshall 50W JCM-800 head). Was made of run of the mill 3/4" plywood as commonly available in 4'x8' for flooring construction work (am in canada). So not birch.

Using the same speakers and hardware (handles, corners, castors) this cab was completly rebuilt into a real dimension marshall slanted 4x12. This time using the 5/8" thick birch ply.

Night and day. Of course the internal volume probably doubled in the process, but the tightness and presence was greatly improved.

A few lessons learned in the process:

*2 variables were changed: int. volume and materials so I cannot conclude on the importance of either, but the result was completely astounding. The prop was bland, loose in the bottom and the birch-ply was lively and punchy.

*I played with the materials of the back: the reference model 4x12 I had in the shop had a particle board. So I swapped between particle board back and birch-ply back. The particle was much looser and grittier where the birch ply was much cleaner and punchier. Marshall major amp and G12T75s, ran the cabs in parallel, then one after the other in as-quick-as-I-could-without-damaging-the-amp A/B test.

*BTW, birch ply is available in 5'x5' panels instead of 4'x8'. I had a blast realising that the current design of a marshall 4x12 fits in one panel (except for the back to front baffle connection strut, which is a piece of 2x3 or similar, as I recall). I strongly believe that this specific design was established as to maximize the internal volume of the enclosure while minimizing wood loss !!! If somebody in 1964 would have asked: "Here are four 12" inch speakers and your task is to build the largest enclosure to contain them with this piece of 5'x5' baltic birch plywood." the answer would certainly have been the marshall bottom cab design. Quite funny no?

I had an eye on MDF at first. Turned out that working with birch ply is much easier on everything (blades, routing, dust). Then the weight... Just for that, I would stick with birch ply.

[Kregg]

Nicely put fperron_kt88.

For a primer the current issue of Vintage Guitar has an article on building an amp cabinet.
Also, this site has a great photo documented build, as well as pdf cabinet plans. http://www.silvatone.bravepages.com/

[Structo]

Nicely put fperron_kt88.

The current issue of Vintage Guitar has an article on building an amp cabinet.

Dang it!

Wouldn't you know it, I let that subscription expire......

[jaysg]

I went down a path that yeilded a poor match. I replaced an MDF combo cab with a home depot #2 pine cab. I recently talked to the guy who spec'd the speaker and the bottom line is, the replacement isn't heavy enough for the Greenback clone. Lighter weight had been my cunning plan. Sigh.

My options are to try other speakers or rebuild a heavier cabinet. I'm thinking poplar, which I've used successfully in the past.

There's a recent thread about Dumble cabinets. Apparently, he's made some from heavier marine-grade plywood, not baltic birch and doesn't like BB. Go figure.

I'd like to say, 'hope that helps,' but it doesn't.

[M Fowler]

Nothing wrong with building your own cabs and I do as well but you can pickup used Peavey for $200 to $250 and even a new Fender FM 4x12 for $320 or less. Sell the speakers or use them for PA or monitor cabs as I have, matched with one nice Eminence in each PA column. You get a good overall frequency range that way.

The point is the Peavey cab and Fender cabs are high quality wood construction not MFD and very reasonably priced, just add speaker of choice.

But I do enjoy building cabs.

Mark

[Kregg]

With all this 412 cabinet talk, does anybody out there have a resource on cabinet plans for a 412 slant?

[fperron_kt88]

Search for .pdf in this page: http://www.thefret.net/showthread.php?t=4873