DIY Cab Advice...

[Zaphod B]

I don't understand why you need "the very best quality wood" for a guitar cabinet.. it really is un-necessary because the wood contributes very little to the sound, it's just a method of making the cabinet air-tight!!

Save the expensive wood for your guitars!!!

What you need for a guitar cab is a void-free, non-resonant wood and 13-ply baltic birch plywood is considered the best.

You can also make great cabs with MDF (medium-density fiberboard) although the woodworking purists turn up their noses at it.

The goal, though, is to make a cab that is strong, tight, non-resonant, and tough enough to withstand whatever road torture you plan on subjecting it to.

 

[travelin travis]

I don't think 'non-resonant' holds true with guitar cabs.

 

[Zaphod B]

I don't think 'non-resonant' holds true with guitar cabs.

"Resonant" and "rattling" are the same thing, just at different frequencies.

Particularly with a closed-back cab, any tendency of the cab to resonate translates directly into lost efficiency. I don't guess it matters so much with open-back designs.

 

[travelin travis]

'rattling' is when something is lose and being vibrated by resonation, such as a piece of hardware or piece of wood (void).

 

[Docaroo]

wow baltic birch plywood is cheaper than i thought it would be... looks like that could be the way??

Also what's the best material for the baffle? MDF?

 

[Zaphod B]

'rattling' is when something is lose and being vibrated by resonation, such as a piece of hardware or piece of wood (void).

I know, I know. Just tryin' to make a funny.

I've been admonished before that guitar speaker cabs are not the same as hi-fi speakers, and that's true for lots of reasons. But one of the cardinal rules of high-fidelity speaker design is that the enclosure must be as resonant-free as possible, and that any potential resonant modes should be broken up by non-symmetrical bracing and other techniques.

The whole point is that the only thing vibrating should be your speaker. If anything else is vibrating, it is by definition non-musical and indicates that some of the speaker's energy is serving a purpose other than moving air off the cone.

 

[Zaphod B]

wow baltic birch plywood is cheaper than i thought it would be... looks like that could be the way??

Also what's the best material for the baffle? MDF?

Use the same material for both.

 

[Lt. Bob]

for a very cool covering a friend of mine used that roll on pickup truck bed liner. He put it on about 1/4" thick ...... looks great and it's impervious to most anything and if it does get nicked you just put some more on.

 

[travelin travis]

I know, I know. Just tryin' to make a funny.

I've been admonished before that guitar speaker cabs are not the same as hi-fi speakers, and that's true for lots of reasons. But one of the cardinal rules of high-fidelity speaker design is that the enclosure must be as resonant-free as possible, and that any potential resonant modes should be broken up by non-symmetrical bracing and other techniques.

That's not true for guitar cabinets. Guitar and hifi are only cousins.

 

[Zaphod B]

That's not true for guitar cabinets. Guitar and hifi are only cousins.

I think this is where I'm supposed to tell you to kiss my ass.

.

 

[travelin travis]

Seriously, think about it. One of the best sounding amps ever made, the tweed bassman, used a thin speaker baffle which in the hi fi world is a big no no.

Also, guitar amps are ridden with distortion........and the non linear speakers...............

 

[DogFood]

Hats off to anyone who wants to create, wood or noise or any point in between. Some thoughts...

Series circuits resistance is additive, easy, R1+R2+R3+R4=Rtotal

(note: I don't know where the omega/resistance ohms symbol is on this keyboard)

Parallel circuits (omg such a beeeeeg secret!) resistance is figured with this formula....

__________________________1__________________________
__1___ + ____1____ + ____1_____ + _____1____
....R1............. R2..............R3.................R4

for all you english majors out there it is: one divided by one divided by resistance one plus one divided by resistance two plus etc.

and combo circuits are figured out with parallel first then series.

gotta cut this one short, the little lady is waiting....later

 

[Track Rat]

Yep. The reciprocal method.

 

[NRS]

Seriously, think about it. One of the best sounding amps ever made, the tweed bassman, used a thin speaker baffle which in the hi fi world is a big no no.

Also, guitar amps are ridden with distortion........and the non linear speakers...............

The problem with deliberately trying to build any thin baffle cab that resonates like that is the cab itself ends up throwing out a certian frequency of its own that may not agree with your speakers. Although it is possible this frequency could add improvement to your sound, theres really no audio science I'm aware of on predicting what that frequency will be or how to tune it (unlike port design). I've built cheap quicky temporary guitar cabs like that before and can say the more solid ones with the same speakers were easier to EQ and sounded better.

 

[travelin travis]

I wouldn't mind building a cab and experiementing with various baffle thickness's and speaker combinations. I'm sure there are some interesting combinations to be found.

 

[Docaroo]

should i keep my cabs closed or use a port? would there be any real benefit to a port on a guitar cab??

btw... design coming along well! just thinking things through atm

 

[NRS]

If your going for deliberate cabinet resonence, then even more interesting may be the introduction of various furniture grade hardwoods such as solid maple, oak or mohogany instead of plywood. Then your bringing those woods different tones into play. Probably wouldnt be cheap though.

 

[travelin travis]

should i keep my cabs closed or use a port? would there be any real benefit to a port on a guitar cab??

btw... design coming along well! just thinking things through atm

if i were to build a cab, i think i'd go with a convertible back.

 

[NRS]

should i keep my cabs closed or use a port? would there be any real benefit to a port on a guitar cab??

btw... design coming along well! just thinking things through atm

Depends if you feel your getting enough bottom end out of your cab when its done as ports are typically meant to extend your low end frequncy response. Most guitar cabs dont have em as Guitar is more a midrange instrument that you wouldnt want too much bottom end out of anyway if you expect to contrast the bassist nicely in the mix. Most guitar speakes by themself in a closed box have adequite bottom end but I could see a player who uses a seven string or heavy drop tuning wanting some extra low end oomph. Just the opposite is an open back like on most combos. Sounds a bit thinner but much more open sounding and spacial dispersion throughout the room.

 

[Track Rat]

if i were to build a cab, i think i'd go with a convertible back.

Bulls eye. You could go back and forth between open back and infinate baffle. Very cool.