Foam/filling inside of cabs??

I've met a few people on here who stuff there 4x12's with either some kind of isolation foam or padding, and vouch that it sounds really, really good. I always thought that the extra room in a 4x12 is what made it sound big and thunderous. Maybe I was wrong.....

Has anyone else tried this? I am always up for easy, inexpensive ways to improve tone! If anything, I can try gluing some padding to the inside walls of the cab, but don't want to do anything real extensive that I can't reverse.

Thanks!

I put a piece of carpet padding on the back wall of my 4x12's ...... It was so long ago I can not remember how it effected the sound. But I decide to leave it in there.

Has anyone else done this, and what result did you get?

I too have heard of people doing this, but I haven't gotten any substantial opinion... and am to lazy to open my cab unless there is gain

The use of damping material is common among Hi Fi speakers. It reduces sound wave reflections inside the cabinet,
(and reduces the effect of resonance of the cabinet).
These reflections can (depending on the dimensions of the enclosure) end up causing some phase cancellation of certain frequencies while accentuating others (generally affecting lower frequencies). You can use foam rubber or fiberglass (similar to fiberglass insulation; sold at Radio Shack). It will almost always make an audible difference depending how much you use (you may need to use quite a lot to really make a difference) and it's position in the cabinet. Whether it will make a guitar cab "sound better" is a matter of trying and judging for yourself.

I have some foam in my 1 x 12 cabs, nothing in my 4 x 12 and they all sound good anyway. :roll:

There is a lot of info on this on the 'net under Hi Fi and stereo topics. Google it and see!

you know, good cabinets are designed with dimensions and material to actually use the reflective sounds to the benefit of the overall 'tone' and signature of the cabinet....


why would you want to kill that?


otherwise, why not just build a cabinet out of concrete?
or lead?

gonzo said:

otherwise, why not just build a cabinet out of concrete?
or lead?

Click to expand...

Or other types of HEAVY METAL!!! \m/ :twisted: \m/

If you have a ported cab, I would think any sound deadening insulation would screw up the reflected wave function of the cab.

gonzo said:

otherwise, why not just build a cabinet out of concrete?
or lead?

Click to expand...

Because 4 12L's is already too **** heavy

about Gonzo's post, a good one IMO...

Don't forget that even a tolex covering greatly damps those cab reasonances. The type of wood used has some tonal effect in a cab too, more so with the naked ones. Curt Emery, builder of the popular boutique amps Superbaby and Microbaby builds naked cabs out of Mahogany, gorgeous to look at and great sounding.

gonzo said:

otherwise, why not just build a cabinet out of concrete?
or lead?

Click to expand...

And now time for that famous game show....
CAN O' WORMS!! :lol: :lol:

Aww, just being humorous here, but actually a collaboration of speaker designers/manufacturers did exactly that back in the sixties!
IMF (aka Fried) KEF, and Kelly speaker companies actually built bass horns using concrete to avoid the effects of standard materials (ie wood) absorbing sonic energy inside the cabinets. This lead to the search for higher density materials in cabinet design. Concrete was way too heavy (though sonically superior) so now many HiFi speakers/subwoofer makers use MDF (medium density fiberboard) as it offers much of the benefit at a fraction of the weight.
So......it's been done! :wink:

I do agree that when it comes to guitar tone the rules for HiFi will not always apply. We often want the cabinet to color the sound, because it rocks! :lol:

I've tried that in the past, in an attempt to "improve" a cabs sound. The result was a flat and far less responsive cab that was devoid of any dimension and depth. I think someone has already pointed out that if your cab is ported in any way, and 2 of mine are, you'll lose the reason you bought it for. Perhaps an alternative would be to play with the port size or, in the case of Genz Benz cabs, plug some of the front ports. Beam Blockers as well, not to intentionally endorse, could help in subduing some of those ice-pick highs that might be driving you to want to put foam inside in the first place.

Old BF Shred said:

gonzo said:

otherwise, why not just build a cabinet out of concrete?
or lead?

Click to expand...

And now time for that famous game show....
CAN O' WORMS!! :lol: :lol:

Aww, just being humorous here, but actually a collaboration of speaker designers/manufacturers did exactly that back in the sixties!
IMF (aka Fried) KEF, and Kelly speaker companies actually built bass horns using concrete to avoid the effects of standard materials (ie wood) absorbing sonic energy inside the cabinets. This lead to the search for higher density materials in cabinet design. Concrete was way too heavy (though sonically superior) so now many HiFi speakers/subwoofer makers use MDF (medium density fiberboard) as it offers much of the benefit at a fraction of the weight.
So......it's been done! :wink:

I do agree that when it comes to guitar tone the rules for HiFi will not always apply. We often want the cabinet to color the sound, because it rocks! :lol:

Click to expand...

It's funny that you mention this as many high-end subwoofers for AV have granite or marble bases the help deaden the sound as well as reduce transference.

Yea, and talk about a "ton of tone", eh? :lol:

Heritage Softail said:

If you have a ported cab, I would think any sound deadening insulation would screw up the reflected wave function of the cab.

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The EV Thiele 1 x 12 ported cabinet plans (from the manufacturer) call for lining cabinet with insulation.


See #11 in the "construction notes:"
http://hf-antenna.com/Flotsam/EV/ElectroVoice_TL806.pdf

I received a copy of these plans from EV back in the early 1990s and built a cabinet (that I still have), lined it with insulation and loaded it with a EVM12L--sounds awesome. I later purchased a Mesa Boogie 1 x 12 Thiele cab that was loaded with a EVM 12L--it did not have the insulation that EV calls for in their own plans so I opened it up and lined it--it was a nice improvement.

YEA, the idea of HI FI is kinda counter to a rock and roll cabinet.

gonzo said:

YEA, the idea of HI FI is kinda counter to a rock and roll cabinet.

Click to expand...

So, are you saying that Hi Fi versus a guitar cab should or shouldn't have insulation in it? I think it really depends on what you are trying to achieve and the design of cabinet , closed, ported etc. The EV cab and speaker referenced in the previous post is specifically a guitar speaker and cab. The manufacturer calls for insulation inside the cab. The very same cab (which was often also loaded with and EVM12L) as sold by Mesa Boogie, did not have the lining inside it, at least the one I had didn't. I put insulation in mine and thought it was an improvement.