Cabinets: Front loaded vs. rear loaded

[Craig S]

Does one project or disperse sound better that the other?

[guitfiddler]

Front loaded is slightly better, especially if your mounting board is 3/4" thick or so. It's also better in a cabinet where the mounting board is deeper set. You want to avoid deflection of sound waves by the edges of the cab. This is why home audio spkr. systems always use front-loaded drivers, and the cabinet edges are flush with or slightly behind the front surface of the drivers.

That said, guitar & bass cab's. typically use rear-loaded speakers because the front panels & grill cloth often are not readily removeable, and it's just as easy to pop the back of the cab. off to get at the spkrs.

And, in a live band situation, you're never going to be able to hear the difference.

[Guest Mike Lee]

I prefer rear loaded, mostly because guitar speakers come with a foam gasket that looks pretty stupid out front. Rear loading can enhance bass, especially when using an "acoustic lens", which is basically a spacer that increases the effective depth of the baffle. It's an old PA trick that Dr. Z uses on his amps and cabs to good effect.

[Luke]

Front loaded is slightly better,

And, in a live band situation, you're never going to be able to hear the difference.

I could not disagree more strongly on either point, and the millions of Marshall 4x12s that are rear mounted would attest this fact.

[Scottcrud]

Front loaded is slightly better,

And, in a live band situation, you're never going to be able to hear the difference.

I could not disagree more strongly on either point, and the millions of Marshall 4x12s that are rear mounted would attest this fact.

What about the millions of Boogie cabs that are front loaded? And built WAAAAYYY better than a Marshall cabinet? In the end it's a very subjective question, some may like one or the other, but is one way really better than the other?

[MCChris]

I have a front-loaded 4x12 and a couple rear-loaded 2x12s, but there are so many variables between them in terms of speaker type and cabinet construction that describing the difference between the two methods of speaker mounting would be impossible. Only way to really do that would be to A/B cabs that are identical except for how the speakers are loaded.

[JohnnyB]

... You want to avoid deflection of sound waves by the edges of the cab. This is why home audio spkr. systems always use front-loaded drivers, and the cabinet edges are flush with or slightly behind the front surface of the drivers.

That said, guitar & bass cab's. typically use rear-loaded speakers because the front panels & grill cloth often are not readily removeable, and it's just as easy to pop the back of the cab. off to get at the spkrs.

I'd say the differences in cabinet construction techniques between guitar cabs and home audio speaker cabs largely accounts for which are front- or rear-loaded.

In home audio, rear loading is impractical from a mfg standpoint because the cabinet is jointed and glued together to minimize panel resonances and rattles. A home audio cabinet is simply not going to be built with a removable back panel, so the drivers have to be front-loaded. It's also true that there's an advantage in getting the drivers in front of the baffle to minimize baffle reflections. Many, however, are routed so the speaker is flush with the front of the baffle.

Conversely, most guitar cabs have removable back panels, making rear-loading practical, and--as you said--removable front panels and grille cloths aren't particularly desirable in guitar cabs.

[JohnnyB]

...there are so many variables between them in terms of speaker type and cabinet construction that describing the difference between the two methods of speaker mounting would be impossible. Only way to really do that would be to A/B cabs that are identical except for how the speakers are loaded.

That's so true. What makes far more difference is how damped or resonant the baffle is, how solidly it's attached to the cabinet, what the baffle and cab are made of, how thick they are, the baffle dimensions, the cabinet dimensions, the damping scheme (open, closed, or ported), and how tightly the speakers are mounted to the baffle. Rattles and resonances have far more influence on the final sound in a guitar cab than which side of the baffle the screws are on.

Guitar speakers range from 8" to 15", most being 10" or 12". In all cases, the cone diameter is large enough to guarantee that the treble range has a very narrow dispersion (i.e., the treble "beams"), which means that 3/4" of baffle surrounding the cone will have little if any effect on the dispersion pattern.

In home audio speakers midrange and tweeter diameters are optimized for dispersion patterns in their assigned frequency ranges. In these cases the baffle mounting has a profound influence on the dispersion. It simply doesn't apply to a 12" guitar speaker with a relatively limited frequency range.

[HSB0531]

Saw this post and had to add this........

Saw this Post & thought you all might be interested

Jim Falco

[Craig S]

That's so true. What makes far more difference is how damped or resonant the baffle is, how solidly it's attached to the cabinet, what the baffle and cab are made of, how thick they are, the baffle dimensions, the cabinet dimensions, the damping scheme (open, closed, or ported), and how tightly the speakers are mounted to the baffle. Rattles and resonances have far more influence on the final sound in a guitar cab than which side of the baffle the screws are on.

This seems to be the the answer... I tested two cabs, one a rear loaded Peavey tweed 112e and non-branded front loaded pro-made cab..both about the same physical size... The Peavey had a Sheffield and the other cab a V30. Firing them both up using a Classic 30 I sampled both cabs and then switch the speakers. This is what I found with both speakers the 112e was in both cases the lighter sounding cab by direct comparison. The Peavey's speaker baffle is less solidly conected and thinner than the no-name cab. With both the V30 and the Sheffield the no-name cab had more shimmer and thump, in fact doing a pretty good 4x12 emulation. Construction does appears to be a important tone factor.

[JohnnyB]

The Peavey's speaker baffle is less solidly conected and thinner than the no-name cab. With both the V30 and the Sheffield the no-name cab had more shimmer and thump, in fact doing a pretty good 4x12 emulation. Construction does appears to be a important tone factor.

A speaker is a type of electric motor. Any motor (or engine) cannot surpass the chassis to which it is attached. To reach its fullest potential the chassis (or speaker cab) has to be as rigid and resonance-controlled as possible. A 500 hp V-8 dropped into a Ford Pinto w/o chassis/mounting modifications will waste a good deal of its power twisting the frame and causing wheel-hop.

[Luke]

Well I played a Bogner and VHT 4x12 side by side, they are 100% identical, made by the same cabinet builder, of the same dimensions and materials and the only difference was front versus rear mounting.

The front loaded cabinet spread the sound out more and had more treble response. In the end, the VHT sounded off to my ear so I went with the Bogner as it was more what I was use to.

BTW, Diezel has his cabinets made by this same builder as well. All any of these three companies do is add the speakers and wire them up, the wood working/tolexing is all farmed out.