LETS FACE IT

[RCGPNY1]

I am amazed at when a person asks for a certain brand of speaker cab. Aside from brand loyalty, i.e." I like Marshall cabs", the differences are much more in the speakers you load into it. If everything is equal...wood thickness and type(ply,mdf) and the type of joints...then there is no magic than can imparted into a speaker cabinet. Sometimes I notice people overthink speakers for guitar...Such as " I want Thiele/Small specs for a guitar speaker". Someone found out that hifi folks have neen tuning bass reflex enclosures for years and thought it would be a good thing for guitars...not so. Having owned cabs from most of the major, and some smaller builders....there was very little difference between say, a divided by 13 cabinet and a Bruno or Mojo made cab. All made well with good application of covering, clean insides(no excess glue) good jacks, hardware....So IMHO it doestnt pay to intellectualize over the slight differences...again the drivers going into it are gonna be the deciding factor. It also speaks to the sometimes overblown costs of some builders cabs.

[rooster]

OK, I'll face it.

[Geeze]

Amen. Having built undersized, oversized and ported Thiele spec cabs all using the same set of speakers I've not heard the 'magic' of any design. In fact my favorite 'sounding' cab was a failed attempt to make the smallest 2x12 cab I could - missed on magnet clearance - but the 2x10s sound great.

Russ

[Structo]

Yeah, it can get mighty expensive buying and trying different cabs, as well as speakers.

Since most times you can't try before you buy.....

But I do think the size of the cab, open or closed back can change the way a speaker sounds.

In my case I tried a few different speakers and cabs for my Dumble clone.

I finally settled on using my old Vox 2x12 which is pretty big and two EV 12L's.

I had the 12L's in a cheaper Lopoline 2x12 and it just sounded kind of boxy and dead.

[xtian]

+1. I remember being astonished that the Fender HRD sounded so much better than the Blues Jr. I ran many different heads thru the HRD's larger, open-backed 1x12 cab, and I really liked the sound of that cab.

[ER]

If you only wanna sound like 98% of the rest of the stuff out there it doesn't matter, but if you are going for the last 2% it can make ALL the difference.

I don't know why someone would go through the trouble of building an amp if they aren't going to go for that last little bit or can't hear the difference.

[jaysg]

Well yeah, but it's so much fun! All the planning and hoping, then you're done and you crank it and it's cool. No cooler than any other cab, but still -- look what I built

[Cantplay]

Thats like saying all acoustic guitars sound the same.

baffle thickness, open or closed back(and opening size), volume, and material all influence how a cab sounds.

A bare oiled pine cab will also soind different covered in tolex.

john

[Scumback Speakers]

Cab design can play a huge factor in how speakers sound, and vice versa. I've had clients get two identical speakers from me, and swear one was bad, broken, etc. in one cab, and awesome in the other...the difference being 1" wider and taller than the other.

I told them to switch speakers in the cabs.

The next day they emailed me to tell me the bad speaker now sounded awesome in the other cab, and the good speaker now sounded bad in the other cab. They wanted me to explain that.



The client figured it out, of course, but he was amazed the difference that 1" taller and wider made over the other cab. No, I never got the dimensions, he just told me the differences between the two.

Yes, he shitcanned the one cab and had an identical cab made like his smaller one, and he's been happy ever since...at least he hasn't called or emailed me tell me otherwise!

So don't discount the cab size/volume/type, etc. It can make or break your tone IMO.

[Phil_S]

So don't discount the cab size/volume/type, etc. It can make or break your tone IMO.

So just how does one go about figuring this out? It seems to me there is a certain randomness to it. I know there is a lot of engineering around cab dimensions, the golden rule, etc. but, really, where does the rubber meet the road?

As an example, I'll cite that silly 2x 5" project I've got on the shelf at the moment. I'm convinced that the cab size and style (closed back) is somehow wrong, but am clueless about what to do about it.

[RCGPNY1]

If you reread my OP I did talk about materials and construction techniques. What I am talking about is manufacturers making claims of superior sound because of some kind of magical mojo engineering.
With proper technique and good drivers we can probably put together
a great cabinet,with materials du jour, for less than $400. Also keep in mind that the dimensions of the Marshall 4x12 was because Jim like the way the JTM45 head looked ontop of it.

[Scumback Speakers]

So just how does one go about figuring this out? It seems to me there is a certain randomness to it. I know there is a lot of engineering around cab dimensions, the golden rule, etc. but, really, where does the rubber meet the road?

I believe Eminence used to make a software program that did the math on the volume requirement behind the speaker you were using. It was PC/Windows based IIRC, did not run on a Macintosh, so I couldn't use it.

I wound up with the sizes I have by trial and error, but I did a lot of research first, noting which cabs I liked, and didn't like, then keeping their specs for reference.

So I'm NOT the guy to tell you what will work for your amp/speaker needs, since I only used my speakers to evaluate the end tonal result (sorry!).

Obviously the 4x12 size was duplicated for aesthetic reasons as well as keeping to the original spec. But even then improvements were subtle, which is why I wound up with the late 69 spec cab that I felt sounded the best.

The 2x12 and 1x12 cabs I offer were derivatives off of those, but without the size involved.

[Aurora]

I've been fiddling with loudspeakers and design for well over 30 years now, but mainly for HiFi and some PA. Loudspeaker design theory is very well founded since the late 60s, courtesy of Msrs Thiele and Small who did the main work not knowing of each other, hence the now well defined T/S parameter system. There are also several very accurate design and simulation programs available these days, - some of them are also free on the net.
However, they mostly deal with closed or various versions of vented cabs, and the typical guitar open back box does not apply to these rules, as it is rather more of a quasi version of an open baffle design, or lends is basis from the old classical reflex cabs, where the vent area wasa set equal to the effective membrane area. Tested with modern methods this approach fails completely vs todays ruling algorithms. That in itself does not say that a typical open back guitar cab doesn't sound good for guitar, - maybe quite the contrary..... but it still needs to be considered as an open baffle, as the opening is far to big to give any significant loading to the speaker element...

The next problem is that T/S parameters for the most popular guitar elements are not known, Celestions included. Reports have also been made that production spread is far to large for reliable T/S design parameters. This may be the reason for difference with the two speakers mentioned. In general terms the cabinet really only affects the lower end of the emitted spectrum, - mids and highs are mostly determined by the element itself, and not by the cab, - open backs and baffels in particular....
It is still the same physics - HiFi o guitars....

[M Fowler]

I have an old Peavey Speaker Manual that shows how to build PA cabs and has all the build measurements, box volume, Hz, etc.

Years ago I built all the monitors and PA boxes for my band. Good reference but probably out dated?

[katopan]

Yes, he shitcanned the one cab and had an identical cab made like his smaller one

I like that it was the smaller cab he liked better. Lots of people assume a bigger cab will sound better (even for guitar) but it's not necessarily true!