Low-end cab for distorted guitar

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Hi,

Best bass rig I've ever played with was a Fender Bassman valve
amplifier with Trace Elliot 4x12 bass cabinet, sublimely reactive.

I really can't see the point of the 1x15, whatever you imagine.
A guitar 4x12 is easy enough to EQ for bass, just not as good.

The classic set up of a a 4x10 plus 1x15 for bass (which I
have) is a bit poor, the 4x10 being far better for guitar
than bass, the 15 saves the day, and good alone.

rgds, sreten.
 
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First order of business seems to be recognizing the fundamental at dropped D is around 72Hz I think. You will be fighting a harshly losing battle trying to accommodate response below this. Ports at this frequency and above are a compromise you don't want to make right at the instrument. If someone wants to do that to themselves later with some 4" desktop PC speakers, let them have it.

In keeping with broadly accepted ideas about "musicality" and certainly with well known ideas about efficiency, you would choose the light, large diameter driver cone.

With all that in mind, to satisfy a desire to knock yourself out with major guitar low end, you might need something like 4 x Eminence Deltapro 15A in 3 cubic feet sealed per driver. To do it right with one guitar amp you would need to make a seriously designed passive crossover, with all the attendant problems of phase relationship at the crossover frequency, so as not to have your 12's for high end (or whatever) fighting your 15's near there. If you were to use a separate amp for the low end cab, it might be even harder to sew the two cabs together, but the way guitar heads are commonly designed (for higher output frequencies in general) that may not work out so well anyway. Exactly where to put the crossover point will be tricky business to preserve your mid tone while getting everything else you want. If you end up slightly overdriving 4 15's in this arrangement, you're doing it wrong. It's way more than you'd ever need.

That's my 5 cents.
 
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i think tubelab is on to something but rather then synthesis simply splitting your signal into two paths with a splitter buffer. one chain feeds your stomp box guitar amp (distorted) the other to your SVT bass bin combo(clean)
you could chop the high end off the bass amp feed so as to not sound to much like a second guitar while maximizing clean bass gain
maybe?
 
And a speaker rated way over the amplifiers output will not. What am I not seeing here?
What you don't see at all is that in the incredibly bad speakers you use as an example, the rating means nothing, it's pure imagination. Capisce?
An EVM15L (as an example of a *serious* speaker, there are more in the same league) is rated "only" 400W RMS ... and I'm certain it's true.
There must be *some* reason for PA guys to use expensive EV/JBL/Beyma/RCF/Faital/Eminence/TAD/PAS and not 20000W Car speakers.
Just the names they choose: "BlackPlague/Terminator/Bomber" etc. should raise a couple red flags.
As well as the cheesy 30's SF movie looks, gold plated frames, ridiculous "Burger King Stacker" style magnets, shiny cones with little fluo stars and planets stamped on them, etc.

Of course, if you don't want to "see", it's your choice.
Closing your eyelids tightly shut sure helps.

*If* you are really searching for a gut wrenching sound (although you should forget about being blown against a wall, that's physically impossible unless you are close to an explosion) , search the catalogs of EV/JBL/Beyma/RCF/Faital/Eminence/TAD/PAS to see what the real Pros use.
 
You may want to read this:

Power Handling Vs. Efficiency

...which is a long-winded explanation of what Mr. Fahey just said.


Or, as I implied earlier, you don't get loud by using more power - you use more efficient speakers. And in the bass region, a major efficiency loss is the coupling with the air, so you need lots of surface area. Your BTTF reference is a good one, but was the size of the speaker that knocked him over, not the wattage.
 
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This whole idea started one day when I played my guitar, distorted, through a Peavey TNT 150 bass combo that has a 15 in it. The bass response was amazing and it had "kick". All I dreamed of doing from that day on was to get the same 15" "kick" but louder, as in stage loud. I've played my guitar through other bass rigs, ie; Hartke's, Ampegs,etc. with that same result. Wicked bass response from my guitar.
I understand what you're saying JM about "The Black Death" 15 and the hoopla that the manufacturer puts out about it. I thought the higher wattage rating would "handle" the Ampeg output. I was also thinking that wether it's a "car" speaker or not that as long as you match impedance, build the right cab, give it the bass notes it was built for, and of course, not under rate the wattage, that all would be fine. Seeing all the responses it would seem I'm barking up the wrong tree. Another problem is that I'm tenacious and I won't give up till I get that BTTF-like effect.
I've already cooked an EV15m and a JBL2226 trying this experiment. That's why I thought the Eminence Kilomax 15 would do the trick, but alas, I'm still wrong.
 
. Seeing all the responses it would seem I'm barking up the wrong tree. Another problem is that I'm tenacious and I won't give up till I get that BTTF-like effect.
I've already cooked an EV15m and a JBL2226 trying this experiment. That's why I thought the Eminence Kilomax 15 would do the trick, but alas, I'm still wrong.

Besides all the good feedback you're getting here, you might give the fEARful DIY cab forum a try. Many guys over there play extended range basses or other instruments that cover the same frequency range you're interested in, often with mucho distortion and at very high sound pressure levels. As a consequence, they have developed many strategies for not blowing stuff up that you might find useful. Proper cab tuning is a pretty good place to start. ;)
 
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Joined 2005
I've already cooked an EV15m and a JBL2226 trying this experiment.

designers do very extensive work to improve powerhandling....and I suppose they expect a big woofer to use most of its Xmax at full power
but if it doesn't move much there will be no cooling ;)

and your guitar alone probably won't make it move very much
so the lack of cooling would for a big woofer mean much less power handling

and it might be a good idea to have your amp checked for errors
and another thing .... how much voltage signal do you feed into that SVT power amp ?
 
I'm taking the output of my Marshall JMP-1 and running into the SVT input. SVT master volume is full up, and I vary the input gain until it just about "peaks". I use the compression on the SVT as well. It sounds real good and thunky at moderate volumes (rehearsal volume) but starts to choke and is ready to fry if I go any higher. Seems like I'm trying to cram a 5lb bag of ___ into a 1lb bag. The Kilomax doesn't like it. I've been frying my brain with all the info so far, but it all makes sense. There has to be "the right combination" to achieve what I'm looking for. As for the integrity of the SVT, it runs an 8x10 with a normal bass correctly and is up to snuff.

Thank God for this forum or I'd be buying high powered speakers for no reason. I do know there IS a solution though.
 
I've already cooked an EV15m and a JBL2226 trying this experiment.
Thank God for this forum or I'd be buying high powered speakers for no reason. I do know there IS a solution though.
Yes there is: use 4 (FOUR) of them.
You have already spent that money or more.

Electro-Voice EVM-12L Black Label 12" Speaker | Musician's Friend
EVM12L Black Label model 400W RMS (Real!!) each.
U$ 279 each.

Eminence Delta Pro-12A 12" Cast Frame Driver 290-510
Eminence Delta Pro-12A The Eminence built clone. 400W RMS
U$ 135 each.

Both have same specs 15" versions, so if you don't want a 4x12" you can build 2 large 2x15".
Bass , punch and SPL will be MASSIVE.

Spend once and spend wise.

NO single 15" or 18" will do what 4 of these babes can do with ease.

Won't even post about other more expensive options .
 
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Well, the fact that an SVT can fry speakers isn't exactly a surprise. And I hope by now we've gotten across the idea that if a speaker is not specifically designed to handle the string 'pop' of a guitar or bass, it isn't going to last long at high volumes.

But power handling aside, I think perhaps your issue is one of coherence. Musical instruments don't have crossovers in the bass region. The slap of a bass or the thunk of a bass drum is the result of the waveform being perfectly in phase with itself and I think that maybe you're having trouble because you're trying to "add more" to a 4x12. Remember, the Peavey that set you on this path only had one speaker, so it had to be 'time-aligned'.

What's everyone else think?


(Actually, I know what JM thinks, and I agree - there's a good chance that a slightly oversized 4x12 with EVM12Ls will do just what you want, and you wouldn't need the SVT. (Zach agrees, as well! :D))
 
This whole idea started one day when I played my guitar, distorted, through
a Peavey TNT 150 bass combo that has a 15 in it. The bass response was
amazing and it had "kick". All I dreamed of doing from that day on was to get
the same 15" "kick" but louder, as in stage loud. I've played my guitar through
other bass rigs, ie; Hartke's, Ampegs,etc.
Wiith that same result. Wicked bass response from my guitar.

Hi,

Probably true but a pain in the proverbial for a bass player,
live. Do your job, and don't get in the way of anyone else.

rgds, sreten.
 
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Ex-Moderator R.I.P.
Joined 2005
talking about overdrive :eek:

your SVT is fullfunctional headamp
I dont think its clever to run it at full power ... and then even worse, driving with lots of gain from yet another headamp:scratch:

overdriving the output stage of a big solid state power amp might not be good at all
do it the other way
try overdrive the input of your SVT instead
 
Probably true but a pain in the proverbial for a bass player, live. Do your job, and don't get in the way of anyone else.
Dude, if one octave is all you need, you got to be the boringest bass player ever! :joker:

Seriously, what's with bass players using tens and tweeters? This "get in the way" thing isn't an unheard argument, but it seems like a one-way street.

Let's just say there are plenty of bands with two guitars who both play lead or rhythm at the same time. It's called musicianship. ;)
 
but maybe instead consider buying better 12" than you have now
for what you want, I would say 8x 12" .... and you could ofcourse double that if you like :D

I think the problems start with that when someone actually wants midbass "punch" from their speaker stack. A 12" "guitar" speaker designed for overall sound normally runs with an Fs around 90Hz and a Qts around 1. You can get a lot of boing out of that, but not punch and bottom end extension. To get rock bottom from the guitar you'll have to start with a speaker having a sealed F3 around 72Hz, and to get that you'll need a driver with an Fs around 40Hz.

They don't make any "guitar" speakers like that.

Guitar speakers with a lower Fs (70Hz) and lower Q do exist but start to sound very "forward" and lose character in the higher frequencies. A 2-way with dedicated midbass and top end cabinets might be a lot of cost and effort to get working right, but at least there would be a physical capability for it to perform as desired in the end.
 
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