Taming a bright cab or brightening on a dark cab w/o speaker replacement

SimplyTH

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Hey there,

So currently have two old Carvin Cabs, a 4x12 and a 2x12. the 4x12 has Celestion G12T-75s in it (I think) and the 2x12 has Carvin British voiced Speakers made by Eminence. My amp is a Sunn Sorado (old 60 watt bass amp with KT88s).

The 4x12 is incredibly dark, in my current band I use a looper pretty heavily and everything becomes mud even with just one loop and a lead line. EQ on the amp does not seem to help much unless I turn the bass all the way down, at which point the tone just sounds like garbage. The 2x12 is the exact opposite, no problem with clarity but it is very harsh especially when using gain. When I use my EQD Plumes it gets very ice-picky, the more gain the worse it gets. If I use my bridge pickup I have to turn the treble knob on the amp to zero, the tone knob on the plumes all the way to left and turn down the tone knob on my guitar about 80% of the way to tame the icepick. At that point while the icepick is gone the tone is lifeless and dull.

The other problem is I am pretty strapped for cash right now but I have a bunch of gigs and a recording session soon so I would like to have some kind of fix for this. I would prefer to get the 2x12 useable because it is way more practical for gigging. Would putting one of the Celestions in the 2x12 help? Get a different (cheap) overdrive? Some other relatively cheap mod/trick?

Thanks
 

archetype

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Hey there,

So currently have two old Carvin Cabs, a 4x12 and a 2x12. the 4x12 has Celestion G12T-75s in it (I think) and the 2x12 has Carvin British voiced Speakers made by Eminence. My amp is a Sunn Sorado (old 60 watt bass amp with KT88s).

The 4x12 is incredibly dark, in my current band I use a looper pretty heavily and everything becomes mud even with just one loop and a lead line. EQ on the amp does not seem to help much unless I turn the bass all the way down, at which point the tone just sounds like garbage. The 2x12 is the exact opposite, no problem with clarity but it is very harsh especially when using gain. When I use my EQD Plumes it gets very ice-picky, the more gain the worse it gets. If I use my bridge pickup I have to turn the treble knob on the amp to zero, the tone knob on the plumes all the way to left and turn down the tone knob on my guitar about 80% of the way to tame the icepick. At that point while the icepick is gone the tone is lifeless and dull.

The other problem is I am pretty strapped for cash right now but I have a bunch of gigs and a recording session soon so I would like to have some kind of fix for this. I would prefer to get the 2x12 useable because it is way more practical for gigging. Would putting one of the Celestions in the 2x12 help? Get a different (cheap) overdrive? Some other relatively cheap mod/trick?

Thanks

Has this rig ever sounded right? If so, has anything changed since it sounded right?

Good luck with this. You may not be able to solve the issues without the liberal application of money. Speakers are like a mastering stage for amplification: a final EQ on everything. It sounds like you've got the rong speakers in both cabs. The bass head isn't helping any, as the bandpass for each of the TMB controls is optimized for bass, not guitar.

Maybe this sounds wacky, but consider trying the cab temporarily with the back removed. It doesn't add treble, but it sometimes alleviates the lower end thump that can dominate the full range of the cab. If removing the back improves the tone, add board(s) to the back so it's about 1/3 open. It's just the cost of a board from the hardware store. It won't project as much as the sealed cab, but it may balance the tone somewhat.

The cheap possibility for the 4 x 12" is a treble booster.

Honestly, I'm puzzled. Again, did this ever sound right? You may just have the rong stuff, all of it.
 

SimplyTH

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Has this rig ever sounded right? If so, has anything changed since it sounded right?


Honestly, I'm puzzled. Again, did this ever sound right? You may just have the rong stuff, all of it.

Well, it could be a couple of things, the new material we have been working on calls for a lot more gain then our old stuff. I did also switch from using a Mustang to a Tele recently as my main guitar for a variety of reasons, mostly I don't feel super comfortable with gigging a lot with the Mustang any more. The Mustang sounded nice through the 4x12 probably because that guitar has so little low end to start with. I would say playing with higher gain has made more of a difference though.
 

mexicanyella

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Can you run both cabs together with that head, and can you get away with doing so in the gigs and/or recording session?

If so, try putting the 4x12 on top of the 2x12.

1) what you hear out from the cabs a bit, the blended sound, might sound pretty good.

2) the tooth-shattering 2 x 12 will be firing at your knees, and you’ll be more on-axis with the darker 4 x 12, so you’ll be in the beam and receiving whatever upper mids and highs it has to give.

3) for recording, you now have some mic options to blend and choose between: bright cab, dark cab, more distant ambient mic receiving blended sound and some room ambience. (And if either cab has an open back, you could employ a phase-reversed back mic for an additional flavor, plus phase experiments by not flipping its phase.

Or, if the ohms math works right, what if you put two of the Celestion 75s from the 4 x 12 in the 2 x 12, maybe darkening it, and put the two Carvin speakers in the now-empty two holes of the 4 x 12, possibly giving you a better blended tone?

If the ohms math would work out for you, and with a little luck, that might make both cabs useful together or singly.

But I’d try my first suggestion first, if using two cabs together would fly in your situation.
 

Dacious

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You could try revoicing the amp with some smaller numeric coupling caps. It's probably running 0.049s or 0.1s - 0.022s would be more guitar like.

What impedance are the speakers? If they're all 16 or 8 ohms you can swap them. Try taking the back off the 412. It might sound crap, might sound great.

Drop your bass and treble on the amp. Reduce volume.

An eq pedal will help.
 

archetype

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Well, it could be a couple of things, the new material we have been working on calls for a lot more gain then our old stuff. I did also switch from using a Mustang to a Tele recently as my main guitar for a variety of reasons, mostly I don't feel super comfortable with gigging a lot with the Mustang any more. The Mustang sounded nice through the 4x12 probably because that guitar has so little low end to start with. I would say playing with higher gain has made more of a difference though.

My serious answer: Don't focus on gain. Focus on what works. Back off the gain, get a clean tone that cuts though, and stop thinking about it. No one in the audience is thinking about gain. Dial in a tone that's works (it doesn't matter if you think it's good) (and the numbers on the knobs don't matter).

Just play. Set treble on 10 and the rest on 0 if necessary, and just play. The crowd thinks about what you play and nothing else. The only ones thinking about tone are you and the 3 guys leaning against the back wall judging you harshly against what they'd play if they could play at your level.
 

homesick345

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A chair (speaker relative height plays a lot on the treble response to your ears/tightens the bass)

OR turning the cab 180 degrees, you'll have less highs more mids

in short: cab placement
 

schmee

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Are the backs removable? Try taking it off. It will clean up the sound immensely.
How deep are the cabs? Very deep can be woofy especially if closed back.
 

SimplyTH

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A bit of an update that might totally solve this problem if someone can answer it.

The amp is at my bandmates house where we practice so I often don't get a chance to go and mess around with the amp outside of band practice but since this was such a problem I went over to experiment and see if I can fix it. While I didn't fix the problem I did discover some interesting things.

1. While the 4x12 is a much darker it is still prone to harsh ice pick sound if the treble on the amp is cranked up.
2. I got the icepick problem on a completely different amp head (a carvin guitar amp head).
3. The icepick only occurs on the top three unwound strings (I use ernie ball 11-48s)
4. While the icepick is much worse of the bridge, you can hear a bit of it on the neck pickup too.
5. The ice pick frequency is probably somewhere around 2.5k would be my best guess, but even using an eq pedal I have a hard time getting rid of it.
6. I do not get any icepick on my home practice amp (a Fender Pro Junior) using I crank the treble all the way up and really hit the strings hard.

I assumed the ice pick was coming from the 2x12 since it only showed up when I switched cabs but now that I am able to recreate it pretty easily on the 4x12 I don't think it is the 2x12, I just think the 4x12 is just that dark. The question is what is the constant here that is causing the problem? Is it that the practice space has cement floors and walls as opposed to the carpet I have in my apartment and the ice pick frequencies are resonating? Is there something about the pro junior that eliminates ice pick? I read in another thread that too much voltage coming out of the wall can cause icepick on amps, and the electricity in our practice space has always been, uhh, funky to say the least. Sorry if the questions totally pivoted but I really want to figure this out. Thanks!
 

SimplyTH

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Update in case any was curious:

Gaffer's tap on the grill right on the center of the speaker cone solved the problem for the 2x12. Still very bright (that's fine) but no more ear drilling ice pick frequency.
 




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