Is It Possible to Cut the Power Rating of an AC30?

[Pink Unicorn Horsey]

A discussion in another thread got me thinking…

My Vox AC30 is rated at 30 watts. By removing tubes and running the amp into one speaker rather than two, is it possible to cut the AC30's power rating in half (effectively turning it into something like an AC15)?

Although the Vox is 30 watts, it's a *loud* 30 watts. Anyone who has ever played through an AC30 realizes this.

- Keith

 

[sosomething]

Re: Is It Possible to Cut the Power Rating of an AC30?

Hmmm......... Without playing around with an AC30 - and I haven't, outside of trying a few out in stores - I don't know. What power tubes is it running on? A quartet of EL84s?

Some circuits react strangely to this, and at the moment I can't say what the best way would be to do it, if it can be done at all. Also, depending on how the speakers are wired, just plugging into one speaker may not actually cut the impedance in half, either.

Paging wahwah!

 

[baritone]

Re: Is It Possible to Cut the Power Rating of an AC30?

I'm not an amp expert, but I'm pretty sure it is dangerous to just take some tubes out. Some internal wiring would have to be redone to make sure your amp didn't get damaged. The modern Custom Classic series from China has a switch which changes the circuit a little and drops it down to 22 watts. But, yeah, any 30 watt tube amp can be expected to be loud as heck.

 

[jeremy]

Re: Is It Possible to Cut the Power Rating of an AC30?

not sure, i know in many class a/b push pull fixed biased amps you can pull a pair and half the impedance safely.

your amp is cathode biased which may make a difference.

you could switch the power tubes to triode mode, that would cut power some and one switch could do all the tubes.

 

[Pink Unicorn Horsey]

Re: Is It Possible to Cut the Power Rating of an AC30?

Why's that?

 

[B Bent]

Re: Is It Possible to Cut the Power Rating of an AC30?

Cause you'll fry it Keith!!! Christian and I were talking about it on the phone earlier.

 

[Pink Unicorn Horsey]

Re: Is It Possible to Cut the Power Rating of an AC30?

I believe you. I'm just wondering about the technical aspects of it. Perhaps that's too much for a forum thread...just wundrin'.

 

[newking70]

Re: Is It Possible to Cut the Power Rating of an AC30?

yea, get an ac15 :24:

 

[Pink Unicorn Horsey]

Re: Is It Possible to Cut the Power Rating of an AC30?

Is it possible to cut the AC30's power rating in half (effectively turning it into something like an AC15)?

yea, get an ac15 :24:

I'm not interested in getting an AC15, but having the option to cut down the power in my AC30.

- Keith

 

[jeremy]

Re: Is It Possible to Cut the Power Rating of an AC30?

triode mode will do that, also make the tone a little creamier

 

[Gearjoneser]

Re: Is It Possible to Cut the Power Rating of an AC30?

Keith. If your AC-30 is a newer one with an FX loop, you might try putting a rack unit with a volume knob in the loop. I use an Alesis Nanoverb.

That way, you can mix in some reverb or FX, but also use it as an extra volume control.
You can trim off some volume that way while keeping the amp running strong. It's like a post EQ volume knob.

 

[Pink Unicorn Horsey]

Re: Is It Possible to Cut the Power Rating of an AC30?

Sadly, it's not one of the AC-30CCs. Mine is the version that came out just before those.

- Keith

 

[Gearjoneser]

Re: Is It Possible to Cut the Power Rating of an AC30?

I'd use an OD pedal then. Turn the OD's volume down, and adjust it's gain to melt with the AC-30's normal sound.

Do you still have the Klon? It's good at adding gain without too much coloration.

 

[Pink Unicorn Horsey]

Re: Is It Possible to Cut the Power Rating of an AC30?

Hellz yeah, I've got the Klon. See, the thing I like most about the AC30 is the chimey clean, so I wouldn't want to dirty things up when I'm turning it down. I don't want to use the volume knob on my guitar to turn it down, because I lose the fullness of the Vox tone. It's a tricky thing. Know what I'm sayin', Joe?

Of course, for dirt, the Klon may be just the trick.

- Keith

 

[Low_fidelity2100]

Re: Is It Possible to Cut the Power Rating of an AC30?

what speakers are in it? If your running the celestion blues, those are super efficient speakers (100db @ 1w/1m I think). Putting in a less efficent speaker would help drop the volume a bit. Down side being it would change the sound somewhat too.

 

[Pink Unicorn Horsey]

Re: Is It Possible to Cut the Power Rating of an AC30?

Yeah, I've got the blue alnicos, and I wouldn't want to remove one of those -- I paid extra for those babies. Good thought though.

- Keith

 

[Low_fidelity2100]

Re: Is It Possible to Cut the Power Rating of an AC30?

Yeah, I've got the blue alnicos, and I wouldn't want to remove one of those -- I paid extra for those babies. Good thought though.

- Keith

Yeah, I wouldn't wanna remove em either, haha. It would decrease the volume though.

Why not just get an attenuator? You could keep the volume up to where you like it, for fat cleans. Rather than cranked for OD like most people who use attenuators. Then just use the attenuator to nudge the volume back down a little bit.

 

[LesStrat]

Re: Is It Possible to Cut the Power Rating of an AC30?

A friend of mine was using the AC30 on tour last year (now he uses a BadCat). He would crank it, mic it, and wrap it in a moving blanket.

 

[Pink Unicorn Horsey]

Re: Is It Possible to Cut the Power Rating of an AC30?

Yeah, I wouldn't wanna remove em either, haha. It would decrease the volume though.

Why not just get an attenuator? You could keep the volume up to where you like it, for fat cleans. Rather than cranked for OD like most people who use attenuators. Then just use the attenuator to nudge the volume back down a little bit.

I do use an attenuator -- a 16Ω THD Hot Plate -- but I was hoping there would be a way to bring it down even more without sacrificing tone.

 

[James Rock]

Re: Is It Possible to Cut the Power Rating of an AC30?

There must be a mod out there that can change the power rating (as in a similar design to whats in the power section of matchless DC-30's) if you can find one that would solve your problems but I haven't seen any so im sorry i can't really help but I'm sure if you can find a good amp tech they can tell you if its possible.