VOX AC4HW Style amp with Reverb that doesn't hum

scovell001

Hey to all on the forum. About 18 months or so ago I bought a VOX AC4HW1 from a sale at one of the guitar stores.

Very simply, stuck a Blue in it, loved the tone, didn't really like the white tolex & it didn't have reverb. But, what really killed it for me was that it hummed like goodness knows what. Just turning it on with no volume & it just hummed so loud that everyone commented on it. So, it had to go back!

I still think about that amp & love the Vox tone &  just wondered AC4HW1 owners out there, are there versions which are silent ? & is there a similar amp (or boutique amp builder) who makes/would make one in black tolex & add Reverb to it ?

4114Effects

Sounds like a great little project. I know there're a few great builders on here would be up for that kind of thing. I'd be happy to discuss such a build too. :-)

thermionic

Single-ended power amps are inherently more susceptible to hum, aren't they?

jpfamps

thermionic said:

Single-ended power amps are inherently more susceptible to hum, aren't they?

Yes.

You need more filtering in the power supply as the output stage has poor power supply rejection (unlike push-pull amps).

Shouldn't be too difficult to mod this.

Hum from the filaments can also be a problem

I've built SE amps that you can't tell are on unless you have your ear right up against the speaker.

Triode mode, if it's an option, will generally have higher hum too.