#1
Hi all. Long time forum lurker and squeaky fresh new member here.

I wanted to pose a technical question, as I seek the input of those more knowledgeable than I...

Ruling out my guitar being the cause of this problem (because I've made this happen with 2 guitars and know it's not a guitar electronics / output issue), I own an Ampeg SS140 amp. I've noticed this happens sporadically: when I've been playing for a period of time heavy or clean, the overall volume level will drop to a barely-audible level, then come back in and waver in the quiet-zone. But not nearly as high as it otherwise would be, until I go over and turn the knob a little bit more, immediately blowing my ears off as the volume level returns to its normal level. What possibly could be the cause of volume dropping out and wavering randomly until I turn the knob again...Power amp? Pre-amp? I'm stumped. The amp/indicator light never turns off when this happens, it's just purely a volume issue.

Any ideas?
Last edited by mista_earth at Apr 8, 2011,
#2
A friend of mine had a similar problem because he didn't drive the power amp enough. His preamp volume was at like 2 and it phased in and out in volume a bit.
CAPITALISM
Quote by diofan88
Naked with a bowl of cereal with headphones.
#3
I see.

It might have been helpful to be more specific, I have a SS140 2x12 combo amp (which does have inputs for a power amp).

By 'driving' do you mean just turning the pre-amp volume up to the point where the power amp is steady and won't waver as much? This is not very desirable because it seems the volume won't really stay steady unless it's at a deafening volume. Why is driving the power amp even necessary? Is it a symptom of an internal power amp that is going bad? In such case, easily repaired? I mean I know my amp has extreme gain for days, and I wouldn't be surprised if it even strains itself, but, how can I boost my power amp?
Last edited by mista_earth at Apr 8, 2011,
#4
From my knowledge, a power amp is looking for a line level signal, which is what the preamp is for, aside from tone shaping. Would probably help to turn up your preamp
CAPITALISM
Quote by diofan88
Naked with a bowl of cereal with headphones.