Will raising the bias of my amp give me more clean headroom?

[ggunn]

lotsa early fenders had these balance adjusts... which in most cases were modified to adjustable bias... lprobably the mod which was the most popular...

That depends on what you mean by "early" Fenders. My '68 - '69 Super doesn't have a balance pot, but a friend's mid/late 70's Super does have one.

 

[ranjam]

we mic drums guitars and keys through the PA all the time. As long as the PA can handle it there are no problems with the vocals.

No, no. What I am saying is putting the guitar or bass through the monitors, not just in the mains. I have done gigs where there are multiple monitors and monitor mixes with vocals and all instruments for each of us, but those are preciously few and far between. Usually it is just vocals through two wedges up front, and the drummer gets one if he's lucky. And it kinda sorta makes some sense; you want to hear the vocals clearly and cleanly, since that's where most of the time we get our cues. Your on stage amp should have enough to give you a 'stage volume' that everyone hears. For big stages or outdoor festival-type gigs, I've used two identical amps or two identical cabinets from one amp; one on each side of the stage pointing in, as a side wash. That's an experience you don't forget, and you never want to go back to Legion gigs playing 'Brown-eyed Girl' again.

 

[Lt. Bob]

No, no. What I am saying is putting the guitar or bass through the monitors, not just in the mains. I have done gigs where there are multiple monitors and monitor mixes with vocals and all instruments for each of us, but those are preciously few and far between. Usually it is just vocals through two wedges up front, and the drummer gets one if he's lucky. And it kinda sorta makes some sense; you want to hear the vocals clearly and cleanly, since that's where most of the time we get our cues. Your on stage amp should have enough to give you a 'stage volume' that everyone hears. For big stages or outdoor festival-type gigs, I've used two identical amps or two identical cabinets from one amp; one on each side of the stage pointing in, as a side wash. That's an experience you don't forget, and you never want to go back to Legion gigs playing 'Brown-eyed Girl' again.

these kinds of things get into personal preferences too.
I come from so long ago that a lot of what I prefer comes from the way I did it during my formative years.
I like to get my sound on stage primarily from my amp ..... I like to hear it coming from back there with no horn popping out that top end which you have in a monitor. I like just a touch of git in the monitors IF anyone else wants it.
I also like to get a certain amount of my out-front sound from my amp too because I'm always wary of letting a soundman have complete control of my sound unless I know him.
Yes, I've played thru very many nice PA/Monitor set ups where it sounded great but I've played just as many or even more where it didn't.
If I use the same process every gig then I can get the same sound every gig which is my goal. If my git always sounds right ..... then I don't have to think about that at all and can play better. So, to me, the only way I can make sure it's the way I want it is to be in control of it.

Having said that, there are plenty of great musicians that get great results from the 'small-amp thru PA' set-up. It's just not my preference.

 

[EZchair Pickin]

I was watching videos on youtube on a vox ac30 and it got to a part on the biasing of the amp. It said something along the lines of putting the bias hotter gives you more clean headroom.

The AC30 custom classics have a switch on the back to go from 22 watts to 33 watts. This is what they are refering to in the video. At 33 watts, there is more clean headroom available. I'm sure that the bias must change somehow, but I'm not sure why they describe that feature as rebiasing the amp instead of just calling it a selectable power output switch or something along those lines. I agree that is kind of confusing and misleading to hear vox talk about it though.

 

[dementedchord]

it's been yrs since i've worked one one of these and cant say i remember much about it... the only schemo i have of it is in the aspen pittman book and it shows an adjustable bias useing what in the schemo is designated vr3...