software

thanks in advance

Nothing. A Variac is a device used by Techs to vary the AC current while troble shooting a Amp or formming filter caps. VARI-AC get it? I'm not your brown sounder type, So maybe I'm wrong? But there's a lot of smoke amp; Mirrors
about guy's useing them as part of there rig.

I think EVH ran his amps at above 110v to get part of his quot;brown soundquot;. Not worth blowing an amp up over unless you've got EVH-type money to blow....


Originally Posted by Scott_FI think EVH ran his amps at above 110v to get part of his quot;brown soundquot;. Not worth blowing an amp up over unless you've got EVH-type money to blow....

He actually dropped the voltage down to around 90v. Doing so made the tubes run hotter because the bias was off. That's what has been printed all over the place anyway. I won't argue if I'm wrong though. You can build amps. I just do stompboxes.


Originally Posted by ErikHHe actually dropped the voltage down to around 90v. Doing so made the tubes run hotter because the bias was off. That's what has been printed all over the place anyway. I won't argue if I'm wrong though. You can build amps. I just do stompboxes.

I'm sure you are right as I've never researched the subject. I have never cared what amp EVH used. 90v or 120v, you guys understand what EVH was doing.

If he ran that at 90 just to get the tubes to run hotter, why not just crank up the bias?


Originally Posted by Scott_FI'm sure you are right as I've never researched the subject. I have never cared what amp EVH used. 90v or 120v, you guys understand what EVH was doing.

If he ran that at 90 just to get the tubes to run hotter, why not just crank up the bias?

Easier to plug in a variac than to risk killing yourself with the chasis out. That'd be my guess, and reasoning. I'm not amp tech so that's what I'd do. I have no immediate interest to dig in to my amp at all.

So, does lowering the incoming voltage make the tubes run hotter? That's what I wasn't sure of but it made sense to come to that conclusion since he ran it at 90v and said it made the tubes run hotter.

Posters #2 and #3 are both correct as far the useage of the word. The word has two meanings:

VARIAC is a brand name. In more technical terms...it is an autotransformer. This is the EVH device.

A variac is a generic term for any number of variable AC power supply brands available to electronic technicians for diagnostic purposes.EDIT: I re-read the original post, and I have no idea how it directly relates to speakers.
I read 25 years ago, EVH was using his VARIAC autotransformer to boost the supply voltages to 130VAC. I have no idea if this is correct or not (I just assumed so), but from what I gather, there was a lot of mis-information about the voodoo he used to get his early sound (more power to him!).

newking70...love the avatar! You're gonna put your eye out!!!

Lowering the input voltage doesn't intuitively make the tubes run hotter in my mind. Just the opposite to me.

Either way, the Variac can be quite useful when you want to test out an amp to ship to Europe. It's not like I have 220/240v running out into my shop. Also for powering up an amp the first time, you can start low and raise the voltage up gradually to condition caps (necessity questionable)

Ed used the variac to run the amps at 90-92v. Since he cranked everything on the amp to 10, he used the variac as a means to turn the volume down. He said he cranked up the voltage in one article just to mess with people. He never did that...

Yup, Eddie was so wild/innovative in his earliest Mammoth/VH days that people around him had to tell him to do his soloing with his back to the audience. It has been smart for him to dis-inform the teeming millions/scandalous thousands that would give him nothing in return but more f'n questions.