BIAS testers? which to buy? How the hell do you use them

[KLINKDETROIT]

I have a bunch of different 6L6 and EL34 tubes I want to try out to get my tone. I had a Voodoo mod to my 1999 2 channel dual rectifier. I had an adjustable bias installed and am going to buy a bias tester. First I need to know which bias tester to buy, such as ( SRS OR AMP-HEAD ETC.) and then How to use a dual BIAS tester for a 4 power tube amp. Also, does anyone know the numbers that the screen should read for a quad of Mesa 454 Svetlana 6l6tubes Mesa 430 Russian 6l6 tubes. A quad of SED Svetlana EL34 winged C tubes? and a duet of JJ 6L6GC tubes? I will be using these tubes in matched configuration only in my Mesa dual rectifier with the bold and silicone diode switches engaged. Thanks to anyone that has any info.

 

[Curly]

Re: BIAS testers? which to buy? How the hell do you use them

I'd suggest the one on Weber VSTs site

if money is an issue, then Hoffman amps sells the parts to make a bias probe, but you'll need a multimeter to use with that

 

[Gearjoneser]

Re: BIAS testers? which to buy? How the hell do you use them

I have a mA bias tool I bought off Ebay for $15. With an amp meter, the bias tool and an open chassis plugged into a guitar and cab, I just listen while I look at the numbers. I keep 6L6s around 32 mA and EL-34's around 38mA, depending on where the tone is tightest. I strum the guitar with my left hand and use the miniscrewdriver to make slight tweaks till the amp sounds it's best. I still take note of the numbers to make sure it's not too cold or hot. Before finishing, I move the tool around to other tubes to make sure they're all reading equal, make a few minor tweaks, then put the amp back together after being satisfied that it can't possibly sound better.
If you're extremely careful to NOT touch any internals while the amp is powered up, you should be fine......if you haven't a clue, let a pro do it.