About biasing tube guitar amplifiers

[vintagekiki]

Links in this thread is for advanced users and his purpose is strictly for educational use only.
Proper high-voltage safety procedures and precautions must be practiced at all times when biasing vacuum tube amplifiers.
This is a dangerous setup and SHOULD ONLY BE DONE BY EXPERIENCED TECHNICIANS.
Vacuum tube equipment operates on very high voltages. 350-450 volts or more can be found inside a typical tube guitar amplifier. THESE ARE LETHAL VOLTAGES. Do not attempt to disassemble, repair, or modify any vacuum tube equipment unless you are qualified to do so.
Keep that tube amps use high voltages, and they can *KILL* you if you don't know what you're doing. So, if in doubt, leave the job to a qualified technician.

CAREFULLY READ every WARNING, every DISCLAIMER, every CAUTION in EVERY DOCUMENT.

IF YOU'RE NOT *SURE* WHAT TO DOING, *DON'T* DO IT!!
==============================================

http://aga.rru.com/TechTips/disp.cgi?file=LV/BiasAdj.tt
http://aga.rru.com/TechTips/disp.cgi.../DslTslBias.tt / Bias DSL&TSL Amps
http://marstran.com/50W%20Bias.htm
http://tone-lizard.com/Biasing.htm
http://www.aikenamps.com/BackBiasing.html
http://www.aikenamps.com/Biasing.html
http://www.aikenamps.com/CrossoverNotchBiasing.html
http://www.aikenamps.com/WhatIsBiasing.htm
http://www.aikenamps.com/Why70percent.html
http://www.amp-fix.com/biasing.htm
http://www.amp-head.com/faq.php
http://www.angelfire.com/electronic/...y/Biasing.html
http://www.blueshottub.com/biasexplained.html
http://www.classictubeamps.com/BiasSupply.html
http://www.diyguitaramp.com/bias.html
http://www.diyguitarist.com/GuitarAmps/PT-Biasing.htm
http://www.duncanamps.com/technical/lvbias.html
http://www.gearo.com/Files/5150biasmod.pdf
http://www.glass-ware.com/tubecircui...o_Biasing.html / see More at bottom
http://www.harpamps.com/micKcircuits/Biasing.html
http://www.jt30.com/jt30page/micKcircuits/Biasing.html
http://www.lynx.bc.ca/~jc/bias.html
http://www.mesaboogie.com/US/Smith/biasadjust.html
http://www.realhi-fi.com/biasingyouramp.html
http://www.regiscoyne.com/tech/bias
http://www.svvintageamps.com/tubebias.php
http://www.tubedepot.com/whisbipo.html
http://www.ampwares.com/bias.html
http://www.lynx.bc.ca/~jc/fenderBiasChange.html

Bias Calculator
http://www.webervst.com/tubes/calcbias.htm

How to Change Tubes on Vacuum Tube Amplifiers and biasing from AOL Video
http://video.aol.com/video-detail/ho...ier/2361572081 / Safety Tips for Changing Tubes on an Amplifier
http://video.aol.com/video-detail/ho...ier/1396772449 / How to Remove Power Tubes on an Amplifier
http://video.aol.com/video-detail/ho...ubes/750710428 / How to Install Power Amp Tubes

http://video.aol.com/video-detail/ho...mps/1698228959 / What is Biasing in Tube Amps?
http://video.aol.com/video-detail/ho...ier/1764946758 / How to Set Bias for Left Power Tube of Amplifier
http://video.aol.com/video-detail/ho...ier/2590414462 / How to Set Bias for Right Power Tube of Amplifier

more?
http://video.aol.com/video-search/qu...e%20Amplifiers

[Bruce / Mission Amps]

And, if you have some extra cash, here is a link to one of the best and most useful bias testing gear I've ever used:

http://www.compu-bias.com/

[Enzo]

That looks interesting. I like that you can wave it under the customer's nose when he asks if you "biased" the amp right or not.

[Alex R]

That looks interesting. I like that you can wave it under the customer's nose when he asks if you "biased" the amp right or not.

Yeah, have a read through these and tell what kind of bias it was you wanted.

He'll come back and say 'brown and creamy'.

[TD_Madden]

I usually use a Bias-Rite/multimeter for the current, another multimeter for the plate-voltage, and a cheap calculator for wattage.

[TD_Madden]

I notice the Compu-Bias has "typical AB1 tube bias" on the face of the device.....

8-13 watts for a 6L6 sure seems low!

[DirtyGeorge]

The list also has 6L6GC a little further down.

[TD_Madden]

Thanks for pointing that out!

[Celluloid Hero]

Hey all, saw my link on this page and thought I'd put in my 2 cents. I think this link is worth checking out : http://tone-lizard.com/Biasing.htm because it presents info that is contrary to what some say, and it's always good to hear contrary opinions. I usually use the transformer shunt method to bias my amps, but I admit that I wasted a PT once because I wasn't being carefull, and I also got a jolt of the B+ once which made me scream and throw my guitar across the room for the same reason. : )

Kiki, thanks for the link, I am honored to be on a list that includes Aiken, Brian Wallace, and that Bruce collins responds to. What do you think of my site?

Ryan

[Dave Curtis, dB AudioTech]

I usually use a Bias-Rite/multimeter for the current, another multimeter for the plate-voltage, and a cheap calculator for wattage.

I use a Fluke 8060A and a TI-35II.

[vintagekiki]

About biasing

http://www.aikenamps.com/index.php/what-is-biasing
http://www.aikenamps.com/index.php/idle-current-biasing-why-70-percent
http://www.aikenamps.com/index.php/the-last-word-on-biasing
http://www.aikenamps.com/index.php/what-is-back-biasing
http://tone-lizard.com/biasing/
http://web.archive.org/web/20121118023641/http://www.diyguitarist.com/GuitarAmps/PT-Biasing.htm
http://web.archive.org/web/20140211062431/http://www.lynx.bc.ca/~jc/bias.html
http://web.archive.org/web/20120327172109/http://www.mesaboogie.com/US/Smith/biasadjust.html
http://web.archive.org/web/20080511144715/http://www.ampwares.com/bias.html

Bias Calculator

http://www.tedweber.com/webervst/tubes1/calcbias.htm
https://www.amplifiedparts.com/tech-articles/tube-amplifier-bias-calculator
https://www.grangeramp.com/bias_cal.php
http://ax84.com/biascalc.html
https://www.easycalculation.com/engineering/electrical/bias-calculator.php
http://www.mh-audio.nl/Calculators/TBias.asp
http://www.rogb.dk/tools/bias.html

[m1989jmp]

I'll just add that there's a really neat tool for browsing long-gone pages, probably a lot of these links don't work anymore.

http://web.archive.org/

[Dave Curtis, dB AudioTech]

Hey, this is better than Facebook memories...
Haha!

[g1]

Hey, this is better than Facebook memories...
Haha!

It's been quite a while Dave, good to see you here!

[vintagekiki]

https://www.scribd.com/doc/219396921/Valve-Biasing

https://www.scribd.com/document/128702505/riverra-biasing-docx

https://www.scribd.com/document/80416864/Biasing-Cathode-Biased-Amps

https://www.scribd.com/doc/75567956/How-to-Bias-a-Guitar-Tube-Amplifier