Bias modification to my Mesa Boogie

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beasleybodyshop
Posts: 1089
Joined: Tue Jul 02, 2013 12:51 am
Location: East Texas (Yee Yee!)

Re: Bias modification to my Mesa Boogie

Post by beasleybodyshop »

Thanks Phil, i finally found a good combination that works. 15K in series with the wiper, one leg continues on to the tubes, other lug has 100K.

Plates voltage is right at 460, so for a set of 6L6GCs that puts her right about 45-46ma? Thats about where she sits now.
"It's like what Lenin said... you look for the person who will benefit, and, uh, uh..."
vibratoking
Posts: 2640
Joined: Tue Nov 10, 2009 9:55 pm
Location: Colorado Springs, CO

Re: Bias modification to my Mesa Boogie

Post by vibratoking »

That setup sounds odd. I think you should have the pot setup as a variable resistor with the wiper tied to the bottom of the pot. I am guessing that something is not quite right?

Care to post a small schematic of what you did?

After looking again, I don't think the Mesa schematic is accurate. I attached a schematic of what I would do. Of course, you could scale things to draw less current or adjust the voltage range.
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beasleybodyshop
Posts: 1089
Joined: Tue Jul 02, 2013 12:51 am
Location: East Texas (Yee Yee!)

Re: Bias modification to my Mesa Boogie

Post by beasleybodyshop »

Thanks i will look it over
"It's like what Lenin said... you look for the person who will benefit, and, uh, uh..."
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