Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Ed_Chambley on April 06, 2012, 01:51:30 pm
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I am going to use this layout, but I put bias controls on the back with probes. What do you think would be the best setup. To separate into dual bias, or a bias/balance? NOS 6v6 singles are cheap. I will have a 50v bias tap PT.
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NOS 6v6 singles are cheap.
:w2: Where?
Less than 6L6's or EL34's, but still..... Ed did you win the lottery and not tell us???? :laugh:
I like the idea of dual bias, but it can be a pain to work it in space wise.
Edit; just saw you wrote singles, sorry.
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Either dual or balance is fine. Depends on if you want them independent of each other.
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I prefer bias + balance - it's easier to dial-in the right voltage - but dual bias pots are OK.
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I prefer bias + balance - it's easier to dial-in the right voltage - but dual bias pots are OK.
Do you have a schematic of the bias & balance circuit that you like?
Cheers,
Chip
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I prefer bias + balance - it's easier to dial-in the right voltage - but dual bias pots are OK.
Do you have a schematic of the bias & balance circuit that you like?
Cheers,
Chip
No, I do not have a schematic, have you seen one?
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I prefer bias + balance - it's easier to dial-in the right voltage - but dual bias pots are OK.
Do you have a schematic of the bias & balance circuit that you like?
Cheers,
Chip
No, I do not have a schematic, have you seen one?
Kevin O'Connor has one in "The Ultimate Tone" Vol. 1 IIRC but it looks really hard to figure out what the component values need to be.
I've attached one that I saved in 2010 based on this thread:
http://www.el34world.com/Forum/index.php?topic=8863.0 (http://www.el34world.com/Forum/index.php?topic=8863.0)
Note that FYL offered up a circuit there, so he responded to my request before I asked! Actually, I ought to bookmark that thread so I can find it again when I want it. Elegant French is just so... elegant!
Cheers,
Chip
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In reviewing the schematic, it shows creating adjustable bias, the balance from the PT voltage. If you had a bias tap of 50v and were using 6v6, would the wiring be the same except you would not need the 120K resistor? What else would need revised. I am assuming the pots are connected center lug to center lug.