setting bias on Fender Bandmaster

voodooChild · December 16th, 2003, 07:02 AM

Hi. I was just wondering if anybody knew of any websites or books that could walk a newb through setting the bias on a '69 (I think) Bandmaster Reverb. It's in dire need of new power tubes. The volume starts to fade and it starts clipping way early after its been on for about 1/2 an hour. Anyway, I think it has the original tubes in it and I'm considering JJ's (6L6GC) as a replacement. Also, how can you tell when a rectifier tube starts to go? Thanks in advance, this forum is great.

Wally · December 16th, 2003, 07:36 PM

Voodoo, I am going to guess that given the age of that amp and the fact that you think it has original tubes that your amp is in need of some servicing. In particular, I would guess that the electrolytic capacitors need replacing. After that job is done, then one can worry about tubes and biasing.

AtomicMassUnit · December 21st, 2003, 02:11 PM

You'll probably need to convert that amp to a level bias. If you're going to be working on amps, be sure you know safety procedures. There's a lot of information on Ampage at www.firebottle.com to get you started, but you could also just bring your amp to your local tech. It keeps them in business. If you are going to do it yourself and need any information, you can email me at xxvassagoxx@hotmail.com

Atomic

December 16th, 2003, 07:02 AM	#1 (permalink)
voodooChild NEW MEMBER! Join Date: Dec 2003 Location: Cookeville, TN Posts: 2	setting bias on Fender Bandmaster Hi. I was just wondering if anybody knew of any websites or books that could walk a newb through setting the bias on a '69 (I think) Bandmaster Reverb. It's in dire need of new power tubes. The volume starts to fade and it starts clipping way early after its been on for about 1/2 an hour. Anyway, I think it has the original tubes in it and I'm considering JJ's (6L6GC) as a replacement. Also, how can you tell when a rectifier tube starts to go? Thanks in advance, this forum is great.

December 16th, 2003, 07:36 PM	#2 (permalink)
Wally Friend of Leo's Join Date: Mar 2003 Location: Lubbock, TX Posts: 4,225	Voodoo, I am going to guess that given the age of that amp and the fact that you think it has original tubes that your amp is in need of some servicing. In particular, I would guess that the electrolytic capacitors need replacing. After that job is done, then one can worry about tubes and biasing.

December 21st, 2003, 02:11 PM	#3 (permalink)
AtomicMassUnit Tele-Meister Join Date: Apr 2003 Posts: 153	You'll probably need to convert that amp to a level bias. If you're going to be working on amps, be sure you know safety procedures. There's a lot of information on Ampage at www.firebottle.com to get you started, but you could also just bring your amp to your local tech. It keeps them in business. If you are going to do it yourself and need any information, you can email me at xxvassagoxx@hotmail.com Atomic