Other Amps

63 Fender Blonde Bassman Volume Question

76

Finished the Job...the bias caps are now soldered in place and the amp is running perfectly! sounds so much more rich and clear. amazing how such an easy job of replacing all the capacitors can make such a huge difference.

Again, Thank you all so very much for all your help!

Now, onto the ground cable and hopefully Tavo will chime in to talk about bringing the voltage down as stated previously.

I think im going to have to invest in one of his pedals as well...I just cant get that setzer overdrive tone with my Strymon Riverside.

The speakers seem fine to me but I may also change out the stock ones for some vintage celestions and thicken up the speaker cable.

Equipment wise, Im running a Gretsch Hot Rod and that insane 60ft cable. would love to complete the package with the Roland Tape Echo but wow is that little thing expensive!

77

The light sabers just made you 5% cooler :)

Ya if you can solder.. get those astrons out(and realize you'll be using 2 E-caps to replace the duel Astrons on the circuit board), but please please leave the blue molded caps in there. If they are all good, doing their job then you could ask for a better capacitor. Even if you got new blue molded sozos, those caps need near 300hrs of current running through them before they'll ever bloom and give you the dimension of the originals. Oh and for the bias cap, up it to 100uf-100v. When its all done.. lets chat about keeping the amp on 110V instead of 120v. I got one of these Brownie gig masters for my vintage amps.

http://www.amprx.net/upload...

– TheNocturneBrain

sweet! so all is done (kind of) I just saw that you recommended the 100uf bias cap...I just installed the 50umf that the kit supplied...ugh!

78

one last issue regarding the amp...

now that all is said and done, I'm having this incredibly annoying Amp Buzz...the Buzz actually sounds worse coming from the treble knob (as seen in the video).

heres the link:

79

I can't believe I have to ask this again a year later, but did you ever replace the power cable in this amp? That may solve your noise problem, and it will definitely make the amp saver.

The buzz sounds an awful lot like an amp that's biased way too hot. What's the bias set at?

I hate to harp on the same things over and over, but those are like basic amp maintenance, and should be done right away when you buy a vintage amp.

80

I can't believe I have to ask this again a year later, but did you ever replace the power cable in this amp? That may solve your noise problem, and it will definitely make the amp saver.

The buzz sounds an awful lot like an amp that's biased way too hot. What's the bias set at?

I hate to harp on the same things over and over, but those are like basic amp maintenance, and should be done right away when you buy a vintage amp.

– Otter

Sorry man, really haven't had a lot of time this past year for much...and living in miami, its hard to trust anyone with a vintage amp...let alone take the time to look for a reputable amp tech. Im lucky enough that Im a quick learner and I'm good at working with my hands.

So...I did replace that ground cable after that video. The buzz sort of went away...I have to be honest that its not biased. This amp does not have a Bias Pot so even if I had a bias adjusting tool, I couldn't do it. I've also had no luck finding solid info regarding biasing a vintage amp without a bias pot.

all I found out is that these amps have a balance type of bias so that making tube changes did not require biasing. and something about changing out resistors for properly biasing them???

So my next question would be, how the hell do I bias my amp???? even if I did find an amp tech, I still would like to know how to do it myself for future reference and knowledge.

but if my experience in forums serves me correctly...the answer to my question maybe to just install an adjustable bias pot on my amp. This may or may not be the answer but I would like to know regardless.

Thanks

81

but if my experience in forums serves me correctly...the answer to my question maybe to just install an adjustable bias pot on my amp. This may or may not be the answer but I would like to know regardless.

That is correct, you're supposed to install the bias pot. Look at the bias circuit for, say, an AB763 with diode rectifier and 2x 6L6s:

Full Size

I would replace everything in your amp's bias circuit between the transformer and the 220k splitters with the circuit in the Bandmaster. Ignore, of course, the vibrato switch. You can probably reuse some of the original parts, like the diode, because those old metal can diodes in the vintage Fenders look super cool.

82

What an awesome thread!

83

you mean outside the amp? and it just drops down?

– erick lopez

It slides out the back.Once you have the plastic power cord retainer(if there is one) unscrewed and the strap screws out,the chassis will be resting on the cleats.With the back of the amp facing you,reach in with both hands,one on each end,lift slightly and slip it out towards you.


Register Sign in to join the conversation