6505/5150 bias mod

[jamesy_pwd]

hi, ive currently got my amp in at the tech getting 1) bias mod 2) master volume number 3 is a surprise, hehe, anyway, i was just wondering, what are the major benefits of the bias mod, like how much does it increase awesomeness of the sound? better bottom end? warmer? all of the above? im getting the power tubes biased to 50mA

 

[petereanima]

im getting the power tubes biased to 50mA

50mA per pair i suggest?

the benefits of a Bias-Mod is, that now your tubes will work how they are supposed to do! less high end fizz and a warmer sound are the main-benefits, it will also be a bit more dynamic and clean sound will improve also a bit.

 

[sami]

bias mod definitely makes it warmer. I highly recommend it. Mine was home done, not by FJA. I wish I coulda sent it to him because I would've had other work done as well. I just didn't want to ship it from TX to new england and back.

 

[155]

50 ma that sounds way high for those , no?

 

[kazE]

I just didn't want to ship it from TX to new england and back.

FJA is located in upstate NY. Am I missing something? haha.


What exactly is the benefit of having a master volume installed on a Peavey?

 

[7 Dying Trees]

I biased a 5150 to 42mA a while ago when i did my bias mod, it was a bit too hot, you should be looking at 37mA ish, best thing to do is look at the eurotubes website.

Basically, bias it too hot, and the tubes will redplate. You don't get much out of biasing hot other than vastly shortening the life of your power tubes. That is, unless, you are using other tubes that 6l6's, ie, you've done something fairly awesome like kt88's or 6550's...

 

[7 Dying Trees]

FJA is located in upstate NY. Am I missing something? haha.


What exactly is the benefit of having a master volume installed on a Peavey?

The post controls control the FX loop volume, and the overall volume. A master volume will allow the channels to be balanced, hit any FX loop devices hard enough (ie, a good amount of signal) (like noise gates where you only really want to set the threshold once), and then allow for the overall volume of the amp to be controlled without high post values turning it into a permanent weapon of aural destruction

 

[sami]

FJA is located in upstate NY. Am I missing something? haha.

LOL, naw. Just really early for me and couldn't remember. Plus I'm poor and also couldn't be without it for however long it'd take.

 

[Winspear]

The post controls control the FX loop volume, and the overall volume. A master volume will allow the channels to be balanced, hit any FX loop devices hard enough (ie, a good amount of signal) (like noise gates where you only really want to set the threshold once), and then allow for the overall volume of the amp to be controlled without high post values turning it into a permanent weapon of aural destruction

Interesting, I may consider this, though I was planning to have a volume pedal at the end of my FX loop. Would this work in the same way? I wanted it to basically be a master volume.
Or...could I use speaker cable and put one between the cab and head, or would it get fried?

 

[jamesy_pwd]

I biased a 5150 to 42mA a while ago when i did my bias mod, it was a bit too hot, you should be looking at 37mA ish, best thing to do is look at the eurotubes website.

Basically, bias it too hot, and the tubes will redplate. You don't get much out of biasing hot other than vastly shortening the life of your power tubes. That is, unless, you are using other tubes that 6l6's, ie, you've done something fairly awesome like kt88's or 6550's...

when u got it biased at 42 was that by pair or single or..?

btw to the people wondering im not getting it done at FJA

 

[MaxOfMetal]

FJA is located in upstate NY. Am I missing something? haha.

Ummmm......New York State is in New England.

 

[helly]

For what it's worth, mine's biased hotter than stock by a good bit and I can get heavier tones than a stock 5150's lead channel with my rhythm channel's gain knob at 6-7 and the crunch button on.

And less hiss than on the lead channel.

I recommend it.

 

[sami]

Less hiss by biasing hotter?? The power section's pretty clean, it's the preamp that makes it hiss.