Bare Knuckle Pickups Forum

Forum Ringside => Guitars, Amps and Effects => Topic started by: sgmypod on May 15, 2009, 08:48:04 PM

Title: Fixed bias Vs Cathode biased
Post by: sgmypod on May 15, 2009, 08:48:04 PM

Advantages and disadvantages
(One of my amps is cathode is it worth changing to fixed)

Title: Re: Fixed bias Vs Cathode biased
Post by: Denim n Leather on May 15, 2009, 09:28:44 PM

As long as the amp is biased correctly, it doesn't make any difference to me.

Title: Re: Fixed bias Vs Cathode biased
Post by: shaman on May 16, 2009, 12:24:59 AM

always thought cathode refers to class A-class A doesnt require a "bias supply"...a resistor between ground and power tubes serves as bias ,correct??I am limited on my bias knowledge, but it seems like it may not be necessary due to the nature of class A,whereas AB has that whole push pull thing going on-but I am sure some of the amp gurus will correct me :)..just felt like chimin' in

Title: Re: Fixed bias Vs Cathode biased
Post by: Denim n Leather on May 16, 2009, 03:41:38 AM

You can take a push-pull amplifier and bias it into Class A; I don't think it would sound good, but you can do it. Depends on the specifications on the power tubes in question.

Title: Re: Fixed bias Vs Cathode biased
Post by: Twinfan on May 16, 2009, 09:13:47 AM

I have fixed and cathode biased amps.  I like both types, and fixed may feel a little tighter to play.  So many other things going on between guitars/cabs/valves/speakers though.

The may reason for fixed biasing is to get more power.

Title: Re: Fixed bias Vs Cathode biased
Post by: sgmypod on May 16, 2009, 09:18:55 AM

Am loving the sound at mo in cathode biased....going to try against Horseheads new Bassman when we next practice..to see if I need more power

Title: Re: Fixed bias Vs Cathode biased
Post by: HTH AMPS on May 16, 2009, 10:29:15 AM

I lke the 'feel' of cathode biased amps - the harmonics and lushness of the tone overall are nicer too.

Title: Re: Fixed bias Vs Cathode biased
Post by: sgmypod on May 16, 2009, 10:31:22 AM

those are the bits Ilike...so may stay cathode if it holds it's own

Title: Re: Fixed bias Vs Cathode biased
Post by: Alex on May 16, 2009, 11:14:46 PM

I think this is about Class A amps and, uhm, amps that aren't CLass A.

All I can add is that my Krank Rev Jr - which is self-biasing class A - does definitely have a bit of a different feel to it. You get used to it very quickly though and stop really noticing it.

Title: Re: Fixed bias Vs Cathode biased
Post by: martinw on May 17, 2009, 09:08:00 AM

Class of operation is completely unrelated to bias type.  :wink: