Do You Prefer Class A or AB?

[Edgecrusher]

Re: Do You Prefer Class A or AB?

Heres an article written by mesas randall smith on what class A is.

http://mesaboogie.com/US/Smith/ClassA-WebVersion.htm

 

[Ascension]

Re: Do You Prefer Class A or AB?

My Fender Prosonic has three modes class A tube rec A/B SS rec and AB/Tube rec. In lower volume settings I run the Class A tube most of the time but use the A/B for a tighter bottom as I am able to turn up. Class A REALLY cooks the tubes though. The Power Tube ( 6L6's in this case ) life is about cut in half if you stay in class A all the time.

 

[Lake Placid Blues]

Re: Do You Prefer Class A or AB?

I prefer A/B. I think it makes better use of an amp using a tube rectifier. I think you get a more dynamic and responive sound with a tube rectified amp, if it's A/B.

For higher head room situations, were you would probably be using a SS rectifier; Class A/B probably does high power clean better too.

 

[noth]

Re: Do You Prefer Class A or AB?

I prefer A/B. I think it makes better use of an amp using a tube rectifier. I think you get a more dynamic and responive sound with a tube rectified amp, if it's A/B.

For higher head room situations, were you would probably be using a SS rectifier; Class A/B probably does high power clean better too.

I agree with you, but the reasons may not be what you think. Class A can be incredibly dynamic, and have great solid bass, too. The problem, as I hinted to earlier, is that because the amp is working so much harder all the time, you really have to sink a lot more dollars into the amp to get it to have a power transformer, caps, and output stage stage that will be up to the task of delivering a lot of current all the time. When you do this (and I'm sure most manufacturers don't) Class A sound is hard to beat. But in these switchable amps people are referring to, it's an afterthought, and the amp is "starved" when switched into Class A.

Noth

 

[ImmortalSix]

Re: Do You Prefer Class A or AB?

What's a good example of a good "overbuilt" Class A amp i.e. can run Class A all the time within its design/components?

 

[noth]

Re: Do You Prefer Class A or AB?

What's a good example of a good "overbuilt" Class A amp i.e. can run Class A all the time within its design/components?

That's a great question - I don't even know which guitar amps claim to be Class A - anyone?

Noth

 

[SlyFoxx]

Re: Do You Prefer Class A or AB?

Had this for a while now...sure sounds sweet!

 

[noth]

Re: Do You Prefer Class A or AB?

That Mesa looks like a very impressive amplifier. Seems he thought of everything. Coming from the hi-fi world, I would never have guessed that guitar amps got into things like class of operation. I always thought that price dictated product, so most stuff was down and dirty. I stand corrected.

Noth

 

[Rushfan2112]

Re: Do You Prefer Class A or AB?

I'd argue that many guitarists couldn't tell the difference in a sound test, and maybe even a playing test, between Class A, Class A/B and Class B. I know I can't.

 

[Lewguitar]

Re: Do You Prefer Class A or AB?

I'd argue that many guitarists couldn't tell the difference in a sound test, and maybe even a playing test, between Class A, Class A/B and Class B. I know I can't.

You'd be surprised.

But I think what many think is a Class A amp tone is actually a cathode biased amp tone.

Cathode bias gives an amp a much more touch sensitive tone...you can squeeze the notes out and shape them with your pick and your touch.

Most (all?) class A guitar amps are also cathode bias amps...hence the confusion.

Lew

 

[Dr.Mavashi]

Re: Do You Prefer Class A or AB?

Any great class A or cathode tone in history of metal?

 

[Lewguitar]

Re: Do You Prefer Class A or AB?

Any great class A or cathode tone in history of metal?

I dunno! I can tell you that most Matchless amps are cathode biased amps though. My SC-30 was and my Chieftan is. Lew

 

[noth]

Re: Do You Prefer Class A or AB?

You'd be surprised.

But I think what many think is a Class A amp tone is actually a cathode biased amp tone.

Cathode bias gives an amp a much more touch sensitive tone...you can squeeze the notes out and shape them with your pick and your touch.

Most (all?) class A guitar amps are also cathode bias amps...hence the confusion.

Lew

Good point, Lew. I think I've got the best of both worlds..I building Bruce's 5E3 right now! Can't wait to hear it!:banana:

Noth