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Simple SE Driver or Preamp Tube


2010-12-16 12:45 am
I didn't see this discussed too much in my search.
I have decided to build a Simpe SE amp since it can use a variety of output tubes.

I come from the guitar amp side of things so I am still learning the do's and don't's of audio amps.

I see that the Simple SE uses a 12AT7 driver tube.
That happens to be the one tube I don't have any of.
I have a few vintage 12AX7 and 12AU7 tubes.

I know that the gain level of the 12AT7 is 60 compared to the 100 of the 12AX7.

Have any of you changed the bias of the driver to handle a 12AX7 or does that tube just not work as well there?

Also I see the power tube is not bypassed as in most cathode bypassed amps.
Why is that and what does not having that cap there bring as far as Hi Fi goes?

Thanks, this is going to be a lot of fun.:D