RE: [Harp-L] Re: Fender Pro Jr....

["Joel B. Chappell" <joel.b.chappell@xxxxxxxxxxxxxxx>]

You really can't [make that shouldn't] capriciously swap dual triodes
12AX7,12AU7, 12AT7, 12AY7 etc. around as each type has a different
transconductance curve thus a different plate impendence for each type...
which really suggests that you change some other discrete components else
you may buy some additional distortion... loss of gain etc. Understandably,
I realize the guitar boys want more distortion. In all actuality the 12AY7
has the lowest noise figure. If you were to re-bias the circuit to take
advantage of its gain and run DC on its filaments you would reap some
worth-while benefits, otherwise if your amp has a 12AX7 in the socket, leave
it there. The chap that designed the amp knew what he was doing, at least
back in the day he did.

Joel B. Chappell
21 Billings Street
Milford, NH 03055

-----Original Message-----
From: On Behalf Of Splash!
Subject: Re: [Harp-L] Re: Fender Pro Jr....

You can't have mine.  I'm keeping it.  =8^D
Great little amp.  I tried several vintage tubes of lesser gain in V1 and 
went back to a 12ax7.
Tones deep into my bones!

When life asks you to jump in...
Splash!