Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: tubenit on June 06, 2012, 04:47:41 pm
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I played my Tweed Overdrive Special last night and it sounded really great to me. Nice amp.
Having said that, ................. I was wondering what it would sound like to use a paralleled 12A_7 with a CF instead of the 5879 and a CF.
No other reason, then curiousity & the option to control gain factors thru different 12A_7 tubes.
Anyone tried a paralleled 12A_7 with a CF before ..................... and if so, ........... how did it sound?
The 5879 is in the OD section of the TOS.
with respect, Tubenit
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How about a cascode with the two triodes? I've read that a cascode performs similarly to a pentode.
Cheers,
Chip
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What Chip said. You'd get more gain out of the cascode.
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Thanks for the cascode idea. I would use the 5879 instead of that though.
I was specifically wondering about a paralleled 12A_7 & CF. If anyone has tried that?
With respect, Tubenit
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That 2k2 Rk seems pretty cold for paralled 12ax7s, are you planning on U7 or Y7 or were you going for a cold stage? I'd like to hear clips if you build it. Thanks.
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tubenit - the AX84 "Blues Preamp" has paralleled 12AU7 stages feeding the poweramp. It's possible that someone over on that forum discussed sticking a cathode follower in there while they were developing that circuit.
Sorry for the cascode sidetrack. My initial thought was that it would allow you to substitute different 12A_7 tubes for different gain levels, but I doubt a "universal" cascode circuit would be very useful.
With respect,
Chip