Which Choke for jtm45/100

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Which Choke for jtm45/100

Postby Ydna » Sat Feb 12, 2011 4:56 pm

I'm going to be building a Dickinson(Hendrix) spec jtm45/100 soon, and I'd like to know, what choke would be better, the 20H choke or the 3H choke.

And I'm planning on using the PT that can do 560v on the plates, and I was wondering how well will Gold Lion KT66s take that? I've heard they can, someone on metroamp has had their amp at 535v and the tubes have been good for a two years.
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Re: Which Choke for jtm45/100

Postby Roe » Thu Feb 17, 2011 6:35 pm

its a matter of taste. the 20h will lead to slightly lower screens voltage thought
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Re: Which Choke for jtm45/100

Postby Brian Wallace » Thu Feb 17, 2011 9:41 pm

The early 45/100 amps had 3H and 20H chokes in them. I see it as a matter of taste as well. I think the 3H has a nice open tone to it and it allows the amp to break up nicely while the 20H will tighten the amp up and keep it a bit cleaner.

As for the tubes, I have a 45/100 here I built with 560 on a quad of VA KT66's and it runs fine. Of course tubes vary and this can't be said for every VA tube.
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Re: Which Choke for jtm45/100

Postby FredD » Wed Feb 23, 2011 3:18 am

Gee, I was planning on a 3H, but at 490 plate voltage for today's tubes. I thought all those pre "Black Flag" Super's ran just under 70-100watts?? At least, that's what I'm going for.
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