Rockster tubes

Express, Liverpool, Rocket, Dirty Little Monster, etc.

Moderators: pompeiisneaks, Colossal

Post Reply
User avatar
JoeCon
Posts: 632
Joined: Thu Aug 30, 2012 3:06 pm
Location: Manch-Vegas NH

Rockster tubes

Post by JoeCon »

Guys
A friend has my KT66 Rockster at his place. He wants to know if he can put in a pair of EL34s. It's got 375v on the plates and of course is cathode biased.
Can he just put his tubes in? Will the cathode resistor need to be changed to run the 34s?

Thanks...
In theory, theory is the same as practice. In practice it's different.
User avatar
martin manning
Posts: 14308
Joined: Sun Jul 06, 2008 12:43 am
Location: 39°06' N 84°30' W

Re: Rockster tubes

Post by martin manning »

From data sheet, EL34 cathode resistor for 375V is ~260 ohms/tube, 130 ohms for a pair.
User avatar
JoeCon
Posts: 632
Joined: Thu Aug 30, 2012 3:06 pm
Location: Manch-Vegas NH

Re: Rockster tubes

Post by JoeCon »

Martin
Thanks, there's a 200 ohm in there so he's safe to try them, but they're not gonna be running optimised...
In theory, theory is the same as practice. In practice it's different.
Post Reply