Tube DIY Asylum

Do It Yourself (DIY) paradise for tube and SET project builders.

Use this form to submit comments directly to the Asylum moderators for this forum. We're particularly interested in truly outstanding posts that might be added to our FAQs.
You may also use this form to provide feedback or to call attention to messages that may be in violation of our content rules.

You must login to use this feature.

Inmate Login

By default, logging in will set a session cookie that disappears when you close your browser. Clicking on the 'Remember my Moniker & Password' below will cause a permanent 'Login Cookie' to be set.

Moniker/Username: The Name that you picked or by default, your email. Forgot Moniker?	Examples "Rapper", "Bob W", "joe@aol.com".
Password:	Forgot Password?
	Remember my Moniker & Password ( What's this?)

If you don't have an Asylum Account, you can create one by clicking Here.

Our privacy policy can be reviewed by clicking Here.

Inmate Comments

From:
Your Email:
Subject:

Message Comments

Original Message

Re: Fuzzy EL34? - Q

Posted by ToobWiz on February 21, 2005 at 18:31:52:
EL34s are not inherently fuzzy, but Class AB is inherently a fuzz box!!! EL34s perform splendidly in a Class A SE circuit, or only a bit less splendidly in a PP Class A design. All this presupposes a really good PSU with choke input. and proper design elsewhere, etc. etc. etc.
The fuzzy ST-70 is very likely from aging of that lousy triode/pentode driver/PI. However, also suspect the caps, esp the coupling caps on the grids of the EL34s. If they are bad, they raise the bias of the output tubes, and boy do you have fuzzy then :-) First off, check the bias on the EL34s and fix that if it is off, then listen. You'll never make it sound good, but you can make sound not terrible :-)
There are 3 rules for good sound:
Class A
Single ended
Choke input PS
:-) :-) :-) :-) :-) :-) :-) :-) :-)
Hey, lookie the smileys, don't flame!!!!
Cheers/Fader
Slogan: "LABOR SVGIT"