Less break up from EL84 quad

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Tdale
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Less break up from EL84 quad

Post by Tdale »

If I feel that my quad of EL84 breaks up a bit too much, or give me less clean headroom than I want. will lowering the cathode resistor give me a cleaner sound?

And will lowering the cathode resistor lower or increase the output power?

Tommy
dehughes
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Re: Less break up from EL84 quad

Post by dehughes »

Tdale wrote:If I feel that my quad of EL84 breaks up a bit too much, or give me less clean headroom than I want. will lowering the cathode resistor give me a cleaner sound?

And will lowering the cathode resistor lower or increase the output power?

Tommy
What type of amp are you referring to? There might be other factors to consider...

In my EL84 amp lowering Rk did indeed give the amp more clean headroom, more "power", etc...though it brought about some other issues like too much dissipation, etc... Well worth it, though, IMHO. You could also try some different-rated EL84s....
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Tdale
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Re: Less break up from EL84 quad

Post by Tdale »

Matchless DC30...

Tommy
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Re: Less break up from EL84 quad

Post by dehughes »

Tdale wrote:Matchless DC30...

Tommy
Yeah, with that amp I'd start with the power tubes first and see what you think of that... Then, maybe, mess with Rk, but I think you won't need to once you find the right tubes. 62 ohms is pretty ideal for that setup, IMHO.

Also, those amps are so stinking loud...are you sure you need more headroom? :)
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Tdale
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Re: Less break up from EL84 quad

Post by Tdale »

The guy who bought it (it's a copy I made) would like it to be cleaner at higher volumes than it is now..

What tubes are known to be cleaner?

Tommy
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Re: Less break up from EL84 quad

Post by mlp-mx6 »

If you have a scope, it might be very helpful to find out where in the circuit the distortion is happening. Preamp, PI, power? Otherwise you're just guessing, and either lucky or not.
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Tdale
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Re: Less break up from EL84 quad

Post by Tdale »

I haven't used a scope yet...but I have a friend who has, so I might try him...


Tommy
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