12AU7 SRPP with higher voltage?

Hey Jakob...(or anyone else)

what are the effects of higher voltage with the SRPP stage? say 315v.

reason I ask is, I've added some more filtering caps to the power supply of my EQ. the voltage has risen from 250v to about 315v. This has eliminated the last bit of hum in the system.

I could bring the voltage back down to 250v with some big resistors. But is there any reason to?

THANKS :grin:

Good to know that it´s working nice now. All the wiring inside your EQ is a work of art.

Congratulations!!!

Now let us know how it sounds in the studio.

315 is cool.
You might want to think about biasing up the heater voltage like they do in the LA2 to keep it kosher, cathode stripping and all that bs that nobody cares about.
If the tube gets noisy, microphony and stuff, reduce it back to 250. Thats a big jump just from caps. You must have had a lot of ripple previously.
You can measure ripple cheap and dirty without a scope, just put your meter on ac volts and measure across the dc B+ voltage supply.
cj
Dude, you missed the sound check!

Good to know that it´s working nice now. All the wiring inside your EQ is a work of art.

Click to expand...

Thanks rafafredd, Yea I'm pretty happy with it.

Actually, its 277v at the plates, and about 300v at the rectifier.

Tubes sound good, everything seem fine now.

side note: what I've noticed is the black plate 12au7's have a louder hiss that the grey plates...

so I'll just keep it a little high.

Cj I already sound checked and came back!!!!

277 is perfect!
Dude, you are too good for a sound check!