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previous: Aron When I read the voltages on my outp... -- 8/27/1999 8:08 AM

Re: More Biasing and Voltages

8/29/1999 4:57 AM
SpeedRacer	Re: More Biasing and Voltages Aron: What kind of tubes are you running again? Basically, you need to take your tube's max dissipation rating (EL34 is 25W for example), and then figure out what wattage you're idling the tubes at.. in your example it's: .034 * 490V = 16.6 Watts (per tube). eg: You're fine.. Of course, you also need to make sure that the B+ is within the ratings of the tube.. obviously 490V would be a real bad time if the amp runs 6V6's etc. 6L6GC's can do 500V ok (above 500V you can get into arcing problems where the plate lead comes into the pinch which is why they made the 6GB6; a 6L6GC with a plate cap). EL34's (real ones, like Mullards) can do 800V on the plate. (!) Not sure I'd try this with the Sino ones if you get my drift. (bring marshmallows!) PS: this is just a quick & dirty answer to a problem that has about as much complexity as any there are (eg: what's the best bias setting?) but this is close enough for rock & roll! If it sounds great and is within the specs of the components, be happy.

8/29/1999 4:57 AM

SpeedRacer

Re: More Biasing and Voltages

Aron: What kind of tubes are you running again?

Basically, you need to take your tube's max dissipation rating (EL34 is 25W for example), and then figure out what wattage you're idling the tubes at..

in your example it's:

.034 * 490V = 16.6 Watts (per tube). eg: You're fine..

Of course, you also need to make sure that the B+ is within the ratings of the tube.. obviously 490V would be a real bad time if the amp runs 6V6's etc. 6L6GC's can do 500V ok (above 500V you can get into arcing problems where the plate lead comes into the pinch which is why they made the 6GB6; a 6L6GC with a plate cap). EL34's (*real* ones, like Mullards) can do 800V on the plate. (!) Not sure I'd try this with the Sino ones if you get my drift. (bring marshmallows!)

PS: this is just a quick & dirty answer to a problem that has about as much complexity as any there are (eg: what's the best bias setting?) but this is close enough for rock & roll! :-)

If it sounds great and is within the specs of the components, be happy.

Replies:

Aron Sylvania 6L6.Thank ... -- 8/29/1999 5:42 AM
Steve A. Speed: &... -- 8/29/1999 8:07 PM
Aron Re: More Biasing and Voltages - lower Plate Voltage??? -- 8/30/1999 7:14 AM