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sweept tubes for simple Se recommendation?

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Hi Everyone

I have finished putting together my Simple SE with jj el34s and have been enjoying the sound but now Im keen to try out different tubes without breaking the bank-sweep tubes look very inexpensive but can anyone recommend types that can be used with in the following specs?


POWER TRANSFORMER:
EDCOR 375-0-375 @ 175mA with taps at 50V @ 50mA, 6.3V CT @ 6A and 5V CT @ 3A.

OUTPUT TRANSFORMER:

TRANSENDAR 5K with ul tap


(pics comming soon one I figure out how-does anyone know the code to link to pictures @ filckr etc?)


Thanks everyone (and thanks Tubelab for the great project!):D
 
dubdub said:
sweep tubes look very inexpensive but can anyone recommend types that can be used with in the following specs?

It isn't easy to use horizontal deflection types in single ended circuits. The most linear portion of the characteristic lies well within red plate territory. They work much better in PP, Class AB designs.

The 6BG6 that whitelabrat mentioned is basically an 807 with an octal base, which, in turn, is a 6L6. Other than that one, I'd forget about that.
 
dubdub said:
Hi Everyone

I have finished putting together my Simple SE with jj el34s and have been enjoying the sound but now Im keen to try out different tubes without breaking the bank-sweep tubes look very inexpensive but can anyone recommend types that can be used with in the following specs?


POWER TRANSFORMER:
EDCOR 375-0-375 @ 175mA with taps at 50V @ 50mA, 6.3V CT @ 6A and 5V CT @ 3A.

OUTPUT TRANSFORMER:

TRANSENDAR 5K with ul tap


(pics comming soon one I figure out how-does anyone know the code to link to pictures @ filckr etc?)


Thanks everyone (and thanks Tubelab for the great project!):D


Line-Output bottles dont particularly work well in S.E type designs. For the 'Simple-SE' I would choose a proper audio valve, Loads of types to choose from that wont break the bank!

Sweep/Line-O/P work well in P-P and especially Screen-Drive but nearly all of them suffer from low screen max voltage/dissipation issues when run in S.E modes.....
 
The 6BG6's that WB0SND sells might be the easiest, since he sells adapters to convert them to the 7AC pinout, they were intended to run at 6L6/807 like voltages to begin with, and some Simple SE users already have experience with these tubes. They would probably sound the best, since they really aren't what I consider sweep tubes.

So many sweep tubes are high perveance, meaning they were meant to run at lower plate voltages and higher cathode currents. When you run them at higher voltages, you wind up with large cathode voltages and a lot of heat dissipated in the cathode resistors; you would likely need 100 volt cathode bypass caps, and 10 watt resistors to accomodate sweeps. You also need to accomodate the plate caps, and they may have a different overall gain than traditional audio tubes.

6DQ6 and 6BQ6 have the right pin out (but you still need the plate cap connection) to plug in the Simple SE, but all of the above "gotchas" apply. I am listening to 6BQ6GTB's in my Simple SE right now, but I have a dual secondary voltage power transformer in my amp, making it easier to run the sweeps and little beam tetrodes and power pentodes. I am running the 6BQ6GTB's in triode at about 220 volts and 70 ma / tube, or about 14 watts total dissipation. They don't sound bad, but I consider tubes like these in this application to be kind of a novelty. Somewhere on the site is a pic of my Simple SE with 6DQ6's in it.

George has made some posts on these tubes in the Simple SE, and others probably know more about it than I, but that is my $0.02 worth.

Win W5JAG
 
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