In Reply to: SET 300B use 3500 or 5000 Impedance Primary? posted by Neff on February 22, 2008 at 19:06:51:
Neff, hi. That depends is probably the best answer. Does your transformer do both? With 500 V B+ a 1400 Ohm cathode resistor puts the tube in a good area. With a 5K primary it would be possible to substitute Type 50.
A 7.5 V filament transformer can easily be dropped to 5 V - the only change you'll have to make. You could also use a PX-25. 4 V fil? iirc
I bet you'll begin to stop dreaming about 300B so much when you hear a 50. At any rate you'll be able to use either tube. The 300B works just fine into 5K. You may sacrifice a miniscule bit of power but distortion will be lower. Now - if the transformer has a nice big core (30W) you'll be all set (so to speak) for SET bass like you never heard before. Now - if only JJ would produce a Type 50. JJ are you listenin'?
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Follow Ups
- RE: SET 300B use 3500 or 5000 Impedance Primary? - elektron 02/22/0822:56:40 02/22/08 (3)
- RE: SET 300B use 3500 or 5000 Impedance Primary? - Neff 08:56:10 02/23/08 (2)
- RE: SET 300B use 3500 or 5000 Impedance Primary? - danlaudionut 19:24:54 02/23/08 (1)
- What about a 2E22? - andy evans 02:16:21 02/26/08 (0)