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tubes with 300B kit

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Hello Ron from Vienna. If I order the new Sophia Princess tube with your ultimate 300B drd kit, does anything need to be changed in the circuit?
What are the sonic differences between ss or tube rect. ??
What are the sonic differences between the 'optional' black gate caps or the standard 'ultimate'.
What etc. between the copper or silver trannies for the above kit.
Silver wire is a small price option so that's OK.
Your kind advice will make purchase easier. To drive Oris/BD3's.
Thanks.

Follow Ups:

Beware - Sophia Princess SET is NOT a 300B! - David McGown 16:13:49 06/16/03 (2)
Mr Wugang of Sophia Electric is doing the community a disservice by trying to promote this tube as compatable with 300B amps. This tube has a plate resistance of 2500 ohms, a mu of around 7 (2x that of a 300B), and a max plate dissipation of only 25W. Although you can modify the amp to *try* the tube out (having the same heater voltage and current, similar B+ and current limits), with 3x the plate resistance, a completely different output transformer should be used for optimum performance. With a 3K transformer of a typical 300B amp, the tube will distort badly at other than low power. $600 is an expensive experiment in my book.
- Well then... - Ron W 16:50:49 06/16/03 (1)
  if your specs are correct, I would say it's not a good tube for use in the DRD amplifiers.
  Ron
  - Re: Well then... - David McGown 17:15:21 06/16/03 (0)
    Ron,
    Also, another reason this would not work for the DRD amp is bias voltage for full output is 24V. For a DC coupled design, this may be a non starter if the current draw through the plate/grid choke drops more than 24V.
    You can check the specs on Sophia Electric's site (http://www.sophiaelectric.com). A friend of mine who is an excellent designer and a former consultant to Sophia Electric confirms the unsuitability of this tube for 300B circuits.
    David
Re: tubes with 300B kit - Ron 12:20:18 06/16/03 (0)
If I order the new Sophia Princess tube with your ultimate 300B drd kit, does anything need to be changed in the circuit?
You would have to ask Sophia if it will work in all 300B circuits. I'm not familiar with the tube.
What are the sonic differences between ss or tube rect. ??
SS has more punch in the bottom end. The tube rect. is slightly warmer in the midrange.
What are the sonic differences between the 'optional' black gate caps or the standard 'ultimate'.
Not much difference in the DRD circuit.

What etc. between the copper or silver trannies for the above kit.
I haven't heard the silver trannies in the DRD yet, so I couldn't comment on the differences you might hear.
Ron

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