06-09-2013, 01:00 AM
In general, RCA didn't bloat tube counts. Indeed, the D22-1 used all tubes properly. When you wanted superb audio, you used 2A3's for power amplifiers. The D22 was RCA's finest offering in that year, and that was the reason for the Push-Pull Parallel 2A3 power amplifier.
RCA went on in the next year to use volume expander, as on the D22 for phono, and a "High Fidelity Electrola" R99. Vary few of those are known, but I'm lucky to have one. there were other Hi-Fi RCA model phonographs, that used 2A3 power amps. While RCA loved to us 6F6's, they used 2A3's when they got serious about high audio quality.
If you want to see the best example of tube bloat, have a look at the schematic for the Crosley 37 tube set. It's just plain disgusting.
RCA went on in the next year to use volume expander, as on the D22 for phono, and a "High Fidelity Electrola" R99. Vary few of those are known, but I'm lucky to have one. there were other Hi-Fi RCA model phonographs, that used 2A3 power amps. While RCA loved to us 6F6's, they used 2A3's when they got serious about high audio quality.
If you want to see the best example of tube bloat, have a look at the schematic for the Crosley 37 tube set. It's just plain disgusting.
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