SET Asylum

Single Ended Triodes (SETs), the ultimate tube lovers dream.

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Yes - let's define filament bias

Posted by andy evans on September 3, 2017 at 13:06:12:
Filament bias isn't an "attempt to get more power" - that's fixed bias in the old-world sense where it was used for output tubes.

The modern usage is for DHTs, usually but not exclusively in the input section(s). The modern implementation uses sophisticated solid state circuits like Rod Coleman regs (now version 7) and choke input filament supplies. This is not trivial engineering - it's been very well thought out and has a LOT of users around the world.

I'm not particularly surprised you don't understand the sonic benefits since
1. You don't use DHTs in the input section
2. You believe that cathode bypass caps are an acceptable alternative. I don't, and I've tested plenty.

Since you can't do a direct comparison, it's pretty meaningless trying to compare the sonic results.