In Reply to: RE: Filament bias and DHTs transformed my system. posted by tube wrangler on August 29, 2012 at 01:04:03:
Hi Dennis,
Maybe the emphasis should not be about meeting God but avoiding the Devil in all his incarnations.
I don't think we'll ever see the end of discussions about how to bias a tube and how to couple stages together. It's pretty basic and unavoidable.
Compromises all the way. There's no decent DHT with a mu over about 15, and I'd even say 10 generally speaking. So that adds stages, no getting round that. I'm sure there are ingenious solutions like solid state hybrid arrangements and in time they'll come out of the woodwork.
Filament bias is probably the worst system except for all the others - like they say about democracy. It's only practical with a few tubes and requires ultra clean DC supplies and quality wirewound resistors. But given that It works like a charm.
Direct coupling is a no-brainer except for the added design problems that throws up. Back to cathode resistors and bypasses. Not a road I'd ever go down unless I was forced kicking and screaming to do so. I tolerate it in my 300b output but only for want of a better solution.
That's it really - everything we do in the end is because we can't think of a better solution and end up with the least bad compromises.
Maybe we should discuss how to build the "least bad" system rather than the best one. I'm sure that's what we all end up doing in practice.
Andy
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Follow Ups
- How to build a "least bad" system! - andy evans 01:21:48 08/29/12 (3)
- RE: How to build a "least bad" system! - Tre' 13:48:03 08/30/12 (1)
- Two words - Glow Ultrapath!! - andy evans 23:24:54 08/30/12 (0)
- RE: How to build a "least bad" system! - drlowmu 06:47:28 08/29/12 (0)