high gain pre, heater elevation, humdinger, and DC

[middlec]

tl;dr
ultra-high gain guitar preamp. Heater supply, 1st stage. Which one(s) would you do?
a) DC supply
b) humdinger
c) heater elevation

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I'm building a preamp, focused entirely on heavy metal using 4 ECC83 gain stages. From Merlin's (aka valve wizard) design book, the suggestion is to have the 1st gain stage use a DC heater.

Earlier in the book, under noise, he shows this with a humdinger. And if I'm already doing that, why not elevate it, it's just two more resistors and a cap.

Doing all three seems overkill. I mean I could, but...

 

[baudouin0]

For high gain guitar amp definitely a) DC. If your using ECC83 DC on first and second.


Really good book on this:


Designing Valve Preamps for Guitar and Bass, Second Edition

 

[petertub]

tl;dr
ultra-high gain guitar preamp. Heater supply, 1st stage. Which one(s) would you do?
a) DC supply
b) humdinger
c) heater elevation

---

I'm building a preamp, focused entirely on heavy metal using 4 ECC83 gain stages. From Merlin's (aka valve wizard) design book, the suggestion is to have the 1st gain stage use a DC heater.

Earlier in the book, under noise, he shows this with a humdinger. And if I'm already doing that, why not elevate it, it's just two more resistors and a cap.

Doing all three seems overkill. I mean I could, but...

They are used in different environemnts:
-DC filaments , best, provided the DC is good
- humdingers - used when AC is used for filement to "nullify" remaining hum
- raised filement - used when a cathode is at DC level above some arbitrary

level ( 75Volt ?) . but not to have elevated filaments on other tubes where
cathode is close to ground. This usually means that one needs several filement
windings