Ultra linear vs... not...

[Ralle]

What would a... let's say a Drake-132 sound like if it was ultra-linear?
Is it more lows and highs, plus more eaven in freq levels... hi-fi?

[Ted B]

UL = Hi-Fi, more NFB, less distortion.

In fact, Vox made a small line of UL amps back in the '60s (I once owned one), but they never caught on. In a time when distortion was becoming trendy in pop music, amps that minimized it were a step in the wrong direction.

[Jeff West]

Super Twin, anyone? Marshall Major?

Doesn't fully address your question about guitar amps, but this was the classic influential article for UL in the U.S.:

http://www.keith-snook.info/Articles-fo ... v1951.html

Recommend reading Williamson's 1952 semi "rebuttal" in Wireless World too.

BTW, British tended to prefer "distributed load" to "ultralinear" terminology, like in Mullard and Brimar valve manuals.

Alessandro seems to have made UL work great in guitar amp setting, many would say.

[StuntDouble]

How would a more linear OT reduce the amount of NFB in the NFB loop? I think that's some of what I'm hearing with my current OT, which is partly why 100k on the 4 ohm tap works with this amp, but I'd like to know more about how, or I guess why, the OT affects the NFB loop...interesting.

[Ted B]

I think what you mean is more NFB if the sound is smoother, more bearable with the 100k 4-ohm configuration than expected. I'm not sure that's necessarily what's happening, but if so, it would be interesting. The more I've looked into anecdotal reports, it seems that most feel that particular combination is most compatible with V2 cathode bypass cap(s) omitted, but ...

[StuntDouble]

Sorry...yes, it would be more NFB being introduced into the loop as you would be counter-acting it with less NFB. I think that the fat cap on V2 is balancing out what I hear as a less prominent midranage by adding more mids, even though the character of the mids is rounder and less flat than what I hear with a C1998. It's hard to explain, but that's what I'm hearing so far. I've tried 100k on the 4 ohm tap before, and ther are aspects of it that I liked and some that I definitely did not. It was too fizzy and bright and didn't hold the low-end together well enough. Not so with this OT.