Class A/Triode-based preamps

It depends on the dsign implementation. Heated Triode gear is hard to implement but if the desings eliminate caps in the signal paths then I found most sound better then any other design wth caps in the signal path.

There are very few tube preamps that are NOT triode-based and Class A. See this thread:

http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1270605839

Regards,
-- Al

Hi
BigKidz your observations are spot on in my opinion regarding the absence of signal path capcitors. In my own experience it seems that designs that use DHT and an interstage transfomer in place of a capacitor do seem in general to be more pure and natural in sonic character, by this I mean less of an electronic/mechanical artifact that I now notice with the more common pentode tube/signal cap alternatives. I do realize there are exceptions to this personal observation.

Charles1dad,

I have been working with a buddy how built one and so far it is exceptional. We are now working on adding a transformer attenuator for it.

Triodes are the most linear form of amplification known. Class A operation is also the most linear. So it makes sense that a triode class A circuit will be better, but there are other considerations that affect the outcome!

Atmasphere,
No doubt other factors matter it just seems that the combination of class A, DHT, transformer for interstage and volume control coupled with a large power supply gets the job done. This is the design of my Coincident Statement Linestage and I`m in music heaven as a result.
Regards

I'm curious. Is the volume control before or after the interstage transformer? Is the tube driving the transformer?

Atmasphere,
The owner`manual says signal path follows transformer volume to an input transformer to the 101D tube for gain then to the output transformer.