The only pure Direct Heated Triode phono preamp I do know so far is the H 5000 Allnic. Allnic is greatful to Mr. G.W. ELMEN of Western Electric for inventing Permalloy for transformer core use, and in so doing, providing an enormous service to recorded music listeners.
Using my two tonearms by just switching one of the two input buttons on the front panel of the H 5000 (MM, MC) the DHT phono pre is one of the instruments providing extremely low noise reproduction. The unorthodox arrangement of the two units in my system is part of the large, bulky and weak construction, DHT tubes tend to vibrate with their tiniest external stimuli. Avoiding as much confrontation as possible with direct sound parameters both units are pretty good taken out of the stream. The DHT tubes only get hand warm.
Having had some weeks of experience I really believe this is one of my favourite phono pres, no noise just playing music in the way I love it. You may be happy owning this piece of excellence in your phono chain.