OK... I admit it... I am a dynamics junkie.....

SO I was developing a super low noise version of the standard Devotion for a gentlemen with ALE horns - 110dB/W/m.  Ouch!... but I learned so many things from this exercise.  Several attempts at DC filament supplies left me wanting for tone, until... until I found how to properly isolate the filament from the circuit.  Then the dynamics coming from that black background just stunned me.  I had found a new filament supply. 

Oh, and this is the filament supply that led to the interchangeability of 300B's and 50's...  from the customer:

"Jeff, my pleasure, plus you fully deserve it ; never meant to tell you this, but without being perfect ( some sub optimal speaker binding posts, difficult location for the power cords) your 50 monos are to date the best amplifiers to these ears, and as you know I have a large collection ..."

including, but not limited to: Art Audio, AudioSector, darTZeel, Electronluv, FirstWatt, Kondo Ongaku, Kondo Gakuoh, Korneff, Supratek, Tektron, Yamamoto, Wavelength, etc.

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