Low noise PreAmp "Muon D3a/SE"

Got a idea about preamp, which was based on parafeed µ-metal transformers.
Here you see endstage wired as triode, driving output transformer directly.
Two working modes:
RIAA- front pentode drives selected filter array, then a output tube. Gain about +60,2 dB, which should be fine for MM 5mV
Normal mode- using line input transformer (XLR or Cinch), which drives output tube, filters not engaged. Gain about +10,6 dB
Concept A:
Preferred LED  is 1,5V.   2xLL1545A  2xLL1930  4x D3a
D3a is high quality pentode, framegrid type. High steepness >35000µmho, like JFET.
Triode wired, g2+a.

Concept B:
With Schade type local feedbacks, making C3m pentodes as high gain triodes.

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