The fabulous Walter's Le Pasific RIAA Pre revisited

2nd stage added. It did not sound much impressive when connected to Realistic Disco mixer line in. But when feeding the Sennheiser HD580 headphones directly, jaw droped. Amazing smooth sound. Lucy on vinylengine listening at 3am to Pink Floyd raves about it. Congratulations Mr Hiraga and Mr Walters. Signal path: I've had the time of my life from Dirty Dancing LP - Technics SL1200MK2 - Stanton D6800 EEE-III - Stanton 680 moving iron cantilever cartridge - Le Passific MM RIAA by Walters, derived from Hiraga, one channel - Sennheiser HD580. 4 6V camera type batteries can be used in series inside a Bulgin 2AA battery holder? A fuse in series for protection. It is very low noise too. How would DCC90 triodes compare at such low anode voltage and perhaps open grid for perhaps even less noise or better sound quality? Heaters underhetated a bit or more too for even more detail extraction from magical vinyls. The high Gm model needs perhaps modification?, electron tubes can sound scaringly low noise even at 14 micramperes anode currect especially when open grid, see Pleiades V6 1H4. If more gm is needed then Pleiades bias from anode to grid could be used, but it may not sound less or equally low noise. How would such a fabulous 2SK170 stage sound as a microphone preamplifier? Would an open gate or less drain voltage make it even more low noise, or sounding better? Would an input or output transformer create easier a flat frequency response from producer's brain to listener' brain But back to MM or moving iron or moving coil. Can Le Passific Walters be modified for open gate?