I received my ModWright SWL 9.0 SE linestage back one week ago after upgrade with tube rectified power supply. I find the improvements from the tube rectified power supply to be much as in Dan's statement and findings of folks in another thread.
[Modified to clarify] For most of the time (well over a year) that I have owned the ModWright linestage, I have run Bendix 6900 tubes.
I did not send my Bendix 6900s (or any other tubes) in the unit when returned to Dan for the power supply upgrade. He returned it with two JAN Philips 5687s in the tube sockets. I first removed these and replaced with the original JAN Philips 5687s which were already "broken in" and ran these for two days, then I ran the previously broken in Tung-Sol 5687s (non-cryoed) which I had ordered from Dan within a day of first purchasing the unit over a year ago. I preferred the Tung-Sols (as before) to the JAN Philips. Someone in the "tube-rolling" thread said most folks have "settled on the cryoed TungSol 5687s."
I next inserted the [well broken-in] Bendix 6900s in the ModWright and have used these for the last three days.
To my ears the system synergy using the Bendix 6900s and the tube rectified power supply achieves a significantly increased "gap" over the TungSol 5687s than they did in the stock ModWright SWL 9.0 SE (with other components as described below).
To any who have spent the $500 (plus shipping) for the tube rectified power supply upgrade to your ModWright linestage, I highly recommend trying some Bendix 6900s in it if at all possible.
I hear additional clarity, detail, focus, and frequency extension in bass and treble (beyond the TungSol 5687s). Neutral, tight, and full ... certainly not at all "sterile."
There's no way my ears will let me "go back..."
2-channel system:
Denon-3910 (stock) -> Grover S ICs ->ModWright SWL 9.0SE with tube rectified power supply -> Grover S ICs -> 2 x Odyssey Extreme Monoblock SE (Klaus's "special board" edition) -> Grover S bi-wire speaker cables -> Polk Audio SDA-SRS2 loudspeakers.
All power cords are Black Sand Violet Z1.