I also have one, and have heard Bob Levi's E.A.R. 912 Dave Weinharts E.A.R. 912 at his shop when I brought in a pair of speakers to demo for him.
Like you I also bought it for the phono stage, and remote, and the fact it can drive multiple outputs at once.
Wadia 860x With Great Northern Sound Statement upgrade
Goldmund Studio Turntable with T3-f arm
Mixer (see below)
Power: MIT Z-powerbar cryroed.
Living room System 1
Balanced output 1 from the EAR 912 front end
Home Theater signal from MSB Analog DAC and UMT+ with all separate power supplies
MIT MA-X SHD 110
VAC PHI 200
MIT Oracle SHD 120 speaker cable
Chapman T-9MKII Speakers
Living room system 2
gets single ended RCA signal from E.A.R. 912
Infinity RS1 Electronic crossover
Audio Research D-250MKII SERVO with Great Northern Sound Upgrade (High frequency panels) 250 w.p.c.
Odyssey Audio Kismet Extreme Monoblocks 200 w.pc.
MIT reference cable.
Infinity Reference Standard RS1-b
Entec SW-1 Subwoofers one pair flanking the Infinity RS-1b
gets single ended RCA signal from Wadia 860x
Audioquest Lapis interconnect
Audio Research VS-110 with Sveltland 6550 winged C tubes 100 w.p.c
Nordost White Lighting speaker cable
Magnaplanar Tympany IV-a
gets signal from E.A.R. 912 (tape out loop)
Scott 299b integrated tube amp (GE 7581) 20 w.p.c.
Analysis plus 12 gauge Oval speaker wire
Chapman T-7 speakers Dual Isolation cabinets
gets signal from E.A.R. 912 balanced output 2
Bozak Mixer (on order) (which can feed everything through the EAR 912)
(2) Technics 1200 MKII
Vestax VCI 100 controller with EAN Golden Arcade Mod v3
Hegel HD25 DAC or Wadia 860x
Wireworld Oasis 7 XLR
Genelec s30D tri-amped powered 360 watt ribbon monitors (these come alive fed by the EAR 912 an amazing combo)
Generic Toslink cable
Aqua La Voce NOS DAC
Nordost Red Dawn Interconnect
Sherwood S5500II (JAN Phillips 12AX7WA, GE 7868) 35 w.p.c.
Chapman T-8 speakers
So that EAR 912 is so versatile, it's ideal for this sort of thing. It's grounding scheme is so great. zero hum.
The point of posting all of this is to note that the EAR 912 sounds good in every system- and remarkably helpful to an unexpected degree in the Genelecs which I did not care for (in terms of audiophile consideration) prior to adding the EAR 912 and now they are one of my top 3 favorites...(but only fed by the EAR 912 through the analog input of the GENELEC s30D).
So rolling tubes in it is a bit tricky. Since all systems sound a bit different. I haven't sorted it all out yet. The Infinity RS1b system is the one I am focusing on the most.
I replaced the two line stage 6DJ8 with Amperex 6922 and also the middle one of the phono section with another Amperex 6922
I have a VALVO ECC88, and another tube Brimar ECC88 to try rolling into it. Also Dan the EAR contact for the USA offered to help me with tube rolling.
I probably will try a few Mullards too. My guess is that British tubes were probably what Tim de Paravincini had on hand when he made the pre-amp..so maybe he used British tubes for his own rolling.. if he does that...just a guess, no more.
He did stop in my room at the recent Newport Show, everyone feels like an audio neophyte around the guy, I think he has it right, and the rest of the industry is wondering how one guy can make so many good products on so many levels...and lets not forget I think is well into his 70's and to see him hopping up and down making his point takes away my fears of getting older...fantastically great guy and willing to teaching share, when I am sure most would have lost their patience decades ago.
I'll keep you posted... Did you find anything particularly good? I have not tried a 7DJ8 or 7308s...