shindo vs. atma-sphere

Hi Tim,

My (deceased) friend,Michael, had already purchased and installed some fairly 'tasty' NOS tubes which he'd purchased from Andy at Vintage Tube Services. Some better than others; all overpriced IMO.

Anyway, the MP-3 linestage takes a pair of 12AU7's And a pair of 6SN7's; and Micheal had/has some dandies. Sylvania and RCA (red base!) 6SN7's, and a range of 12AU7's: Telefunken, Phillips, Raytheon (windmill getter!), Tung Sol blackplates, etc. I guess I like the RCA 6SN7's and the Telefunken 12AU7's best so far; but they all sound great.

The phonostage takes 3 pairs (gainstages) of 12AT7's plus one more 12AT7 which is a 'constant current' modulator (not in the signal path). I have become addicted to the GEC A2900, or its military version CV6091 (same tube.) I use them everywhere I need a 12AT7: 7 in the MP-3, 2 in my headphone amp, and four in my MC275 (McIntosh) amp. They now cost (minimum) $125 each! They have great sonics, but more important, they have the highest transconductance (a measure of a tube's gain, or 'strength') of any 12AT7. As such, they provide the best signal to noise ratio in situations like the 3 gainstages in the MP-3 phonostage -- which is what makes it actually possible to use the MP-3 with a .6mv MC cartridge and without any SUT! In my power amplifier, the 12AT7's are drivers for the KT88's, and if you use any of the four strongest KT88's as I do (EAT, GEC, Psvane, Shuguang) then this is the only driver strong enough to accurately control the grid voltage in those ultra-high-power tubes and get the best (cleanest) bass out of them. (Those four tubes all have transconductance values of 12,000 micromnhos. Every other KT88 out there is 7500 or less - usually 4500 -5500 ;~)
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For the differences between the MP-3 and MP-1 preamps, the best place to start is the Atma-Sphere website, as well as discussions and reviews.

I can tell you though that the MP-3 is not a 'baby' MP-1. They both use balanced differential circuits but different tubes. And the MP-1 is a two chassis unit (with a separate power supply.) It's also about 3x or 4x the price of the MP-3 ;~)

Capacitor upgrades are generally a good idea. Whether V-Caps are the preferred upgrade, I don't know. Capacitors are like tubes - they are to taste ;~) Ralph thinks Chris Van Hul's V-caps are special; a lot of other people like other caps better . . .

Caddock resistors can provide a warmer, smoother sound, but to hear any difference, you have to change ALL OF THEM!
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Thanks everyone for your responses. They have all been a big help.

Odds are I would get the MP3, not just for cost but also for space considerations. But the Shindo sounds awfully good too.

If you want to hear the difference brought by resistors, get a variety of pairs and try them in the phono load position on the backside of the preamp (at least on the MP-1, I assume a similar spot for the MP-3). They are simple to swap and the gear is so revealing that yes a single resistor's difference in each channel is audible. Audio Note Tantalums, nude Vishays, Caddocks, for example.

That's a nice lot of tubes to play with. For me, finding quiet 12AT7s was challenging. Some of my favorites are the Sylvania GB-6201 and the Siemens 12AT7. Ken-Rad and Sylvania for the 6SN7s, RCAs too. Among caps I had the CuTF version of the v-Caps installed and definitely found the upgrade worthwhile vs. stock. Andy at VTS is a great source for 6SN7s.

I have a high-performance DIY unbalanced line stage with single 5842 RF tube p/c > Magnequest output transformers (tube rectified OPS.)  My 5842 outperformed a highly regarded commercial 300B preamp and ditto a 6SN7 preamp. 

Yesterday I finally AB tested my 5842 vs. $4500 Atma-Sphere MP-3 line stage only w/V-Cap upgrade ($600 SRP IIRC.)  

The rest of the system is superb, as follows: Huge custom server/streamer built summer of 2021 has 4x the power of Chord's M-Scaler and more power than a $30k Extreme player; running HQ Player's most advanced filters/algorithms (separate outboard NUC runs Room library function only) > Holo Audio May KTE3 DAC > preamp > Atma-Sphere's class D mono blocks (ETA this month) > AudioKinesis Gina satellite w/AudioKinesis Space Generator reverberant field accessory speakers.  Two kilo-watt sub amps > four AudioKinesies subs in a distributed array.  All Clarity Cable.  

MP-3 outperformed my 5842 in every way. Bass clarity was improved a lot as was the nuance and illusion of a human being playing an electric bass.  The program was live, starting with just bass, electric piano and maybe some percussion. The size of the venue went from largish on my 5842 to sounding like it was outdoors; the walls and ceiling of my room seemed to disappear.  Detail, clarity and transparency improved with more of see-through effect; the presentation more closely mimicked big electrostatic panels.  Image separation improved as did the space between the images. The stage and images appeared to form a large, natural and beautiful arc from a center seat row 3 to 5.  The music had more swing, verve and emotional connection, that effect that makes you savor to the last and final silence.  

I was prepared for my 5842 to outperform the MP-3; no dice!     

The MP-3 is a world class preamp IME.