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Atma-Sphere MP1 with single-ended inputs and outputs? Adapters OK?

I had the opportunity to hear an end-game system (for me) that was fronted by an Atma-Sphere MP1 preamp and their Novacrons.  I was blown away by the overall sound, and am highly considering starting purchases toward that system for myself, but had the following questions I'm hoping someone could answer.

In short, the purchase path for me is likely going to last 18-36 months, given the costs of the various components and speakers, so I'm going to have to be living with "hybrid" systems for that time period while I spread the purchases out.

My current weakest link is my pre-amp (although it's not weak, but...).  If I start with the MP1, both my source material (VPI Classic turntable) and amps (Thoress 845 SET monos) are single-ended.  I'm sure I could get an appropriate balanced output for the VPI (I think?) and my DAC already has balanced out (which is my only other source), but what loss in sound quality will I experience adapting for singled ended RCA connections out from the MP-1 to my SET monos?  My current set-up has short (1.5M) runs, so the length of cable won't be an issue for me in single-ended.  But will using something like adapters or the tape outs on the MP1 negate any sonic benefits of the MP1 I might otherwise be getting for the time period I'll be using single-ended amps?  BTW, I LOVE the Thoress 845 amps, so they will likely be the last part of the chain I will consider replacing, and I may choose to keep them in the end-game system depending on the synergy.

Thoughts or experience with the MP1 and single-ended output?
128x128Ag insider logo xs@2xparsons
atmasphere's avatar
atmasphere
11,936 posts
 

@parsons Just a FWIW, any SET can be set up (if you see what I did there 😁) to use both phases of a balanced signal. Its easy to do, inexpensive and does not change the character of the amp. By doing it this way there is no buzz or the like. That is how I have used the MP-1 (or MP-3) with SETs in the past and it works a treat.

The hardest part of this mod is finding a spot on the amplifier chassis to install the XLR connector. The rest of it does not require any component changes in the amp. Normally the SET accepts a signal on the grid of its input tube; but it can accept a signal on the cathode of that tube as well. So we just make that input available on the XLR connector.

runwell
281 posts
 

I got return and refund of the ISO MAX transformer finally.

It has strong noise for my system, I do not know how other's situation.

 

 

 

charles1dad's avatar
charles1dad
10,250 posts
 

@parsons 

I'm also a happy SET amplifier owner. I wonder if your issue is specific to your particular SET. I heard my Coincident Frankenstein 300b SET paired with the Atma-sphere MP-1 and it was splendid! This MP-1 had RCA outputs.  No noise, just very open, transparent, full bodied beautiful sound filling the room.

If I did not already own the superb sounding Coincident Statement Line Stage I could very happily live with the MP-1.

Charles 

parsons's avatar
Ag insider logo xs@2x
parsons OP
149 posts
 

I appreciate all the feedback.

I tried it with 3-4 SET amps actually with unfortunately the same results in each...never had the impact that the all Atma- in balanced provided when being driven single-ended from the MP-1.  Perhaps it was just something with mine if others are having better luck.

I sold my Atma gear last year as the amps were more power than I needed and I found a really strong preamp that complimented the SET amps straight away.

charles1dad's avatar
charles1dad
10,250 posts
 

@parsons 

I'm sure you are thrilled with your Thoress 845 SET,  an excellent sounding amplifier by all accounts.

Charles

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