Though I have three Mobile Fidelity Ultradisc One Step 45 RPM sets (Santana Abraxis, Marvin Gaye What's Going On and Crosby Stills and Nash), I was not able to participate in the class action suit as I live in the UK. I wanted to participate as I always felt that digital processing of vinyl resulted in recordings that were inferior in that the artificial analogue did not sound as real as real analogue. A recent test I ran however, both supports this view and also doesn't.
I tested two of the above Mobile Fidelity Ultradisc's above (Marvin Gaye and CSN) against the best analogue "One steps or equivalent" that I could find.
From Deutsche Grammophon, der offizielle shop (where I had been sourcing The Original Source records) I bought a "Mastercut Record" (actually produced by Supersense in Austria) "hand-cut" acrylic/lacquer of Marvin Gaye (What's Going On), released on 31 Oct 2023.
From The Electric Recording Company I was able to secure a pure analogue from the master tape (copy no. 297/450) of Crosby Stills & Nash, also just released from orders taken last month.
I had three fellow enthusiasts join me for the Marvin Gaye comparison. First we listened to side one of the "hand-cut" Supersense acrylic at 33.3 RPM. I then turned down my amplifier two notches so that the MoFi (which is recorded louder) would be more or less the same volume, and set the speed to 45RPM. I played the first two songs (all of side one). Thereafter I asked each listener whether they preferred the first, the second, or both the same and why. The first listener, who listens to digital predominately, preferred the MoFi because the voice was clearer, instruments more distinct as well, more hi fi and what he would play to a potential buyer if I wanted to sell my stereo. The second listener, who also plays mostly digital currently, preferred the pure analogue acetate, saying it was more real sounding. The third listener, plays analogue records, thought that the digital-to-vinyl MoFi would sound terrific on his system and the difference wouldn't be perceptible, however he said on my system that the acetate definitely sounded better, more air around the instruments and singers, more relaxed listening to it. I too felt that the acetate sounded much better, that with the MoFi you were drawn to the various hi-fi aspects of the sound reproduction, that the voice and instruments sounded etched, almost harsh and that I would want to turn off my stereo after listening to a side or two at most, whereas with the pure analogue acetate, I could just relax and get lost in the music.
The CSN comparison was not as clear cut. I had only my wife with me (not interested in hi fi, no bias and calls it as she hears it). First we played the ERC version. I was disappointed as I was hoping it would blow me away but in fact it sounded just like the 1969 release sounded when I first heard it (then, the process was the same as it is now with ERC so it shouldn't sound different). When Stephen Stills sings "it's my heart" it comes from right of centre, and as he holds and extends "heart" it sounds as if he is turning his head to the right away from the microphone so that the word moves back to the right and then fades into the background. When the person on the left of the microphone is singing in Spanish, his head is three-dimensional, the illusion picked up by micro movements perhaps?
The MoFi Ultradisc One Step was then put on. The volume had to be dropped a couple of clicks as before to make listening levels the same. What I noticed is the voices were clearer, a bit more forward and easier to discern. The instruments were clearer as well. That part with Stephen Stills singing "my Heart..." doesn't sound as if he turns his head from the microphone to the right and his voice picked up in the distance reflecting from the back of the studio, instead it sounds like his head is stationary and the volume of "heart" just turned down. The Spanish singing too is not three-dimensional, but sounds as if picked up from a speaker broadcasting it left of microphone, not a person. My wife, she said the MoFi recording is clearer, they sound different but would not say one was better than the other.
MoFi tells me (email response) that Marvin Gaye was 1/4"/ 15 IPS Analogue Master to DSD-64 (bit stream at 64 times CD sampling rate) to analogue console to lathe (where is the DAC?) one-step. The MoFi Ultradisc of CSN however, is 1/4" / 15 IPS Analogue Master to DSD-256 (much faster than the Marvin Gaye), to analogue console to lathe (again, where is the DAC). On the surface, one could argue that whereas DSD-64 wasn't sampled fast enough to challenge analogue, DSD -256 is. There is also an often reported story that the original recording and mastering of CSN was not great, as evidenced by a bland presentation on ERC and therefore aspects of it could be improved in the digital realm. Whatever the reasons, I must admit that the DSD-256 modified CSN did sound better than the ERC pure analogue recording generally, but in no way did the MoFi DSD-64 modified Marvin Gaye sound as pleasant as the pure analogue Supersense acetate.