First: A Re-Cap and Summary of Our Ongoing Tests of 1:1 Signal Transformers
- 1) A long time ago my know-all friend, taskmaster and torturer icefox informed me of the UMI 1:1 Transformer (then between 1st and 2nd gen). I had always been around transformers, including Input and Interstage Transformers (which can be 1:1) and was interested. Note that icefox and his 富贵 WE friends all use the rare and formidable vintage 天花板 WE91A.
- 2) I first tested the waters with this Reisong Transformer, which is significantly cheaper than the UMI. My impressions were favorable (as quoted below).
- 3) I bought one of the 1st gen UMI for our writer ELO, and tested it myself. It was hard for me to choose between the UMI and Reisong (as quoted below).
- 4) In my 2022 Year in Review I expounded on this topic and the gear. Remember China was still in lockdown and Border Control was not what it's now. I wrote: "...yet to be written up, kudos to icefox (his crowd use the rare and expensive WE91A), I started playing with 1:1 transformers (the 1:2 and even 1:3 versions are for cellphone and BT users who need the extra gain, beware). Used between source and preamp, the difference is so sharply etched it’s mind boggling; used between preamp and amp, the improvement is a little less but still obvious. I’m using 2, in both positions now. I have the fortune of experiencing a new kid on the block, UMI (bought it for ELO), which has truly superior bandwidth but, at least between the DAC and preamp, my heart tilts just a little towards the older and more old-world sound of Reisong (available on Aliexpress). This is not at all the first time I have transformer coupling between stages. The excellent EAR 912 that I had has transformer coupling at every stage (input, output and interstage)..."
- 5) ELO finally got to write about it ( LOL near the end of 2023! here). I was very happy that it basically transformed his journey! I editorialized a bit: "...Where should this thing be used? Well, basically it's an impedance matching device and those who use long interconnects (like I) shall reap bigger benefits. I think the greatest effect shall be between source and preamp. But, effect can also be heard between preamp and amplifier. Think about this, many HIGH-end products employ Input and/or Output Transformers (a great example would be the EAR 912)...Well, for sonic findings I must say I completely concur with ELO. I also found it astonishingly detailed and the stabilizing effect highly beneficial to the system. I also found it was a tad cool in my system. Mind you, I also had the much cheaper Reisong 1:1 counterpart, which I have mentioned now and then but never really formally reviewed. That's for a reason. In my system, I ended up using TWO, one between DAC and Preamp and another between Preamp and Amp. The Reisong saved me a lot of money and has a much smaller footprint. BUT, it's a fact that the UMI has superior bandwidth. Whereas, the Reisong is a little warmer and more musical, though some will find it a bit rolled off at both ends. I had only heard the UMI brand new (and not run in) and I still pine for it after its departure. I suspect I shall get a unit at some point (especially after ELO's opinion). It's not often that one hears a transformer that is so transparent - consider it a job very well accomplished. Would be curious to hear the Mk II also..."
- 6) I finally got an UMI myself (2nd gen) for testing. It went between my DAC and Preamp for the longest time. Some of my friends in NYC also got theirs. Their opinions are fascinating too (yet to be published)!
- 7) I wrote the formal first of my UMI article in Chinese (here). Basically it's a review of the function of a 1:1 Signal Transformer.
- 8) Further Testing of my UMI 1:1 in my HK home (here)! With hyper-critical icefox and Taimonsing! Great stuff! I left the UMI in the hands of Taimonsing to circulate among his friends.
Reisong redux in Shenzhen I After I left my UMI to my HK friends I hooked back in SZ my Reisong between the DAC and Preamp. What did I perceive? Perhaps, compared to UMI, the sound field has shrunken just a little or perhaps the dynamics appeared slightly more restrained, but things were still in good order. Smaller formations, solo instruments and quartets etc sounded luxuriant, likely even more so? This is a small setup in SZ and I was OK with the music, not being in the critical mode most of the time.
- The Benefits of Transformer I think it's very useful (my article in Chinese on general principals here; ther are more to come). Think about this, after my initial good impression I ended up with two Reisong's (after I heard the first one I bought the second), between the DAC and Preamp and between the Preamp and Amp. When I got the UMI I tested it between the DAC and Preamp, but I still had the Reisong between the Preamp and Amp. In the last paragraph above, you can infer that I am a confirmed user of two (even if I'm temporarily without), even if the one between the preamp and amp has less effect than after the front end (but less does not equate none). If one's amp is a true integrated, with an active gain line stage (much rarer than amps with a passive volume knob masquerading as integrated; Taimonsing's amps featured in the last article all have an active preamp gain stage), one uses only one. But, keep in mind, many cost-no-object designers use interstage transformers within the amp, which is like inserting a transformer between preamp and amp. Wherever it's in the signal path, the trannie of course has to be of good quality; otherwise, negatives from bandwidth limitation to other anomalies will rear their heads!
- The Character of Reisong To me, the Reisong is temperate and subtle. Compared to the UMI, it is a less upfront in its personality, meaning it's not prone to show off. In this respect, Taimonsing's view that it's more neutral is tenable. What is fascinating is that I view the Reisong as a little more luxuriant sounding (and hence one can interpret this to mean it's less neutral). This may boil down to the difference between systems. Here, I'd like to point out that, initially, even if I possibly preferred the Reisong to the UMI Mk I, I thought the Reisong might be a little rolled off at the top. Here's a little input from my NYC friend Andy. He thought that, compared to the WE 111C, the Reisong is rolled off too (but his downstairs horn systems are rolled off to begin with). However, let it be known that in my systems (both SZ and HK) now, with the Reisong's having had hundreds of hours of play, I don't feel at all there's any significant high frequency roll-off! I suspect that the Reisong needs more run-in to sound its best. I'm still perplexed by the Micromega Solo experience mentioned above, and wonder if the loss of spatial clues is tied to some kind of frequency anomaly, even if I don't feel there's any indication of that when listening (certainly not Taimonsing either).
- The Character of UMI To me, the UMI is more dramatic. It seems more extended at the frequency extremes, and the way it expands the sound field and ups the flow and excitement factor is like grabbing one by the balls. Compared with the Reisong it almost certainly has a little less midrange richness (that is not a trade everyone is willing to make). Taimonsing said he has reservation about the smidgen of silver touch (the UMI has a little silver wiring inside). BUT, to me, and our writer ELO (who has the very similar Mk I; his views here) we love the drama it provides. Here's another interesting feedback: my NYC friend Andy thinks of the UMI as somewhat beautifying, even in his upstairs full frequency system; whereas I don't feel so (likely ELO and Taimonsing too). This leads me to ponder what exactly is beautifying. I think, perhaps expanding the sound envelope itself, which the UMI certainly does (more than the Reisong) is an act of beautifying...Fascinating! Also, the UMI didn't seem to need more run-in.
- UMI vs Reisong The reason why I have left these in HK for friends to test is because personal responses are inconsistent (as in audio in general). Taimonsing was initially quite impressed by the UMI but later preferred the Reisong. Andy in NYC (and freiends) seem to be impressed more by the UMI. And I? Well, I like both! I think the result one gets is system and gear dependent. That said, I think both will bring improvement to most systems. Keep in mind that the Reisong costs just a fraction of the UMI (not that the latter is unaffordable). I also heard through the grapevine that they also compare favorably with the much more expensive local 潘氏.