I’m new to SUTs, better known as Step-Up Transformers, small passive boxes that enable your moving coil (MC) cartridge and phono stage to work to their fullest potential. Many MC cartridges have very low output, much lower than a moving magnet cartridge; as such, they need more gain from a phono stage to be played at normal listening levels. While many fine phono stages have a section specific for moving coils, the technology used, FETs or tubes, often adds noise to the system. A well-designed and wound Step-Up Transformer can drop the noise floor lower resulting in better sound.

Henley Audio offers a detailed explanation of the science: Where phono stages, as part of their signal amplification, will have a constant resistive input impedance, Step-Up Transformers have a frequency-dependent input impedance. Step-Up Transformers are also passive (i.e. not mains-powered) devices, reducing the chance of external electrical forces impacting the cartridge's low output signal. The result of a Step-Up Transformer's design is that they can amplify the MC output level and produce less harmonic distortion as the frequency rises - which is the opposite effect of a phono stage. This results in a cleaner electrical signal and more dynamic sound performance from the cartridge in a wider, deeper soundstage.

I’d heard of SUTs over the years and knew some experienced audiophiles who swear by them but I thought why add another box, another cable? Who needs one if you have a fine phono stage? My phono stage is the outstanding Phasemation EA-350 Phono Amplifier (USD 6400) with a very fine MC section. I’ve never used the MM input, but the EA-350 is a multi-function solid-state unit, perfect for a busy audio/music reviewer.

During a regular phone call check-in with my friend John Stratton (of Pure Fidelity Turntables), he suggested I try a SUT he’d been auditioning; he was hearing exceptional results. “Do you want to try it”. “Sure, why not”, I replied. A few days later it arrived on the Island.

The small unit is the beautifully made, striking EAR MC4 Cartridge Step-Up Transformer (USD 2500, and at par CAD 2500, which, at the exchange, makes for a wonderful deal).

As noted on the thick chrome front plate, the MC4 was designed by Tim de Paravicini. Tim died in 2020 from cancer. I had the pleasure of conversing with him on Facebook before he died—tubes and remastering vinyl records, two of his favourite subjects. Tim was a passionate idealist, a brilliant engineer who through his company EAR Yoshino (1977), designed and manufactured many fine tube-based products. Tim was an alchemist with transformers, too. And with SUTs, the magic comes from how the transformers are wound; the “recipe” if you will. And no one was better at building and winding transformers than de Paravicini.

The MC4 was one of three SUTs I have in-house for audition and comparison. In addition to Stratton, I’d like to thank David Jensen of Red Leaf Audio for providing the Ikeda IST-201 MC Step-Up Transformer (USD 5400) (review up June 1) and Don Corby of Corby’s Audio for providing the Allnic Audio AUT-8000 Step-up (USD 4800). I had a magic garden of SUTs with which to play.

My Use

SUTs are among the most simple high-end devices to hook up. However, it is important to choose a transformer that will work with the impedance of your MC cart. I would be using the three SUTs with my Phasemation PP-2000 MC Phono Pickup Cartridge (4 ohms). 4 is low impedance—the EAR can accommodate cartridges of varying impedances.

Connection is straightforward. The turntable phono cable is plugged into the input and the output by interconnect to the MM input on your phono stage (Don Corby suggested using an additional phono cable for better impedance matching. I used an Ansuz C2 interconnect and an Ansuz phono cable and heard no differences. YMMV). Unlike some other SUTs, the EAR can handle a wide variety of MCs—choose the impedance input that best matches your cartridge. For my 4 ohm Phasemation, I used the 3Ω (30x output). Others are 6Ω, 12Ω, or 40Ω. These produce an output of 24x, 18x or 10x input voltage, respectively. Be sure to use the ground, although I had no hum issues with the MC4.

Specifications

- Frequency Response 3Hz- 100KHz +0.2dB-1.0dB

- Phase Linearity Less than ±5 degrees (20-20KHz)

- Rise Time 2µSecs (any level)

- Channel Balance Less than 0.1dB

- Channel Separation Greater than 70dB (20-20KHz)

- Hum Rejection Greater than 60dB (External Magnetic Fields)

- Equivalent Noise Contribution Less than 1dB

- Voltage Gain X30, x24, x18, x10

- Input Impedances (nominal) 3 ohm, 6 ohm, 12 ohm, & 40 ohm

Sound

Break-in is very important on all three SUTs under consideration. I could hear the improvements from the EAR over my Phasemation MC section immediately out of the box. But break-in, rather than annoying, is a pleasure as moment by moment the EAR continues to reveal the most wonderful details from your valued record collection.

As an opening gambit, I tried a new addition to my record collection, a near-mint Soria RCA Indianapolis early stamper of Charles Munch’s legendary Berlioz Roméo et Juliette (1839). The vinyl, clean as a whistle, sounds as fresh as the day it was pressed in 1961. Specifically, I wanted to hear the “Queen Mab” Scherzo, a remarkable feat of orchestration, so fleet and delicate, that only the very best in analogue may apply if you want the full effect. Reverting to the naked Phasemation, the sound of the RCA LP was wonderful, but this SUT was adding some magic of its own and right out of the box.

The EAR’s initial performance had me grinning. What a lovely surprise—it’s tough to surprise this audiophile after countless reviews and 30 years in the business. We know for serious audiophiles, even worse, vinylphiles, we’ll walk a mile for a 1% increment in effectuation. But the EAR was adding more than that; better soundstage, faster response but most of all timbral beauty. The damn thing sprinkles fairy dust over the performance stage. My God, the Boston Symphony muted violins sounded so sweet via the MC4, no matter the tempo. And the beauty of their centred tone was magical. The performance of this masterpiece under the Phasemation MC was very beautiful, but the MC4 took it to the divine. Is that 1%? I don’t know, but at first blush, the SUT experiment would now be difficult to remove. Once heard, difficult to unhear!

As I was listening, I was reading everything I could gather about SUTs and their technology. I decided to keep it simple and think big picture—transformer winding and the sound emanating from that. But like everything audiophile electrical, you can be swamped the weeds—impedance, input, output, primary winding, secondary winding, turn ratios, phase deviation, transformer noise and hum rejection. Dizzying! You can ignore all that and just ensure you have a good match for your cart’s impedance, keep the (quality) cables as short as you can, place the SUT away from power supplies, and connect the right way. The diagram below is probably all you’ll need to know if you’re slightly inquisitive.

The exquisite tactile treble from Oscar Peterson’s right hand never ceases to amaze me on We Get Requests. Whether "Quiet Nights Of Quiet Stars (Corcovado)" or "You Look Good to Me", Peterson’s touch is gossamer, but now with even more of that “fairy dust”. Remarkable sound from my Japanese pressing and Peterson’s technique. Less dust on Bill Evan’s more direct technique on Bill Evans/Behind The Dikes: The First Official And Complete Release Of The 1969 Netherlands Recordings on Elemental Music Records vinyl. These recordings, now set on three marvellous LPs, are remastered from the original Radio Hilversum analog tapes by Bernie Grundman. And my recollection of them at first listen was vivid—great sound with Bill’s invention front and centre. The MC4 gave me more Bill, more of his amazing trio, and cast a lovely glow around the orchestral tracks, which I thought less successful than the trio recordings when first auditioning. The orchestra sounds fuller and richer with the MC4 in place.

It was the same for voices. Compared to the Phasemation’s MC, nothing earth-shattering, simply an inner glow and more of that transformer alchemy. In all repertoire, the MC4 was more coherent and tightly controlled (in the best musical way) than the Phasemation’s MC section. As such, I am completely convinced of the power of a quality SUT. And I have three from which to choose. My choice will be revealed in a later video on my YouTube Channel (yes, there is one that has been chosen for my reference—it’s transformative). Yet, in the here and now, I can recommend this superb SUT for its wonderful sound and relatively inexpensive price. At USD 2500, the EAR is almost half the piece of the Ikeda and Allnic I’m auditioning. And it plays well with all sorts of moving coils. A remarkable deal to significantly up your analogue MC game. Very highly recommended.

Further information: EAR Yoshino