Recently arrived - a Miyajima ETR-Mono step-up transformer. Not the simplest device to use (I'll come to that in a minute). But the biggest question for me was whether I needed it at all, having been so happy with my EAR 912 phono preamp, which replaced some Hashimoto HM-7s (the best SUTs I had owned out of many in a list that included an AN-S6c and a fully implemented TX-103), an Aurorasound Vida (widely regarded as one of the best phono stages out there), and assorted quality preamps including a Modwright 36.5 and a truly cracking Radford Revival prototype.

The EAR 912 is a true Swiss Army knife when it comes to the whole business of vinyl, and moving coil cartridges in particular. Its internal SUT is broadly similar to EAR's stand-along SUT the MC-4, but not quite the same in terms of ratios (and also supposedly made to a higher standard). It provides the following in terms of settings:

x 30 step-up, giving a cartridge loading of 52 ohms into a 47k ohm phono stage (labelled 3 ohms, for low impedance cartridges)
x 24 step-up, cartridge loading 82 ohms @47k (labelled 6 ohms)
x 18 step-up, cartridge loading 145 ohms @47k (labelled 12 ohms)
x 10 step-up, cartridge loading 470 ohms @47k (labelled 40 ohms)

I'm informed by a fellow AoS'er who asked Tim de P at a show 'why these settings?', and he answered that these are the most commonly used values in Japan - 3 ohm for SPU, 6 ohm for Koetsu, 12 ohm for lots of ATs and many other mainstream cartridges, 40 ohm for Denon 103 and other oddball cartridges. Which makes total sense.

The other features on the all-tube (5 x PCC88) EAR 912 complement the SUT options nicely: two tonearm inputs, a toggle switch between MC + MM setting which allows the step-up stage to be bypassed, and perhaps most important of all, an absolutely top moving magnet phono stage that provides RIAA correction on LR (inductance and resistance) principles, as opposed to the more normal CR (capacitance/resistance) type. I had previously thought this was LCR, similar to Aurorasound Vida and several Allnic models, but LR it is indeed when it was introduced back in the early 00s it was the first ever to offer this - based around EAR custom wound inductors, such windings of course being a Tim de P speciality.

The phono section is high gain, especially when the appropriate ratio for a given cartridge is quite a high one, so yet another custom transformer is present in which nicely matches gain between phono and linestage - options are 0db (for no attenuation), -6db and -12db for different levels of gain. This is what the VU meters are for - to ensure things stay nicely in the ideal zone for gain.

The result is a seriously flexible piece of kit, which manages to be more than the sum of its very high-quality parts and does (I think) more than enough to justify its £9,370 list price (not that I paid that for it, thankfully having picked it up second-hand). I've tried it with quite a number of stereo cartridges (well over a dozen) and never found one I couldn't find a setting for that didn't sound ideal. There are potentially a few outliers, though the amount of gain in the system convinces me that it would very probably handle most cartridges at the low impedance/low output end of the scale - including for example the Audio Note Io (1 ohm at the cartridge coils, 0.05mV output) - given how well it recently handled several borrowed Fidelity Research cartridges with 1-2 ohm coils and outputs of 0.1mv, with no lack of gain or impact on the sound from an impedance mismatch. Indeed I believe the only real gap could be said to be at the other end of the output scale, vintage cartridges, mainly mono, with high-ish outputs and oddball coil impedances in the region of 1000-3000, like the 1.5mV Ortofon CD25.

But with modern mono cartridges such as the Miyjima Zero, Premium, Spirit, Kotetu and the rest that I've been playing with for about 8 years now, the EAR SUT section works beautifully and it never occurred to me that what I was getting could be improved in any particular way. The EAR 912 has a mono button, not that you really need it with a mono cartridge, and I've been very happy.

However, audophilia nervosa is never that far away, and a conversation with Hugo of Ammonite Audio, who was enthusing about the ETR-Mono, made me want to investigate - after all, this was a SUT specifically intended for use with Miyajima mono cartridges, of which I own three (though it's flexibility goes way beyond the demands of the Miyajima range).

When it arrived, it took me a little while to fully appreciate how it worked (I'm not going to attempt to go into the detail in this post as Hugo has explained it really well here https://ammonite-audio.co.uk/thought...-etr-mono-sut/ ) - but essentially, there are a range of input coils which map broadly to the impedance of the cartridge in use, and output coils that map to the gain required. There’s a ton of maths behind the selection, but what I’ve found it that the maths line up with the listening experience. There is a third knob which trims the loading (effectively enabling the overall loading into the phono stage to be altered), I have found this useful too, which (interestingly) isn’t quite what Hugo found.

Anyway I’ve already uncovered the perfect settings for the Miyajima Zero 0.7 (which I used for later mono and for most reissues), Miyajima Premium 1.0 (earlier microgroove mono) and Miyajima Kotetu 78 (for 78s) - all slightly different as their coils and output levels vary. With the Zero in particular I’ve found it has taken performance to an new level - keeping the great horizontal wall of sound that it’s famous for (mono in widevision I call it), but with a shade more detail, more expression, more musicality. With the Premium, which has a part-bamboo tip done by Ana Mighty Sound, it modernises the sound every so slightly and makes it sound more like what I get from Zero .. it seems to clean up the sound in a way that the stereo SUT doesn’t, which is just ideal really - it's always been my view that a lot of old recordings sound old and vintagey simply because we've lost the ability to reproduce them correctly. I have a CD purchased from Pristine Classics that exemplifies this - a masterpiece of work by Andrew Rose, who took some 1929 recordings of Cortot and Thibaud (famous pre-war violin and piano duo) playing Beethoven, and restored it to sound superb - you would simply never fathom this as an 89 year old recording. Likewise there's no reason for 1950s stuff to sound poor - it's just a question of finding ways to get closer to the original recording.

Having said that, compared to the EAR, the Miyajima's changes are subtle, not night and day. There was absolutely nothing ‘wrong’ with the EAR’s mono capability - this just kicks it up a notch. And the precise settings matter a lot - it’s easily possible to make things sound worse. What I’ve found too is that I’m not using it as a tone control - quite simply there are ‘correct’ settings for the cartridges and these don’t really vary from recording to recording. Of course I have my Esoteric Re-equalizer to handle recordings that were created prior to universal adoption of the RIAA equalisation standard. In combination, I really feel I’m getting to the heart of mono reproduction in a way that I wouldn’t have expected even a few years back.

A bonus of course is that this new, all mono Swiss Army knife is not restricted to Miyajimas ... what I want to do now is check out other mono options, perhaps with more advanced stylus profiles than the conical Miyajimas … the Ikeda 9 Mono is very much in my sights (just need to find one s/h or ex-dem as the new price is a wee bit off-putting!). But I'm sure it could equally be used for Lyra, Koetsu and others who have created quality mono cartridges.

The fun continues!

Current mono cartridges: Miyajima Zero 0.7mil, Miyajima Premium/Ana bamboo cantilever 1.0 mil, Miyajima Kotetu/Oto-no Edison Replika 78 4.0 mil, Sonovox MC-4 LP10 1.0mil, Shure M44/7 mono strapped with assorted Expert Stylus tips for 78 2.5-3.5mi
Current stereo cartridges: Miyajima Madake, Miyajima Takumi, Ikeda 9C III, SAEC C-3, Ortofon SPU Royal N,