Reprinted with permission from UHF Magazine No. 87 (450) 651-5720 www.uhfmag.com

Allnic Step-up FeedbackListening Room

Moving coil cartridges are often referred to, incorrectly, as having low output. In fact what they have is low impedance. And perhaps that calls for a little explanation.

A cartridge’s output power can be defined as its voltage multiplied by its current (assuming voltage and current are in phase, but let’s not complicate things). A typical moving magnet cartridge will have an output at relatively high voltage (perhaps 2 to 3 mV) at low current. A low impedance (MC) cartridge will have perhaps a tenth of that output voltage, but it will be able to supply higher current. The output is therefore not really low, merely different.

That causes a problem, however. A phono preamplifier expects to “see” voltage, and so low voltage might as well be low output. The usual practice is to add extra amplification to increase the voltage to what you would get from a high impedance cartridge.

But amplification stages add noise and distortion, and there is another solution that used to be common. A step-up transformer can trade off current against voltage, and allow a low impedance cartridge to drive a phono preamp with no extra amplification.

So why doesn’t everyone use transformers? It’s because making one good enough for a tiny signal requires extraordinary precision work, and it’s not the sort of craftsmanship you can easily automate. Because a step-up transformer

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handles such a small signal, it requires extraordinary shielding against the electromagnetic interference generated by our increasingly connected world. The result is that, over the past decade or more, we have heard step-up transformers whose sound can be charitably described as disastrous.

We ourselves have long owned a Bryston TF-1 transformer, which was once an everyday element of our reference system, and which two decades ago was surprisingly affordable, perhaps around $450 (we’re quoting this from memory). Though Bryston still uses that transformer in some of its preamplifiers, it no longer offers it as a standalone product. Certainly it would cost several times more today, and it was a bargain even when we acquired it. Hammertone Audio shipped us an earlier model of the Allnic, and then asked us to send it back and try this newer one instead.

The AUT-2000 is in a massively- shielded box, with holes that look as if they are made for heat dissipation, though of course the tiny signal produces no significant heat. The twin switches, which can be set with a coin, can vary the gain from the multitap transformer to provide the best signal that won’t overload the MM (conventional) input of the phono preamp. We ran them all the way up and noted that they did not overload our phono preamp even on the loudest passages we could find (obviously, your mileage may vary).

We did note a glitch: we thought we had lost the right channel, and began

looking for improperly-inserted interconnect cables, only to find that one of the Allnic’s switches was not set just so. The switch detents are not as positive as they could be.

We did our listening in our Alpha room, connecting our Bryston to our Audiomeca J-1 turntable and Goldring Excel moving-coil cartridge. We listened to four selected LP’s, and then repeated the session using the Allnic transformer. We used one of our Atlas Navigator All-Cu interconnect cables between transformer and preamp.

The first thing we noted is how very quiet the Allnic was. Of course you would expect a transformer to be quieter than a low-impedance amplification stage, but that will be true only if the shielding is adequate and if internal grounding has been done properly. Phono preamplifiers are often noisy in our Alpha room, whose ungrounded lead-filled side wall pulls in plenty of less-than-delightful radio frequency interference. Not in this case.

The first selection was our all-purpose test, William Walton’s symphonic suite Façade, which we played from Reference Recordings’ RR-16 LP, though it is also available on CD. The distinctive timbre of each instrument (each getting its own solo) was easy to appreciate, because there were details aplenty. We noted the excellence of the sound of the clarinet, the trumpet and the bassoon. However the sound coming through the Allnic is more organic than this suggests, with a proper blend to make a whole. The orchestral sound was lively and joyous. The Allnic was at least going to keep up with our own transformer, and Steve was already prepared to give it the cup.

Could we overload the Allnic, as we have succeeded in doing with some other transformers? Of course we could then cut back the gain. A direct-cut disc might tell the tale. We moved on to a piano recording from Japan Victor, of American pianist Edward Auer delivering a high-energy rendition of Chopin’s Scherzo No. 2.

We certainly didn’t succeed in overloading it, but we didn’t quite agree on what we heard. Albert and Steve gave the edge to the Bryston, with Steve finding the Allnic a little brighter, with less sonic contrast between the energetic chords and the softer notes. Gerard disagreed, finding that the Allnic made Auer’s Steinway piano seem larger.

We wanted to include a couple of female voices, knowing as we do that the higher tessitura of female voices is fraught with peril for audio gear. Yes, for analog as well as digital.

The first of the pieces was from Dolly Parton, whose high-perched clear soprano is a challenge to any playback system. We selected I Really Got the Feeling from Heartbreaker (RCA AFL12797). No, you won’t find it at Amazon, though it was a best seller, and plenty of used record stores stock it.

This time the Allnic scored a major victory, with Dolly’s voice sweet and resonant, with superb articulation, presence and intensity. The orchestral accompaniment was delightfully rich. The highs — and they’re nothing if not plentiful — were clean, without any trace of electronic contamination.

The second of those recordings was from Barbra Streisand. Though Judy Collins is famous for her recording of Send in the Clowns (from the musical A Little Night Music), we consider that Stre isand did the definitive version on her Broadway Album (Columbia OC40092). That LP is also discontinued, and the CD re-release gives dreck a bad name. But we digress.

On this emotionally-charged song, with its decidedly bittersweet tone, the Allnic transformer really showed what it could do. The great sonic clarity served the song well, spotlighting Streisand’s acting talent as well as her vocal mastery. The lyrics were even clearer than with our own transformer. So were the voice variations Streisand used to such good effect, though without ever exaggerating them.

This is, then, a very fine step-up Brand/model: Allnic AUT-2000 Price: US$1600 Size (WDH): 16 x 11.5 x 5.8 cm Most liked: Quiet, detailed, musical performance Least liked: Weak detents on the rotary switches Verdict: Building one is tough; build- ing one this good is tougher Summing it up… device, the first usable one we have seen in a while. Who is the logical purchaser for it?

With the surprising resurgence of analog over the past half decade, low-impedance phono cartridges have become more popular than ever. One result is that electronic designers have become much better at designing outstanding phono preamplifiers with moving coil inputs. Some of them work so well that you might wonder who still needs a transformer, even one as good as this.

Yet the natural advantage of a good transformer over an active amplification stage remains. Indeed, some very good phono preamps can’t actually accommodate a low-impedance pickup. Tube preamplifiers are but one example, and if a tube phono preamp has an MC input at all, it will have been added via a small solid-state amplification stage whose presence runs counter to the preamp’s very raison d’être. Enter this transformer.

We’re happy to see that step-up transformers of this quality can still be made. We wish there were more of them.

CROSSTALK As I understand it, the Bryston has held its own without any real competition for quite a while now. This is true no longer. The Allnic presented each of Streisand’s vocal inventions to the last detail. Dolly’s vocal styling seemed to be surrounded with a halo of delicious musical realism. I noticed too that the recording studio’s height and width were easy to hear. All in all, I prefer the Allnic. Step up to it. It is capable of transforming your vinyl system. —Steve Bourke

Why would you have a wonderful cartridge unless you match it (if you need to) with an equally great transformer? Besides its original purpose, such a device truly acts as a filter that stands in the way of the music you’ve painstakingly attempted to recreate through your system. Ideally, it should be as transparent as possible.

This one disappears the way your windshield disappears after a good cleanup, and the world you’re driving through appears for the first time with utmost clarity. No murkiness means better contrast, in sight as in sound, more detail where you thought you knew all there was to hear, all there was to feel.

You might be touched by lyrics you knew by heart but never heard uttered with such delicacy. I know I was. Not at first, mind you, but later on, as I stopped analyzing the sound and allowed the music to flow. —Albert Simon

I find it dispiriting that there aren’t more quality step-up transformers available. In fact there aren’t many of them at all, and it had been years since I had heard one that was even passable. Why is this?

I suspect it’s the same reason that the very best phono cartridges have soared in price over the past few years. You can’t make a top cartridge by machine, and anyone who can do delicate hand work while squinting through a microscope is going to demand serious money. You can’t increase production on such products just by adding a night shift.

And it’s apparently much the same with step-up transformers, which must be accurately wound in order to handle vanishingly tiny signals. Remember that the 2.5 microvolt output of our cartridge is the maximum output. Imagine what the voltage must be 60 decibels below maximum. Hey, analog is hard!

But Allnic has gotten the job done. This transformer is quieter and clearer than an electronic circuit. When you consider the magnitude of the challenge, and how seldom it is met, I consider the price to be surprisingly low. —Gerard Rejskind

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