REFERENCE COMPONENTS-STEP-UP DEVICES

There is not much choice in this category because very few "all-out" step-up devices have been made by the audio industry. They were discouraged 20 years ago by the influential (at the time) magazine The Absolute Sound. In their combined idealism and technical ignorance, pointed out by both The Audio Critic and International Audio Review, they influenced preamplifier manufacturers to build high-gain preamplifiers instead.

The results of this campaign were units that were far inferior to what was achievable with superior step-ups and low-gain phono stages. Only that combination can retain the true dynamics, body and low-level detail of the original signal.

Ironically, when a manufacturer in the late 1990’s finally did create a superior high-gain preamplifier, with an internal step-up, virtually no one took any notice. In fact, The Absolute Sound never even reviewed it! I placed this unit (Audion Premier Quattro) within Class A of the Preamplifier section.

Note- Moving-coil cartridges generally have more overall energy than moving-magnet cartridges. This is mainly because their (stationary) magnets are more powerful than those that are "moving". The problem to overcome is that their energy is mainly in current, while preamplifiers sense and amplify voltage.

This mismatch can be overcome by either amplifying their existing tiny voltage or transforming their excess (and otherwise useless) current into more voltage before it reaches the phono-stage of the preamplifier. The "phono-stage" then further amplifies the signal and also equalizes it at the same time, using the RIAA equalization curve.

Moving Coil Transformers- These are passive devices (with no power supply) that "transform" the excess current from the moving coil cartridge into voltage, which can then be amplified (and equalized) by the phono stage of the preamplifier.

Moving Coil "Head Amplifiers"- These are active devices, with power supplies, that amplify the tiny voltage from moving coil cartridges so that it approximates the normal voltage from a moving magnet cartridge. The phono stage must still further amplify and then equalize the signal.

Another name for this active type of device, that is also commonly used, is: Pre-preamplifier. Because it is "passive", the transformer has theoretical advantages over the "head amplifier", but execution is still critical for both devices.

I now feel confident to state that this is the finest moving-coil step-up I've ever heard. That even includes the Expressive Technology "Class A" transformer. My "associates" concur with this opinion. Our one major caveat is that it must be loaded correctly (details below).

The Bent Silver's outstanding performance has inspired me to write an in-depth perspective and history about Step-ups, which, despite their critical importance in a phono system, have probably been the single most ignored and neglected component category in both research and development. This audio apathy is the primary reason for the pitiful choice of models available to serious audiophiles.

We need "Step-ups" because the finest (low-output) moving-coil cartridges don't have enough voltage for a typical RIAA phono stage.
There are two methods to achieve this:
1. Simply amplify the signal beforehand with a "head-amp" (tube or transistor), or
2. Transform the excess current of the moving-coil cartridge into more voltage (with a transformer, obviously!).
(There are also "Internal" step-ups, already inside preamplifiers, that use one of the same two methods, but we are focusing on "External" (outboard) step-ups here.)

Which method is better? Well, that depends on personal priorities, execution (optimization) and when the comparison is/was made. I was fortunate to hear virtually every step-up in existence back in the 1980's and even up to the early 1990's. Since then, only a relatively few models have come out. I've heard most of them also, but there are atleast a couple of prominent exceptions (Audio Note and Jensen transformers). Here's a short history of my/our experiences:

Up until the early 1980's, moving-coil cartridges (and their required step-ups) were rare, but the successful Denon, Dynavector and Koetsu cartridges changed the entire phono playback landscape, quickly and profoundly. Suddenly, most serious audiophiles wanted moving-coils to replace their (now "old-fashioned") moving-magnet cartridges. (A Quick Reminder- CD players didn't even exist yet back then.)

Since these audiophiles had only "normal" (low-gain) phono stages, just as suddenly an avalance of (now required) step-ups came on the market. Most of them, as could be easily predicted, were mediocre, or even worse. Some were "OK", and a rare few were actually exceptional (Klyne, Cotter, RWR, Audio Research, Counterpoint, Conrad-Johnson, Classe etc.). I heard almost all of them, good and bad, either as a dealer, or as trade-ins by unhappy audiophiles, obviously because of their unsatisfying performance. (I wish I could identify "a diamond in the rough" among them for cheap, but there's none I can remember.)

Personally, I went from a Denon to a Cotter, then to a Klyne SK-2, then to the CJ, back to a Cotter and lastly to an Audio Research MCP-33 (my then favorite, along with the problematic Counterpoint, when working well). However, I finally gave up on ALL of these devices after they stopped evolving, and instead went to a Jadis JP-80 (which I still have!) and a high-output moving-coil; the excellent Dynavector XX-1, which did not require a step-up. The sound was superb, with no noises or other problems, and the system was simple. I was really happy at the time.

Then, from out of nowhere, and totally unexpected within the anti-step-up environment of the time, came a new component that "shook up the audio world" (or should have).

To appreciate the (then) unprecedented achievement of the Expressive Technology (ET), you must realize that, prior to its appearance, no step-up type, or model, ever had a clear advantage over the other(s). Every single one of them had easily noticeable problems. You just made your choice about which problem(s) least bothered you (a strategy that's still most appropriate today). In this instance, it was either excessive noise, loss of subtle detail and noticeable distortion etc. (headamps), or blunted transients, veiling, frequency roll-offs etc (transformers). That's why I eventually gave up on all the step-ups. But...

The ET was very different; it was as good or better than all the other step-ups in every area of performance. Its ultra-low "sound-floor", in particular, was truly outstanding. (So, maybe a transformer was the superior method after all?)

In short, the ET was the closest component to theoretically "perfect" that I, and my associates, were aware of at that time (1992). It was outrageously expensive ($ 2,500 to $ 3,500), but worth it, because it was a seemingly "final purchase". (I even received another huge and unplanned benefit; its 28 dB of gain allowed me to bypass my entire line-stage as well!)

I lived with the ET, with complete satisfaction, for 9 years. I/we eventually heard some minor problems with it, using a "bypass test" (see below), but they didn't bother me. Then I moved from Canada to the U.S. in late 2001. I sold the ET to a very grateful friend, since I wouldn't be able to use it for an indefinite period of time. Besides, I was also told that ET was coming out with a new and improved model, that even included a highly desirable phase-switch, for $ 5,000! However...

I was soon shocked to find out that the "new and improved model" didn't actually exist and, even worse, neither did the "older model" that I used to own! ET had apparently permanently left the audio business. Now what was I going to do? (Going "backwards" in audio is close to torture for an audiophile.)

I did the best I could by purchasing an EAR MC-3 Transformer, which ended up being an excellent performer, and it even had 3 different inputs to optimize it with almost any cartridge. Soon after, I was loaned a Bent Audio TX-103 transformer, in kit form, which originated from Stevens and Billington (SB) in England. It was even better than the EAR, though not as easy to optimize (or on the eye). The Bent even seemed to approach, but not equal, the performance (at least in my fading memory) of my much missed ET. So...

I decided to bring it to an associate who had owned the ET himself for 8 years, and was obviously very familiar with its performance. This was in October 2003. The (very thorough) comparison we conducted was actually with the Audion Quattro's (Internal) head-amp, which had been highly modified. According to my associate, this was the head-amp that had shockingly outperformed the ET in 2001, which is why my associate later sold it. So what happened...?

The Audion head-amp was better again, in almost every area, though the Bent was still "respectable", meaning it wasn't "blown away". I then asked my associate the big question:
"How did his ET compare to the Audion and the Bent?"
His answer was, as usual, immediate and to the point:
"The ET's performance was almost exactly half-way between them."
So, to makes things simple, if the Audion was a "9.5" (nothing's a "10"), and the Bent was an "8.5", the ET was a "9.0". My associate's assessment matched my own memory of the two transformers in my own system.

Before we finished, I made absolutely certain that I could not forget the approximate differences between these two models. I felt it could be critical in the future, and it would be...

Another associate called me around 9 months later (Summer/Fall 2004) with some interesting news. John Chapman, the owner of Bent Audio, had talked SB into making a (prototype) pure silver transformer. This was a fantasy of mine for many years, but I never thought I would actually hear one in real life. Even better news arrived later; I would get a "loaner" sometime in the Spring (2005), and I did. The eventual listening results were posted on this website.

To condense what I wrote and posted at the time; The Bent Silver was both Heaven and Hell. In short- it had superb performance, probably better than any step-up I had ever heard in my system, but it also had a disqualifying problem; its tonal balance was unacceptably lean and light. I didn't have the time to experiment with it, so I put it aside for what I thought would be a few months, but it turned out to be almost a year.
This brings us to the present...

I've known about "loading"* MC cartridges for decades. (IAR's 25 year-old write-up on the subject is excellent.) The Klyne head-amps, which I sold and owned personally, had both resistor and capacitor loading, but I've had very little experience loading transformers. Very few of them even had the accommodation for loading in the first place. I never loaded down the original Bent (Copper) transformer, and didn't originally load down the Silver either, mainly because I wanted to have a direct comparison between them. I kept the loading as my backup "Plan B".

The Bent Silver did come with a package of new resistors; enough to "ballpark", if not fully optimize, any cartridge. It also has two (easily accessible) binding posts to attach the resistor(s). Before I began, I first read the informative threads about loading on the Audiogon Analog Discussion Forum (highly recommended), and then I started with 20K. The results- Much more than I bargained for...

The "lean and light" tonal balance was now virtually gone and, as a bonus, the sound was even purer, more precise and had greater separation and inner texture. The sound-floor also seemed to drop. The overall volume also decreased, which concerned me, since I don't have much volume to give away. Then I went to 10K...

There was another noticeably qualitative improvement, though not to same degree. The sound was incredibly pure and natural, but it didn't matter, since the volume was now just too low for me to live with. After trying a number of values between these two, I ended up settling right in the middle; 15K. At this time, with this present system, it's the best balance of sound quality and volume that I can probably achieve.

There are people with considerably more experience with transformer loading than me, but I would still like to summarize what I have experienced first hand:

1. Loading makes a definite difference, and sometimes a huge difference, as with the Bent Silver,
2. The quality of the loading resistor(s) does make a noticeable difference (Holco and Vishay were better than the "stock" resistors),
3. Multiple resistors must be the same brand and type, or there will be a slight smearing and loss of focus,
4. Experimentation is required- I'm speculating now, but I believe every system is different, so the most precise resistor value from anyone else should be a start only, no matter how many components are the same,
5. When the resistor value is too high, the sound will normally be bright, forward, light and lean,
6. When the resistor value is too low, the sound will normally be dark, recessed and compressed,
7. I would start "high", and then go down around 25% at a time (40k, 30k, 22.5k, 15k etc.), until you feel something is definitely "wrong". Then you "back up" and start "fine tuning".

Finally, because I ran out of volume, I'm almost certain that my current load, 15K, is NOT the true optimum value for the cartridge and transformer. I suspect it is lower. In the future, if and when I use a more sensitive amplifier and/or speaker, I'll go through this entire process all over again, and report back the results.

The Bent Silver has the largest amount of positives, and the least amount of problems, of any step-up I've heard, if not any component in any category. Right now, in the "Honeymoon" stage, I can't definitively state that I hear any problem with it, short of a hint of a blunting that MUST be present due to inescapable reality that all transformers are made out of wire.

Still, I'm not certain that the (unavoidable) interconnect cables I'm using are not the main source of the "problem". I've already placed the transformers behind the turntable, instead of behind the preamplifier as intended, and suggested, by Bent. In doing so, I received a slight improvement (a little more direct, precise and dynamic sound). I intend to further rearrange my entire phono playback system later this year, which will minimize, if not eliminate(!), the cables' impact (the cable itself may be eliminated). For now, put another way...

The Bent Silver provides more musical information, in a natural manner, with less loss and other aberrations, than any other step-up device I, and my associates, have heard to date. It is as direct and immediate as can be imagined. It doesn't roll-off the frequency extremes. It is as tonally natural as any component, once it is loaded down. It is as pure and clean as a high-quality cable. It provides incredible amounts of detail, inner and outer, and at all frequencies, and without the sense that it is ever overemphasizing, or enchancing, any of it. It is dynamically uncompressed at all volume levels. It has greater separation of instruments, and less homogenization, than anything I've heard.

For just one relevant example; I've never heard massed violins sound so natural, individualized and detailed, all at the same time. The individual "shimmers" can be heard on a surprising number of records. This is done without any sense of exaggeration. Also, it does not, in any manner, "romanticize" the music. It is simultaneously natural, revealing, accurate and unforgiving.

It's as close to "not being there" as any component I've ever experienced, and I'm pretty certain it can be even further optimized. To hear its actual deficiencies, in my case anyway, will require an even better step-up, or a lot of time, but I'm starting to actually think that even a theoretically "perfect" step-up wouldn't be that much better than a totally optimized Bent Silver. That may sound foolhardy, but how much room for real improvement* can there be left for a component category that has now evolved to such a high level of performance? Of course, I hope I'm really wrong about this. Audiophiles crave big improvements, where ever they can find them.

*(I feel the same way about the best signal cables. Once you've heard an actual direct-connection, meaning a connection without any cable, you soon realize that the finest cables, at least in short runs, degrade the signal by only a small degree, so the room for improvement must be, by definition, also small.

Let me summarize how the Bent Silver compares to the other top performing models that I, and my associates, have heard:

Bent Silver Vs. Bent Copper- We've made several direct comparisons. (With proper loading...) The Silver is FAR superior in most areas; Inner and outer detail, immediacy, transparency, separation of instruments and voices, sound-floor, purity, focus, high frequency extension etc. The two transformers are basically equal in tonal balance, bass extension, the size of the soundstage and (macro-not micro) dynamic contrasts. In retrospect, I'm reminded, in certain ways, of the comparison I recently made of the ZYX Airy 2 with the superior Airy 3. While the details may be different, the overall final impression I had is quite similar.
Conclusion- The Bent Copper is still "Excellent", while the Bent Silver is "Great".

Bent Silver Vs. Expressive Technology- This is much more difficult, since I no longer have the ET. Still, it's my opinion that the evidence strongly favors the Bent Silver over the ET. My thinking on this is mainly indirect and somewhat complicated, so please bear with me. First...

Two of my associates actually made this direct comparison, using my own (former) ET. The Bent Silver was easily superior, but I think there may have been a problem, because the Bent Copper was also better when it was compared to the ET at the same time. This, of course, is a direct contradiction of the Bent Copper/Audion comparison my other associate and I made earlier. It also contradicts an experienced reader's direct comparison of the two units. However, I've been told that other listeners also preferred the Bent Copper to the ET. No reconciliation of all this is possible that makes logical sense, someone must be wrong or there were serious mismatches at the time.

My present take- I believe my other associate's more revealing (Audion) system, and memory, plus my own memory of the ET, override the Bent Copper's "victory" of that day, as well as the others. We also made multiple "bypass tests" with both the ET and the Bent Copper, though not at the same time, and while these tests can never be conclusive, the ET was slightly closer to the cartridges' direct-in sound to the preamplifier (it had less "rounding"). (It was this acid test that finally confirmed to us that the ET was not "perfect".)

In the end, considering all of the evidence, the ET and Bent Copper transformers must be reasonably close, but I still feel as I did when I first heard the Bent Copper; the ET will have the advantage in most systems. This brings us to the experiences of my 5 associates, and myself, who have heard the Bent Copper directly compared to the Bent Silver. These results were profoundly different to most of ET/Bent Copper comparisons...

Let's go back to the Audion/Bent Copper comparison described above. At the time, I felt the Audion was a solid advance over the Bent Copper. The Silver's advance equals, or even goes beyond, that. It is totally "mesmerizing" to the listener; in the manner that only a serious improvement can ever be. Five other associates, who have also heard the Silver, feel the same way about this degree of improvement that I do. In a recent conversation with the Audion's owner, he reiterated that he still felt the gap between the Bent Copper and his Audion to be quite large; also a serious improvement.

But how could the ET, with around half of the Audion's similar degree of improvement, equal the Bent Silver's total improvement? I realize that this is indirect (A/B/C/D) logic, but it's all we have right now. There's another common audio comparative methodology which I feel is appropriate in this instance; the ET/Bent Copper differences, no matter which one was preferred, have been almost always described as a "matter of degree", while the Bent Silver/Bent Copper differences are more described as a "matter of kind".

Another associate, with excellent listening skills, and who is intimately familiar with all of the transformers, almost instantly told me the Bent Silver "was better than anything" he's heard, including the ET. He previously didn't care for any transformer, because of their "veil" and "rounding" (which he had heard in the "bypass tests" we conducted together). The Bent Silver was a revelation for him. He was so impressed, that he even admitted to me that he never thought the tweeters in my system were actually capable of what he was hearing, and he had personally modified those tweeters himself.

Bottom Line for Me- If I had to make a choice, right now, between the Bent Silver and the ET, with only my present experiences and knowledge, I would, without any hesitation, choose the Bent Silver. My associates' enthusiastic observations only confirm this choice. Still, I realize that only a direct comparison with the ET, in my own system, can provide the final confirmation of that choice.

Bent Silver Vs. Audion- This is really "academic", because the Audion head-amp is Internal, and can't be used by any other RIAA stage. Still, in my memory, the Audion's degree of improvement over the Bent Copper did not equal the Bent Silver's degree of improvement. However, my associate, who owned the Audion, recently reminded me that the sonic differences between the Bent Copper and the Audion were quite large, and if I had heard them from a reverse perspective, I would be just as "enthusiastic". He may have a valid point here. I know this conjecture is all as "unscientific" and "subjective" as can ever be imagined, but I want to communicate this anyway...

I was "knocked out" by the Bent Silver, but not by the Audion (at least at the time). In stark contrast, everyone who has heard the Bent Silver has been "stunned" by it, even before the loading process. That means as much, or more, than a strictly analytical evaluation of its performance.

Now I wouldn't be shocked if the Audion (and the ET!) still had some minor sonic advantage(s) over the Bent Silver, and there's even one other "caveat" worth mentioning; I didn't hear the Audion's improvements in my own system. That may be relevant, though I'm an audiophile who can still be "stunned" when hearing other people's systems (or components) if warranted. Still, if I could hear the full Audion improvement, in my own system, at this time and with a more revealing system, I couldn't rule out being just as overwhelmed as I am with the Bent Silver.

This is all a "theoretical" argument of course, since the Audion "head-amp" doesn't exist independently of the full preamplifier it's part of, but I don't want to leave any of my thinking "off the record". This is because the Bent Silver is a true "breakthrough" in my/our experience, and in rare* (for me) events like this, everything must come out, or it never will. (In the hope of resolving this true "audio mystery", one way or the other, I will make an effort to bring the Bent Silver transformers to my associate's house and have another "shoot-out", with an improved Audion. If so, you will read the results here, because I feel this knowledge is still important to know, even if it can't be put to immediate use.)

* "Breakthroughs" are quite common events now in most commercial audio publications; printed or on the Internet. That's not my personal experience. In this particular instance, it's been 13 years since the last true step-up breakthrough; the Expressive Technology SU-1 (1992-2005). This is also the reason for my uninhibited excitement, after years of nothing but disappointments.

To repeat myself; This is the finest step-up that I and my associates have ever heard. It is so far superior to most other step-ups, they may actually sound "defective" in comparison. There is not one of us who has heard it that feels differently, but its outstanding performance can only be realized with proper loading. I found that out the hard way, wasting almost a year in the process.

According to John Chapman, of Bent Audio, the Bent TX-103 Silver is $ 1,275 finished, which is $ 450 more than the TX-103 Copper. This places it within the price range of numerous phono-oriented audiophiles. Thankfully, it's not the typical "crazy price" you now see for top-of-the-line components. As for availability, sometimes Bent has the Silver in stock, but if not, you are looking at a delivery time frame of around 3 weeks to a month.

If the Bent Silver is coupled with a good, tube, phono stage, modified if possible, you will have near "state of the art" performance, for a fraction of the usual prices of current "all-out" units. The emergence of this model should be a cause of celebration for vinyl lovers around the world, even if they don't know it yet. Remember that the step-up may be as important as the phono stage, if not the cartridge itself, to the final sonics. When was the last time that any "best of breed" component was this reachable?

If you are looking only for the best transformer out there, and can afford the Bent Silver, and are prepared to take the time to load it properly, my Reference designation of the Bent Silver is unqualified (short of some bizarre mismatch). I would get the 26 dB gain version and skip the gain switch. The extra 6 dB of gain may come in handy if you later attempt to eliminate the line-stage, which I have already done in my own system. I would place the transformers behind the turntable, so the tiny signal is boosted immediately, before it enters the phono cable going to the preamplifier (or phono stage).

If you can't afford the Bent Silver, my other Step-up References are still valid. These other models, most of them are mentioned above, are also excellent components, but their relative performance to the best available has now been obviously diminished.

If you don't like transformers, because their sonic problems have seriously bothered you in the past, I would still borrow this model if possible, and listen again, with proper loading, and without prejudice. Even my anti-transformer friend is crazy about it.

If you are still open to either head-amps or transformers, and can wait for a while, there is still one more step-up that may be competitive with the Bent Silver. It's the ZYX MC CPP-1 Head-amp. I have their new 26 dB model, which has just enough gain for my system. The direct retail price is similar to the Bent Silver, so that won't be a factor. I recently took a "quick (2 LP) listen" to it with an associate. It was all warmed up, but not broken-in yet, which may be critical, considering the tiny signal "strength" it's amplifying.

The results surprised us; Even with poor grounding, and an extra 1 meter interconnect in the signal path, it was still really impressive; with lots of detail, excellent high-level dynamics and extended frequency extremes. And this impression was made after we had heard the Bent Silver properly loaded down. In short, this component has a lot of potential. I hope to get to it by the end of March.

Who knows, is it actually possible that these two models may turn out to be the finest ever made of their respective types? If so, this era, now known for its minimal Step-up choices, may also become, most improbably; "The Golden Age of Step-ups"!

The Expressive was the only Class A step-up any of us had ever experienced. No other step-up that I am aware of, except the Bent Audio Silver above, even comes close to it. It is virtually flawless in sound quality. This company is now out of the audio business, another audio tragedy.

This transformer performs at its best with low impedance moving coils. It doesn’t work well with all cables, because of the potential ground/hum problems. The input impedance of the preamplifier should be 47K. The ET will improve the performance of all preamplifiers, with the single exception of the Audion Quattro, and maybe some custom models that have recently become available. It was very expensive at $3,500 U.S.. Very difficult to find used. This may be that extremely rare "final purchase". (I would avoid using their own phono cables. While they are very good and well made, there are others that are even better.)

FURTHER- Expressive Technology also had an "all-out" preamplifier, with a phono stage. They worked on it for 7 years. It cost $ 15,000, and only a few were made. This is the preamplifier that Myles Astor, of the (now former) print magazine Ultimate Audio, actually refused to listen to with his own analog front end. See "Reviewing the Reviewers". I don't know anyone who has actually heard it.

This is, most likely, the finest head-amp I've ever heard. I state this because it is competitive with the finest transformers I've had, while all the many other (external) head-amps I've heard are simply not in that league.

Disclosure- The ZYX head-amp is a solid-state device! It is highly unusual for a successful cartridge manufacturer to also design and build an audio component that is so different in fundamental nature (non-mechanical in this instance), with such excellent performance. The relevant details...

The ZYX basically equals the Bent Silver TX-103 transformer in immediacy, neutrality, frequency extension and the size of the soundstage. The ZYX has excellent channel separation, and the macro dynamics are absolutely breathtaking. In direct comparison, the Bent Silver is superior in two areas; its ultra-low sound-floor and its freedom from electronic haze. These areas are considered "subtle" by many audiophiles, though not me, and can be especially noticeable on certain acoustical music.

Please don't misunderstand me, the ZYX's background noise (hiss) is very soft, basically non-existant, and lower than any head-amp I've ever heard. It just loses a bit of individuality, harmonic completion, sense of space and micro dynamic "tension" compared to the Bent Silver. It's not alone, so does every other step-up I've ever heard. For the sake of perspective; the ZYX's "weaknesses", only compared to the Bent Silver, are still actual strengths compared to almost every other step-up I've heard. That's how good it is. In fact, there were many times I was not even able to distinguish between the two of them, because their basic sonic character is so similar*.

(*I wrote previously that I believed that even a "perfect" step-up wouldn't be that much better than the Bent Silver. This is because I felt that the Bent Silver is already pretty close to "perfect" itself. The closer components come to practical perfection, the more similar they must sound, no matter how differently they are designed and built. This is because they will have fewer imperfections to distinguish themselves from each other. “All happy families resemble one another, but each unhappy family is unhappy in its own way.”-Leo Tolstoy, Anna Karenina)

While both the ZYX and the Bent Silver are rated at 26dB of gain, the Bent Silver loses some of its gain as soon as it is loaded-down, which is a requirement. The ZYX is already "loaded-down" as is, so it has more real gain in practice. For many systems, this may prove irrelevant, but in my own system, it is the difference between some records coming "alive", or not. There is another advantage to the ZYX; it is virtually "cable proof", since it is an active device.

While signal cables, both to and from the ZYX, are still obviously important, there's never going to be a true mismatch. Sadly, this is still possible with the Bent Silver, because it is passive by nature. I've already directly experienced this potential problem. This reality can be critical for cable freaks and/or experimenters.

In short, the ZYX's high level of performance can be experienced in every system, while the Bent Silver, though it has even greater potential, will only reach that potential with time, effort, patience and maybe some further expense.

The ZYX's power supply consists of high-quality (9 NiCd) batteries, which are re-charged in a few hours (overnight is easiest). It broke-in very quickly, only after around 10 hours or so of play. It doesn't sound good for the first few minutes of each session (it's veiled, dry and ill-defined), but it warms up fast, and after 20 minutes (1 LP side), it's already at its best. It can also be played while the batteries are being re-charged, but I'm not sure about the sonic compromises, if any, while doing so.

Despite the ZYX's relatively small size, and its lack of a large power supply reserve, I can assure you that its large dynamic swings, plus its mid/deep bass weight and impact, are as good as I've ever heard. These qualities, plus its outstanding neutrality, immediacy and spooky silence, are what most impressed me about this unit. All of this was unexpected. The "standard" model of the ZYX pre-preamp has 20db of gain, with a slightly simpler circuit. It's very possible, if not probable, that it will sound even purer.

This is the step-up to get if you want superb sonics, complete background silence, with no fussing around and total cable compatibility. If there's a better head-amp around, I haven't heard it, or even of it, yet. Its selling price is $ 1,650, direct on Audigon, which is $ 375 more than the Bent Silver. This may be an issue for some. However, for those audiophiles who don't like any MC transformer, for whatever reason(s), the ZYX is a "no-brainer" choice, if it's affordable.

The Bent Silver still has greater potential, which is why it is in Class A, but I can't absolutely promise you that this potential will be realized in every system. For the most serious phono fanatics, meaning those audiophiles who are prepared to make every effort to optimize it, the Bent Silver continues to be my highest Reference and, it shoudn't be forgotten, it can never break down. Just don't forget the caveats I've posted.

It must be emphasized that I have not yet heard the Bent Silver or the ZYX CPP-1 at its best: The Bent Silver can still be loaded-down some more, and the ZYX's 20dB gain model has still to be properly auditioned. Both require either a more sensitive system, and/or a cartridge with higher output. This will all happen in the next few months...

The first ZYX UNIverse I will audition has a .48mV output (while the Airy 3 I'm now using is .24mV). I'm also receiving more sensitive amplifiers and speakers from Coincident Speaker Technology.

The more I think about this, 2006 is shaping up to be a truly major year for audio developments and its evolution.

The ARC was a pre-preamplifier that used 6DJ8 tubes as amplifying devices. It is one of the two best of its type ever made and is very well built. It is an excellent performer, but far behind the Expressive above, since it just makes this class. It can be improved with modifications.

The biggest problems with the MCP-33 is that the high quality, low-noise tubes (6DJ8s) it uses are not only difficult to find, but they also turn noisy quite quickly.

More Recent Information (3/05)- I received a letter from a reader who feels he may have solved the inherent problem of this component; tube microphonics. Here it is, with slight editing;

"After experimenting with various types of tube dampers and cones, I found that the spring suspensions made by Loyalty Sound of Alberta, Canada, could be the most effective cure for the noise problem associated with the MCP33. After supporting the MCP33 on a set of the Loyalty spring suspension, I found that there was no need to put tube dampers onto the 6DJ8 tubes.

These spring suspensions could also be used to good effect for supporting CD players. I have heard significant improvements in sound stage and even tonal balance after a friend of mine put a set of these suspensions to support his Marantz CD7, which build quality is already rather exemplary. It should be noted that however the spring suspensions must be carefully placed so that all three individual suspension is subject to a similar loading (which could be verified using a spirit level). Loyalty Sound offers different spring ratings (140 lb, 70 lb and 40 lb) for the suspensions. The suspensions I used for the MCP33 are of 40 lb rating. The spring suspensions, just slightly cheaper than the Goldmund cones, are quite expensive however."

Personal Notes- This letter almost seemed like an advertisement for "Loyalty Sound", but this reader is most likely unaffiliated with them, and he could be right, so I'm requesting feedback about these "springs" from any reader who has first hand experience with them. Also, despite this reader's judgement, I still feel that Herbie's Tube Dampers are a requirement for the 6DJ8s used in this unit.

The Classe was the finest solid-state "head amplifier" ever made (until the ZYX CPP-1 above). It was beautifully built, it weighed 35 lbs., and it even had a separate, heavy-duty power supply. The majority of phono-stages and step-ups of today are literally like toys compared to it. It had some (potential noise) problems with set-up when it came out because of the cables of its day, but that shouldn't be a problem now.

The sonics can be described as very clean, detailed and dynamic. It still had some transistor problems (some dryness, darkness and hardness), but they were more subtle than any other solid-state model. TAS, in its review (Issue 34), also mentioned some soundstage anomalies. I didn't find them to be a serious problem. It's a shame that no one today makes a modern, improved equivalent of this component.

This model will be hard to find, but it's well worth the search. It was designed by the original (and now former) owner of Classe Audio, Dave Reich, who was/is both talented and passionate about audio.

I first heard this transformer in my friend's system, where we compared it to the EAR MC-3 and the MC stage of his Audion Quattro. We both preferred it to the EAR, but we also felt the Quattro was still slightly better, overall. The TX-103 did have an advantage in the high frequencies when the music was loud and complex. It retained its integrity, while both the Quattro and EAR had problems.

I've now lived with the TX-103 in my own system for more than six months. When first compared to the EAR, it was slighty, though still noticeably, superior in transparency, immediacy, preserving inner details, definition and it had a lower sound-floor. They were basically equal in neutrality and in the frequency extremes. Since then, I have broken in the TX-103 using the helpful instructions from Thorsten Loesch. The improvement was quite noticeable, which means this transformer is now competitive with the Audion Quattro and the (Class A) Expressive Technology. (One of my associates will try to arrange a shoot-out with the Expressive and both the silver and copper TX-103.)

The TX-103 has one important practical advantage that converts into a sonic plus; it's output consists of a short (7") wire with a RCA male termination, which allows a direct connection into the phono stage without the need of an extra cable.

My TX-103 is a DIY copper version, but recently this company came out with finished models. According to their website, the copper version is $ 745 and the silver is $ 1,075. I expect to audition a finished model, including the silver version, in the next month or so. See Bent Audio, the North America distributor, in the Links File for more information concerning this component.

This worked very well for me, so I recommend it highly. This is what Loesch wrote, with a little editing:

"(The TX-103)... will require a substantial period of "forced burn in" to give it's best, simply because the magnetic core is huge and will not see much magnetisation with normal MC signals. Please consider connecting a CD-Player to the secondary (Output) of the TX-103 and then terminate the input with a low resistance resistor (quality uncritical), I'd say 27 Ohm when connected for 14db gain, 6.8 Ohm when connected for 20db gain and 2.2 Ohm when connected for 26db gain. Leave with a highly dynamic, wide bandwidth signal CD to play for a week or two. I would use music, but I'd expect pink noise to work well too."
Personal Note- While on a week's trip, I connected the signal (a tuner on a 24 hour "grunge" station) to the primary (Input) instead, and had great results. The rest of the circuit followed Loesch's instructions.

In Spring 2005, I received and began auditioning the Silver version of the Bent Audio TX-103 MC transformer. So far I'm very impressed with it. In fact, it may be as good, or even superior, to the (Class A) Expressive Technology SU-1 in a number of areas, though there are also serious concerns that will have to be addressed before it can be used in most systems. This component is unique in my experience, and presents a difficult challenge to optimize, but I feel the effort will be worth it. Here are the details.

The Bent Silver is probably the finest (potential) transformer I've ever heard, and that includes the Expressive Technology SU-1 mentioned above. The Bent Silver has superior speed, purity, immediacy, transparency and focus. It also "individualizes" the musicians better than anything I've heard, and it doesn't congest or homogenize when the music becomes loud and complex. It may also have the lowest sound-floor, which is my primary "weakness". More than any step-up I've heard, it sounds like "nothing" is there. However...

The Bent Silver has one serious problem- It lacks natural "body and weight". The frequencies that provide this sense and feeling are either attenuated or, more likely, the transformer is slightly "tipped-up" enough that this frequency range is reduced in relative level (though the Bent is NOT noticeably "bright", does NOT appear to emphasize "detail" and is NOT "cold and sterile"). Whatever the reason(s), it's a problem that will disqualify its use for everyone except those looking for a noticeably leaner sound. This creates a frustrating dilemma.

Normally, if a component has a frequency response problem, everything else being equal, I just pass on it, since it can only be used in systems that require that particular coloration; either for "taste" or for "off-set". This situation is profoundly different, because "everything else is NOT equal". Think about this- when you give up on the Bent Silver, you are also forgoing all of its (maybe) unprecedented performance strengths. This I will not do, because once these "performance strengths" (i.e. musical information) are gone, they can never be retrieved again in the playback chain. They're gone forever. This is unacceptable to me.

So my long-term project is to find a method to neutralize the frequency response problems of this transformer. I have a couple of ideas; one of them is extremely simple- experimenting with the loading; the other is more complex- experiment by changing (slightly) the RIAA curve of my preamplifier. My friend has an equalizer, which may help us. (I have tried a slight VTA correction, but that does not work.)

I promise not to "give up" on this component until I'm absolutely certain that its (maybe*) unparalleled potential can not be realized. Remember, I always look at the potential of a component, and not its "first impression". Optimizing that potential is the only method in the long-term process of creating a "great system".

*I wrote "maybe" because while I thought I was making all the A/B comparisons with the copper/silver transformers in a "static" system (a requirement for assigning responsibility), it turns out it wasn't. I had to change the bass amplifiers (involuntarily) a couple of times, plus I now realize (in early June) that the last V-Cap Teflon cap I installed in my preamplifier was not totally broken in. Still, the advantages I mentioned above were heard repeatedly whenever I changed transformers. It's the total system still breaking-in, and the slight "tip-up", that concern me at this point, making me now think it's possible, though it's unlikely, that I may have slighlty exaggerated in my own mind the degree of the improvement I/we heard.

Recent Note- I have to first get to the ZYX Airy 3 pickup and its matching head-amp. This should happen in November 2005. Once this extensive process is over, I will go back to the Silver/Copper Bents, hopefully with a system that is even more revealing and challenging to them. When it comes to this Silver Bent MC Transformer, "challenge" is the appropriate word for me.

These models were the finest moving-coil transformers ever made at one time, and the best I heard, overall, before the Expressive Technology came into existence. They had excellent sound; natural, detailed and dynamic, though with both of the frequency extremes rolled off a little.

It came stock with its own (4') output cables already attached, which was a strong advantage, but now it is a decided disadvantage. The cable's excessive length and (now) mediocre quality both compromise the Cotter's inherent performance. A competent technician must be found to remove and replace them with good quality RCA females, which would then allow the use of any superior phono cable.

There are different models of this transformer that have different input impedances. The model with the lowest input impedance (2L) is usually the most desirable version with current cartridges.

The Verion was the exact same transformer as the Cotter, before the name changed due to legal reasons. However, unlike the Cotter, no version of the Verion was ever offered with the lowest (L) input impedance, as far as I know.

FURTHER: The original Bryston transformer (black) was the exact same model as the Cotter, with just a different name and color. It was even built by Cotter.

However, the current Bryston transformer, with the model name TF-1, is a different design. Chris Russell, the CEO of Bryston, claims this model "has a wider bandwidth and 40% of the measured distortion of the Cotter/Verion unit." I am sad to admit that I haven't heard this unit, despite the fact that it is made in Canada.

The RWR is a MC transformer that is very similar in sound quality, size and shape to the Cotter. The Cotter is only very slightly better.

This model also has the important advantage of user switchable input impedance's, which the Cotter lacks. This could be an important feature for those audiophiles who change their cartridges on a regular basis. It is very rare and was built in Canada.

This is another transformer that is very similar in quality to the RWR above. It's also very rare and difficult to find.

Further- A reader has informed me that he compared this model to a Verion (Cotter). He felt that the Verion sounded "thin and harsh by comparison". He also commented that the Audio Interface lost nothing at the frequency extremes and had plenty of "body". In another comparison, this same reader felt that a different version of the Verion was much better ("a dramatic improvement"), but it was still not the equal of the Audio Interface.

Even if both of the Verions had an impedance "mismatch", the fact that the Audio Interface was equal or better to them is a very strong endorsement for this model.

The Klyne is a very good and versatile pre-preamp, and it’s solid-state! It is neutral and it retains the frequency extremes. This was the finest transistor head-amp before the Classe NIL came out, and it is very possible that it is still more neutral than the NIL.

It also has switches for both input impedance and a variable capacitor filter to "tame" cartridges with high-frequency peaks, which were common 20 years ago.

It’s somewhat dry and a touch noisy in comparison to the others. Their earlier model, the SK-1 was too noisy for very low-output pickups (below .4mV). This exact same headamp is also incorporated inside some of the Klyne preamplifiers.

I've lived with this transformer and I am impressed with it. I used it with a Shelter 901 within a system in which the entire front-end was new to me. Meanwhile, one of my associates also has some experience with it.

The MC-3 has 3 inputs, each with different gain and input impedance, and one output. The sound varies with each choice of input. I had no problem with hum and/or noise with it at any time. In fact, it is "dead quiet", at least in my system.

At its best, using the lowest impedance and gain with the Shelter, it is neutral and has excellent midrange naturalness, detail and dynamic force. The bass is also special, especially for a transformer, going deep and with detail and impact.

The high frequencies are also good, being smooth and clean, but there is a sense of a "rounding" of the tiny details which individualize music. This may be caused by either a roll-off or a subtraction of low-level harmonics (and other musical information) or both. One other problem is that this model doesn't have the dynamic "jump" or "shock" of the Expressive Technology transformer, though it is competitive in this area with other step-ups. The Expressive should be better, costing more than 3 times the EAR's price.

The "timing" or phase of the EAR is good, but it is not quite as precise as the Expressive, so the music isn't quite as intelligible, and the soundstage isn't quite as large or as focused.

This is the best value, in every way, for a step-up being made today that I know of. It may even be preferable to the other Class C models.

Further- I have since heard this transformer on an associate's system and I have also logged more hours on my system. I now feel that I can faithfully describe its performance. It is very neutral, and the frequency extremes are excellent, both are extended, especially in the bass. The dynamic qualities are also excellent. There are problems though...

There is a noticeable "drying" of the sound; meaning a reduction of low-level detail. You hear less definition, natural texture, "air" and "harmonics" developing and decaying. There is also a slight reduction of image size and focus; musicians are a little diffuse sounding.

It is still the finest MC transformer I've heard for the money, but it won't join the Class B models as I had originally hoped. (6/03)

I sold this line in the early/middle 1980's, and even owned one of these models personally for a time. They were all excellent, with full bodied sound that this company is famous for, and also less residual "hiss" than most typical tube headamps. The later models were a little more transparent, faster and cleaner than the original HV-1. Unfortunately, none of them were quite as immediate, clean, neutral or dynamic as either the ARC MCP-33 in Class B or the Counterpoint SA-2 below. They all used tiny 6CW4 Nuvistors instead of traditional 8-pin tubes, and I remember the circuit boards being suspended by rubber bands for improved isolation. I don't know whether or not these Nuvistors can still be replaced today.

Win Research- This transformer may qualify for Class B or even Class A ranking. Stay tuned and hope for the best, because it is far less expensive than the Expressive.

Counterpoint SA-2- This was a serious tube "head amplifier". At its best, it was one of the two finest ever made, along with the ARC MCP-33 above. Unfortunately, it had problems with reliability, hum and excessive tube noise. The (6DJ8) amplifying tubes had a tendency to become noisy in a very short period of time.

I had experience with two of the early models, and I was never able to keep them working, at an optimum level, for more than a week or so at a time.

The later models were supposed to be improved, especially in the area of reliability, but I am not able to verify this claim at this time. I would avoid this model unless there is an extensive audition or a money-back guarantee.

EAR- The early (1980's) EAR transformer was very large and heavy for its time, and it had extraordinary gain and dynamic qualities along with a "large sound" and deep bass, but it also had problems with noise, hum and even had some frequency irregularities. In the right (though unusual) circumstances, it could be superb, but this is another "try it before you buy it" component.

Koetsu- I was a Koetsu dealer for more than 10 years, and I had extensive experience with virtually all their cartridges and their moving coil transformer. Their transformer was expensive for its day, but then nothing from Koetsu was ever a "bargain". It was enthusiastically "hyped" by the Koetsu distributor before it was released.

The performance was mainly typical of the moving coil transformers of its day. It had an excellent midrange, definitely better than average, with good body and excellent retrieval of low-level information. The problem was the frequency extremes, which were noticeably rolled-off, especially in the bass. There was poor mid-bass impact as well. It was a big disappointment for me at the time.

In the final analysis, this was "a good" but overpriced and over-hyped component, that never lived up to its very high expectations. The fact that it is mainly forgotten today is its "testament".

Quicksilver- This was a small and modestly priced transformer. It was clean, smooth, quiet and detailed. It was especially impressive in the high frequencies, with extraordinary extension for a transformer.

Unfortunately, the bass was very noticeably rolled off and it was also dynamically compressed. Further, it was not quite as "rich" or as full-bodied sounding as the much more expensive Koetsu. It was still a good value, considering everything.

Marcof PPA-1- This was a unique battery powered unit that was popular in the early 1980's. It was very inexpensive and had "OK" sound considering the cost. Its main sonic problems were a relentless background "hiss", dynamic compression and a very noticeable dryness. This model is only for "beginners" or those on a really tight budget.

Shelter- One of my associates had this transformer in his system for a while. He said it was "decent", but not "outstanding", even for the money.

CAVEAT-Please be advised that the readers’ letters posted on this site are solely the opinion of that reader and may not necessarily represent or reflect the opinions of Arthur Salvatore or High-End Audio. These letters furthermore, are not to be taken as being endorsed by Arthur Salvatore or High-End Audio. They are posted because they may be edifying, thought provoking or entertaining.

BENT SILVER TX-103 TRANSFORMER- I recently received an e-mail from a long-time reader and contributor, Thorsten Loesch, with news of a different version of this superb transformer, plus other components from the same source. Here it is:

Music First Audio, a subsidary of Stevens & Billington, manufacture a fully featured step-up unit of my design around the TX-103 (silver is available on request), including switch adjustable loading and step-up, as well as a most excellent passive preamplifier based around transformers (again mostly my design - the background sketch on the front page is an early drawing of the circuit for it):

While more expensive than Bent Audio product by the simple fact that, unlike Bent's direct sales, Music First Audio Products are distributed through normal distribution and dealer channels; they do offer a different take."

Here's some useful information from a reader about tube replacements for this reference step-up.

"...I have been using/loving one for about a year now and thought you should know that the tubes (4 x 6CW4 Nuvistors or 6SD4) are very readily available NOS on ebay even today, and they are fairly cheap too, $10-$20 a piece. I am using 4 RCAs and the analog sound is really great, much better than any of the solid state stepup units or transformers I have tried (Naim, PS Audio, Denon etc). Another nice thing about the Premier 6 is the cartridge loading can be set internally with plug in resistors anywhere from 2K ohms to about 10 ohms. And yes, you were correct, the main circuit board floats via rubber bands to eliminate any possibility of tube microphonics messing up the sound....." (1/08)