AM AUDIO RT1 tube TVC preamplfier - 2 box

AM 02 PA RT1
NZ$ 7,995.00 ea (incl. GST)
AM Audio

The ultimate purpose is to be able to reproduce 'genuine music' not just detail


"Audio Music's AM RT1 (RT2) TVC valve preamp belongs into the top echelon of performance as do its assembly and finish quality."..... Srajan Ebaen (6MOONS)

The volume control system consists of a volume switch coupled to a volume transformer, that we produce and used for many years.

The benefit of this volume control is that the sonic background is very quiet and natural with a detail rich retrieval and a rich musicality that will clearly reveal every note of any piece of music.

We use a Single Ended design which is more natural sounding and dynamic than Balanced designs employed mainly for the studio environment.

The AM RT1 preamp is a dual mono design, from the transformers, power supply to the voltage regulation, all completely separated to avoid noise and cross talk. We use a large number of high value U-Cap copper foil capacitors, which were carefully chosen for their naturally detailed sound. The output transformers bandwidth will extend from15 HZ to 120KHZ

The unique design of our new tube preamplifier named "Magnetic AM R-T1" can be implied from the prefix: "magnetic", which indicates its direct origin from the AM magnetic passive preamp. Not only does AM R-T1 utilise transformers for volume attenuation, it also employs another two transformers for the signal output and two more for power supplies.

The remarkable level of performance has been achieved with an all new audio and power supply circuit design. This new audio circuit is all tube, Class-A, with zero feedback, utilising a total of four long-life tubes (2 x 6H30 as the drivers and 2 x 6922 as the amplifiers); and furthermore, it is a true dual mono circuit design in both the input and output stages, with the support of two volume control transformers.

The Magnetic AM RT1 is a direct upgrade from the Audio Music reference version of the magnetic passive preamp, which already delivers an exceptional performance over other similarly employed designs, by using both tube amplifiers and output transformers. One great advantage of this magnetic feature is that it is capable of optimally matching any power amplifier and interconnects, while accepting inputs from any sources of various impedance levels, with the least possible interference to the signal.

The power supply in the AM RT1 is also dual mono. The main power transformer, which is used to power the audio circuit, and Mosfets, that are used for both the voltage stabilisation and for a constant current supply. This enhances the reliability, and makes the tube amplification as linear as possible.

With its great build quality, audiophile grade components, versatility and the ability to musically transform any system, not only does the AM R-TI deliver striking clarity and detail that presents instrumental timbres and textures in an amazingly lifelike way, it also represents great value, with great reliability and stunning looks.





    • Two transformers for volume attenuation with 33 steps.
    • Transformer output.
    • Independent regulated power supply.
    • The left and right channels are a completely independent dual mono design.
    • Single ended tube Pure Class-A design with a zero feedback audio circuit.
    • Versatility to electrically match any source, amplifier and interconnects, based on a fully magnetic transformer implemented design.
    • MOS-FETS for voltage stabilisation and constant current supply.
    • U-cap capacitors in signal path.
    • Detachable IEC power cord.
    • High quality gold-plated AM custom binding posts and RCA jacks.TEFLON insulated wire
    • Japanese made POCC rectangular solid core copper wire all the way through
    • Precision matched aluminums alloy chassis and exceptional build quality


Tube complement: two 6H30 or 6H6N as the drivers, two 6922 as the amplifiers
Frequency response: 20 Hz ~ 100KHz
Input Impedance: 47k ohms variable depending on the source
Volume control: 33-speed volume control
Output Impedance; 600 ohms . RCA output & BAL output.
Input selections:   3 pairs RCA single-ended ; 3 pairs balanced / XLR
Gain:  Input 0.5V  / output 2.5V
S / N:    > 98dB
Distortion rate: under  0.5% / 5V
Power consumption: 45 watts
Dimensions 380W x 340D x 110H mm
Weight: 38 Kg shipping weight


The Audio Music RT1 (RT2) is an absolute giant killer in my eyes.
Dan Worth

REVIEW SUMMARY: I’ve never previously heard the decay of strings fade into such a dark background, especially on a live album so intrinsically natural, whilst the next leading edge saturates the foreground with precision and clarity. This all becomes so valuable when the wooden casket of the instrument itself can be heard as an extra resonating layer which fulfils a realism in the music, which I haven’t before heard any other preamplifier achieve in my system.

I could play bass from a passage of Bach, a track from a Damien Rice album, playful Jazz and Trad, or even Pop with a little Dance music thrown in and each time the grip drive and gusto for each music type was enthralling!

Mr Fang’s meticulous approach taken to the design of his products is truly reflected in the sound of this preamplifier. I am just so impressed with the level of performance obtained at this price point. The true impact and emotion coupled with intricate detail, timing and top end air simply put, proves itself time and time again with each and every piece of music I have thrown at my system.

EXTENDED REVIEW: The Audio Music AM RT-1 active TVC single ended valve preamplifier is made and designed by Mr A M Fang. It comes with a fine pedigree, but will it cut the mustard with Dan Worth. 

Audio Music evolved from the Stereo Knight brand of high-end, yet relatively affordable products. Designer and engineer AM Fang wanted to create a newer more vibrant company that pushed the boundaries of design and high precision engineering even further with a line up of products to rival some of the world’s greatest talents in audio reproduction.

Previous products from the Stereo Knight range were extremely well constructed and implemented with the preamplifiers being TVC based (Transformer Volume Control), many years of creative testing also demonstrated the brands knowledge to influence the design of valve based mono power amplifiers.

Today Audio Music have continued there pursuit of musical bliss with the edition of more complex and refined preamplifiers and passives, along with some serious looking 833 and 805 based mono power amplifiers.


There’s no doubt that when an AM product comes for a visit the courier needs to be a fairly large chap or have a trolley handy! In the case of this review product it’s the AM RT-1, a valve based preamplifier utilising transformer volume controls in a dual mono format, with a transformer coupled output stage. The courier was not expecting the answer I gave when he said ‘my god, what on earth is in here this time Dan?’ With me replying ‘just a preamp’.  The overall weight of the two units (one preamp and one power supply) is 38kgs! An absolute beast, that size wise only comes in at 38x31x11cm per unit.

Opening the boxes to get a glimpse of the two units was an unbearably exciting event. I’d studied many photographs of the preamp over the previous weekend admiring its build quality and beautifully thought out layout. To finally have the physical articles in front of me was a true joy.

The build quality is absolutely phenomenal, the attention to detail and accuracy of machining puts AM products up their with the very best that I have ever experienced in the high end world of Hifi, which is a world usually only ever inhabited by the purely unobtainable. Each panel is precisely engineered to the finest of finishes, internal boundary sections of machined billet are impressively accurate and each component and its wiring is of the neatest possible standard. Mr Fang should be truly proud of this accomplishment alone.

What are those big caps inside you say? Well, these are from a company called u-cap, not heard of them? No, nor have I. Talking to Iain Borthwick of lwaudio (UK Distributor) he relayed a short story which I would like to share – Mr Fang, the stickler for perfection that he is, decided that the capacitors on today’s market were not quite at the specification he would have truly liked, so what would any engineer/designer do in this case I ask you? They would contact one of the major brands of course and have capacitors made to their very particular specifications, surely?…. no, not Fang, he decided that along with meticulously winding his own custom transformers he would build a factory that would be able to produce capacitors to his exacting standards! Now in my mind that’s overkill to the last degree, but for Fang this is just another day at the office. The saying “if you want something done right, then do it yourself” springs to mind. I’m going to have to slightly change the initials to this mans name, AM Fang becomes AMS Fang (A Mad Scientist Fang), his efforts are pretty much unheard of today, every meticulous nut and bolt, cap, transformer, PCB layout, casing positioning is just phenomenally critiqued by Fang before us reviewers and consumers alike even get the chance to have a look. Really though, this level of attention to detail deserves applause.

Now, I hear everyone saying ‘yes, yes that’s all good and well Dan and we appreciate your candour but what does it sound like, does all the visual hype translate into equally exceptional sound quality?’

With a selection of three inputs, whether you opt for using the units assigned unbalanced XLR or unbalanced RCA inputs, a choice must be made for each of the three inputs available. My first instinct of course is to connect to the unit’s XLR inputs, but as the design is single ended and not truly balanced  it shouldn’t really matter. I only have the single ended DiDiT 212 DAC at the moment as the balanced version is in final stages before production and my pre-ordered unit will not arrive for a little while yet.

The RCA version of Studio Connection’s Platinum interconnects were plugged from DAC to pre, the same brand XLRs then trailed from the AM RT-1’s balanced output sockets rather than RCA as the Muse Reference 300 monos I’m using are much more comfortable running on balanced, even if pseudo for some unknown reason. My usual modded Ayon Seagull Ceramic speakers are in play and all of this fed from the modded Mac using various software for normal and hi-res audio playback, through the recently reviewed Hydra S and Chord’s Sarum Super Aray USB.


The first most clearly defined aspect of this preamp’s sound signature is true transparency, after a few steps on both mono switches whilst listening to Nils Lofgren’s ‘Keith Don’t Go’ I felt I was really hearing my system for the first time in all its natural beauty. I specifically picked this track to begin as it’s live, well recorded and needs a critical ear on leading edge performance, pace, and decay during the guitar solo off of the ‘Acoustic Live’ album.

I’ve never previously heard the decay of strings fade into such a dark background, especially on a live album so intrinsically natural, whilst the next leading edge saturates the foreground with precision and clarity. This all becomes so valuable when the wooden casket of the instrument itself can be heard as an extra resonating layer which fulfils a realism in the music, which I haven’t before heard any other preamplifier achieve in my system.

Transformer based volume controls have a nature of being transparent and great ones will produce a level of detail and timbre which can be hard to achieve from an active preamp, however they can have some pitfalls. Drive can be a little weak, also grip and control can suffer, trading these aspects slightly for natural tones and detail retrieval generally outweighs any shortfalls for most enthusiasts.

The AM RT-1 takes all of the best aspects from each of the topologies and runs with it. Transformer volume switches to improve the noise floor, a single-ended valve stage to increase dynamic range and tone and critically wound c-core transformers with mosfet voltage stabilisers for drive and grip on some of the most demanding basslines makes me wonder what on earth some are missing from their designs.

I could play bass from a passage of Bach, a track from a Damien Rice album, playful Jazz and Trad, or even Pop with a little Dance music thrown in and each time the grip drive and gusto for each music type was enthralling!

I especially loved how the influence of popular music from across the decades sounded as each track from a playlist would be discernibly different… as the playlists are from various artists. Each track had a character of its own and my own system’s signature, or house sound, disappeared and was replaced by music that had a relative tone and position with more truth to the mix. Each recording could be explored further than when using my Jeff Rowland preamps which add a characteristic warmth and body to the sound.

Equally remarkable is the soundstaging of the AM RT-1. I really appreciate how different genres are protrayed, giving a more realistic perception of a performance, especially with live music, where I felt I could place each member of the group more accurately and each band members instrument had its own void to emerge tones from that was never disjointed from the music as a whole and remained utterly focused in its own free space.

Levels of excitement built drastically over the follow weeks, where I found myself listening to music more than I had done for a long while in my own personal time. I’d find myself getting up in the mornings and listening to the main system before I left the house and likewise when I came home again, I’d even just leave everything turned on whilst I was away from home so that when I arrived back I could have a fully warmed up system to just sink into.

A strong curiosity with the AM RT-1 was, if it sounds so utterly mesmerising now, how will it sound with a careful valve change? The valve compliment used in the RT-1 is two 6922/E88CC and two 6H30P. The hunt was now on for the best sounding equivalents in this circuit. The 6H30P tubes, which are the Electro Harmonix gold pin version were swapped out for the only real possibility, the early 80’s model, legendary Russian Reflektor 6H30P-DR ‘Super Tubes’, which were incredibly hard to source and cost a small fortune. After some competition the 6922 valves I settled on were the USA made Amperex White Label, which bring a more organic flow to the mids and give a more dynamic bassline, again difficult to source and quite pricey but the way things were going with my time courting the AM RT-1 I could see us having a long and loving future together.

How gorgeously the vocals developed in tonal balance and natural dynamism after the valve upgrade left me mesmerised by every piece of music I played. I have only ever heard such fluid and liquid vocals like this once before with Lampizat0r equipment, but the AM RT-1 had no fear of breaking down and is built like a piece of fine jewellery, so in comparison its material wealth was simply greater. Coupled with the units subtle, sultry, dynamic, fast, gritty, deep and delicious characteristics that exuded from my transducers I felt very flattered to have found this brand.

There’s the cliche ‘it’s like someone has lifted a veil’. I could agree with this in terms of transparency and insight but to try and convey some more meaningful context to the sound, my analogy can only be stated as a difference between watching a high school play compared to that of a Broadway show, the raw emotion and power in the performance gives the AM RT-1 true believability.

I laughed to myself, thinking back to when the AM RT-1 first arrived some two months ago. I had just placed the units on the rug in my living room, side by side waiting for my friend Richard to come over. Richard is a DIY enthusiast and has some very interesting equipment. I knew as soon as he walked in he would just stop and look at the units then turn to me and offer that grin of acceptance he does when something pretty catches his eye. How correct I was, however I didn’t expect him to sit cross legged on the rug for a good five minutes just turning the witches backwards and forwards, but there you go. Fortunately they are of superb quality and this over exuberant wear and tear didn’t phase the solid build one little bit. He then spent the next twenty minutes along side me just glaring into the custom made and engraved acrylic lids Iain Borthwick of lwaudio had got custom made to show off all the lingerie the electronics was adorned in.

Well, Richard was here again today and we both spent some time listening through a great range of West African and Asian music which he is very fond of. It’s the first time my ever critical friend has remarked at how natural and full instruments sounded, with areas of micro dynamics which belie the very room we were listening in. I pointed out to him that centre focus was no longer as prominent and although the central soundstage was so well defined and characterised he needs to have a seat in my sweet spot to really enjoy how the stabilisation of imagery has now grown to include all areas of the soundstage in height and width, giving more maturity and insight into what is a true full picture or image of the performance, which I felt my previous preamps did well, but in hindsight barely scratched the surface and he agreed without hesitation.

Mr Fang’s meticulous approach taken to the design of his products is truly reflected in the sound of this preamplifier. I am just so impressed with the level of performance obtained at this price point. The true impact and emotion coupled with intricate detail, timing and top end air simply put, proves itself time and time again with each and every piece of music I have thrown at my system.

Every venue is accurately portrayed, each note is produced with body and the story told within each piece of music, whether containing vocals or not, is emotionally connective. I can only speculate the improvements of the models further up the line, but right here, right now the AM RT-1 is the very best (by quite a margin) preamplifier I have had the pleasure of having in my system and there is no chance of it going back to the distributor, even if it’s the only one he has in stock.


The Audio Music RT1 is an absolute giant killer in my eyes. The brand offers another two incarnations of the design which take the performance even further. Firstly an RT-2, which, is an RT-1 that has all silver wiring throughout, then the RT-3, a silver wired dual mono power supply like the previous two models but this time you will receive three boxes rather than two, with more isolation and tweaks to power sections.

Performance of the AM RT-1 is absolutely natural and emotionally engaging, having me listen to more music than I have in a few years. I currently have lots of other activities which I am enjoying in my life and finding some real solid time to just sit down and have long listening sessions has not been as easy as years gone by, but I am finding myself making time to change this and my listening sessions have been becoming more frequent since the Audio Music AM RT-1 arrived and my listening has included many albums I haven’t listened to for a very long time… as well as the enthusiasm to find and listen to new music.

The standard unit was a dream to behold, but the addition of the specially selected NOS valves really enhanced the RT1’s natural abilities to reproduce timbre and vocal complexity.

Already the soundstage was a triumph, but the additional valves made instrument placement more accurate in sense of timbre and naturalness, whilst also pushing the layering of venue acoustics and reverbs to the next level. The base unit will amaze even the most hardcore audiophile, but with these careful choices in play sonic greatness is achieved.

For my musical tastes, which are vast and varied, good solid state amplification coupled to the cleverly implemented valve line stage of the AM RT-1 suits my needs absolutely perfectly.


Sound Quality: 
Absolutely stunning, liquid midrange, very dynamic bass and a bandwidth that combines inner and upper end details with emotional insight and clarity.

Build Quality: 
Will compete with a lot high-end offerings and surpass many, absolute precision and quality inside and out, with a meticulous view on circuit and component implementation.

Value For Money: 
The AM RT-1 is a fairly costly preamplifier, but in the realms of high-end prices the RT1 is a bit of a bargain.

Highly detailed natural sound
Naturally dynamic and transparent
Emotionally communicative
Timbre rich

Only three inputs may not be enough for some
Lack of remote could be a problem for some

Audio Music's AM RT1 (RT2) TVC valve preamp belongs into the top echelon of performance as do its assembly and finish quality.
Srajan Ebaen

SUMMARY: Audio Music's AM RT1 (RT2) TVC valve preamp belongs into the top echelon of performance as do its assembly and finish quality. It might take a few more years for this new reality to sink in. The few adventurous souls open-minded enough to already give this machine an audition should simply agree that this future is here now!...

EXTENDED REVIEW: At the Munich HighEnd 2013 show,a properly British chap introduced himself as Iain Borthwick, procurer of fine hifi to the royal crown. Well, not exactly. But his expressive gushing over the Audio Music two-box AM RT1 preamp could have aroused even the blue bloods. In short, the designer of the previous Stereo Knight Silverstone passive magnetic preamp I'd reviewed a few years back had parted ways with his former partner James Zhang, gone solo and launched a new brand. AM AUDIO. Iain had not only signed on as dealer/importer for the UK but as a global marketing liaison of sorts. 

Like the earlier one-box Enigma preamp under the StereoKnight banner, the now twin-chassis AM RT1 combines 6H30 drivers and 6922 voltage gain bottles with a custom 33-step magnetic volume control using multi-tapped step-down transformers. Whilst it does lose the relay-switched remote volume—said to be in the works again—and manual volume is dual mono, Iain's enthusiasm over sonics and build quality flooded right over any such piddling inconveniences. Having kissed off valve amps, my remaining glow Jones is on preamps. The man's timing and delivery thus were spot on. Do me and that. A month after the show a broken-in unit was available to hop, skip or pop across the Channel.

With a ship weight of 37kg, there'll be no real hop. Schlep is more like it. Or a small pop in the lower back. With 20Hz~100kHz bandwidth and >98dB S/N, this is clearly a serious machine. 600Ω output impedance on RCA/XLR isn't excessive but far higher than my equally tubed Nagra Jazz's 50Ω.

A hefty smattering of U-cap copper-foil capacitors should lead the resourceful to some digging and shortly this statement: "We're a factory that has made tube electronics for more than ten years. These include silver-wound volume transformers, dual C-core power transformers, C-core output transformers and different types of capacitors. Due to the high price of genuine copper-foil caps from Jensen, AudioNote and V-Cap TFT, we decided to produce our own." Listed as U-cap's general manager is aka Audio Music. That too is resourceful. The still up StereoKnight website isn't. It injects confusion about directly competing products from the same pen. So I asked Iain—who was proper game as befits his marketing efforts for AM Audio.

"StereoKnight was one of my best-selling brands. They consisted of two partners. One designed and made the products, the other was responsible for promotion & sales. They'd been working on an all-new mono amp design for some time before they closed due to the global financial crisis. The two partners went their separate way but Fang the designer since perfected his new monoblock and formed a new company. He also has a new balanced transformer-attenuating preamp released as a StereoKnight model shortly before that company closed. There's also an all-new balanced preamplifier based on the previous quite awesome StereoKnight Enigma. 

Design and internal layout look very impressive but the minimalist exterior leaves me with some reservations so keen as I am to try it, at the moment I've not purchased one."

Lack of remote, numerical display, clear input socket and selector markings admittedly make the AM R1 seem a tough sell. On paper. If Iain Borthwick was right—his name conjures up a kilted gael daring you to disagree—sonics would undercut any such hesitations. Yet not all agree that superior sonics couldn't or shouldn't be accompanied by modern features. Personally I'd thus not particularly consider a preamp without remote. But since I knew going in that this one didn't have one, I couldn't bitch about it now. You obviously are under no such obligation. 

Iain Borthwick:
"I hear what you're saying about the confusing nature of StereoKnight's website still being live despite having no product to sell. According to Fang their sales stopped in November 2011. But since James was in charge of the site Fang can't take it down from his end. Fang asked me to explain his rational behind the new Audio Music preamp. He states that it is a
reference design, hence the dual volume controls, separate power supplies, transformers and voltage regulators and his custom 20 copper-foil capacitors. He feels that his old method of remote control via relays was detrimental to ultimate sound quality. At the moment how he wires up his volume pots would necessitate a very powerful motor to actuate them mechanically. It's something he's working on. This circuit is not truly balanced as that would entail four attenuation transformers. Fang claims that the sound is better single-ended so that's what he went with.

This thematic—yawn—is quite common for perfectionist designers who'd rather have you sit on a bed of nails than sacrifice an iota of performance you'd never know about. They pass on responsibility for overcoming objections and getting beat up about lacking conveniences to their (few) sales agents. From the above Iain Borthwick was perfectly aware of it all. That he still felt representing this machine was worth his time and effort during these early days either tells us about his pigheadedness; the sound of the terribly named Audio Music R-T1 preamp; or both. Let's simply say I was intrigued enough to remain signed up. Another reason was that the 6H30 tube here isn't used as output but driver triode. 

In my 11 years at this helm, I've never before come across a component this deserving of being called built like a tank. Think Burson squared. The canned TVCs are braced in massively machined aluminium retainers. So are the output and power transformers. The vertical tube board mounts its super-tight sockets to a massive aluminium plate whose back side doubles as mount for the associated circuit board. The grooved heavy-duty top cover locks into rabbeted place with eight long bolts passing with perfect fit through the overkill corner blocks. Whilst one might rightly question whether this type of build is necessaryI don't think that Jeff Rowland shoppers would though—there's no question that Fang, Audio Music's designer is an extremist when it comes to mechanical construction. By necessity this means high mass to make this one of the heaviest preamps to ever have crossed my threshold. What in this context might disappoint is the supplied tube complement of electro-harmonix 6H30Pi and 6922. High-volume valve gear makers must for obvious reasons rely on current production tubes which for more affordable gear means Russian or Chinese.

Once we get to the bespoke low-volume level at which today's contender clearly means to play, one expects more particularly when it comes to the ECC88. Here the R-T1 goes hoi polloi.

If you've ever wondered about manufacturers referring to components as true dual-mono whilst running off a single power transformer with dual secondaries, Fang would have your back. He even extends this divide-and-conquer thinking to his stout doubled-up 4-pole umbilicals; and as we already knew the twinned volume controls where it arguably gets just a tad inconvenient but does double as precision balance control. 

If the audio signal is nothing but modulated power supply, their supply should have us feel in very good hands indeed. Needless to say, such design intensity has to include completely noise-free operation both mechanically and electrically for zero transformer hum and nada tube rush. The AM RT1 complies. 

Ambitious tube gear which claims that noise is acceptable as long as the sound is good belongs into the past century with wow and flutter and brickwall filters. This wrapped up the visual inspection of this flawlessly executed hardware.

Wired up to the Goldmund Job 225 stereo amp with 35dB of gain, I drove Boenicke Audio's B-10 speakers off my usual Metrum Hex converter preceded by SOtM's best two-box battery-powered super-clocked USB bridge. The first thing I noticed was gain. Or rather, insufficient attenuation at click one. At the whisper levels I use during late-night workouts, I needed an extra 6dB signal cut. This I sourced through PureMusic's 64-bit dithered digital option. Hence with a high-gain amp coupled to speakers, listening distance and room size of sufficient 'efficiency' against very low playback levels, max attenuation might not be max enough. Granted, 26dB gain amps are rather more common than my 35dB job. For many this may be no issue particularly if they never listen very quietly. 

The first sonic surprise was just how loud the AM RT1 sounded at micro volumes. We're all familiar with hifi's mandate that escalating volumes ought to only go louder, not change with band-specific compression, stridency, brightness, hardness or other nonlinearities. Hardly anyone talks about the inverse. Things shouldn't collapse, shrink or disappear as volumes fade. It's probably a fortuitous combo of current drive, overall system resolution and speaker responsiveness that delays the inevitable sonic shrinkage which accompanies counter clockwise on the dial. Old-fashioned loudness controls were meant to compensate for HF/LF loss at pianissimo levels but none of today's high-end gear has them. Here the R-T1 set a new high in low. It maintained truly phenomenal intelligibility and substance all the way down into the very ambient noise floor of the room itself. 

If you think on it, there's something very wrong with being held hostage by systems which only satisfy when played loud. Sometimes loud isn't appropriate or possible. Sometimes you're not in the mood for it. Should you settle for a lesser experience then or, worse, opt to not listen at all? If you relate, the Audio Music preamp up-ends such silliness (obviously your particular amp/speaker interface must be capable of transferring massive signal cut into proper fullness and detail - and many speakers just aren't). Very likely Fang's magnetic volume controls had something to do with this due to how effective their lot get as one turns them down. 

The upshot is that contrary to popular lore where tube circuits are inherently noisier than transistor equivalents to come second on resolving power, on low-down intelligibility with body the AM RT1 thoroughly whupped ass on my Esoteric C-03 preamp and even outweighed my Nagra Jazz in the bass.

This segues straight to our core appeal today. Usually mass is the enemy of transparency. Load up on mass, go lighter on see-thoroughness. Increase lucidity and watch weightiness fade. One of the balancing acts anyone actively involved in assembling a hifi system must walk is deciding where exactly on this scale to be. With the AM RT1 in the loop one gets to move up on both weight and lucidity in lockstep. That's not normal but very productive and beneficial. The effect is quite akin to printing out a colour drawing in speed mode with spent cartridges particularly the black one versus selecting superior slow mode with fresh colours. The former will be faded and pale, its lines inconsistent. The latter will show maximal contrast with fully saturated lines and extreme legibility. Resolution and impressiveness—how the lines impress/imprint themselves on your senses—go up. And that's exactly how the AM RT1 asserts itself. It handles resolution not by emphasising transients or sharpening outlines. To coin a term related to dynamic contrast, it manages heightened resolution with material contrast as the difference between space that's empty and space that's taken up by seemingly material substance.

This makes for a different flavour of presence. It's not constructed on the basis of perfectly timed accelerated transients and the dynamic frisson and jump factor derived from it. It's not primarily about the transmission of energy then. It's an equally tacit but different sort of presence. To borrow from Starship Enterprise's transporter beam, it's built on beamed-downiness completed with a few extra moments on the molecular reassembler. It's quite uncanny and light years removed from common tube gear dialogue on harmonic distortion and temporal flexibility. None of that factors. In those terms it's a perfectly realised transistor sound albeit with very uncommon material contrast. With my reference Nagra—whose remote response, volume taper and zero-gain option combine into the ultimate user interface—I'd call the qualities to register first space followed by textural elegance. This doesn't mean you hear more or less. At this level it's only about a different perceptional perspective, not about the contents of what one perceives. The contents are fully realised in either case. The musicians play all the same notes.

This 'all there' of course included my magnetic passive Tap X from Bent Audio which played up the lucid aspect. At very low volumes meanwhile the resistor-based Khozmo passive with remote clearly shrunk, faded and paled to act inarguably subtractive by comparison. Even at regular levels that passive couldn't muster the same profoundly substantial conviction of the Audio Music. Whilst otherwise sharing TVC technology, the Bent too came second here to perhaps demonstrate the active circuit's trump card in the robustness stakes.

To my mind there was no doubt. Fang's reference ambitions weren't egoic talk or aloof navel gazing but plain fact. On sonics and build if not features the AM RT1 was true reference caliber. 

This makes the asking price quite a deal. Chinese origins and popular yellow fever don't factor. Nor do tubes per se or 'pedestrian' Russian stockers in particular. If we apply popular expectations the 6H30/6922 combination sums to solid state but categorically eliminates the minor glare and dryness the 6H30 routinely exhibits on its own. You'd be hard-pressed though to generate this level of nothing-to-something contrast with transistors. The use of valves thus doesn't seem frivolous or accidental. As the offset between empty silent space and dense tone fill those bottles do something, just not what most might expect.

With my Goldmund Job 225 amp, many have wondered. Is the relative lightness of its power supply related directly to the amp's lucidity and speed? Such thinking suggests that an overkill power supply could lead to ponderousness. In Audio Music's apparently overkill case I heard none of the latter if we exempt bass. It wasn't slow but ultra butch. Nagra's PSU for the Jazz would fit into Fang's casing 10 times or more. It could seem like an underdeveloped joke but the sound is anything but. As a matter of fact the Jazz played it more lit up, impulsive and quick. In the end and purely on aural feel we might say that if you prefer Yo-Yo Ma go Jazz, if Mstislav Rostropovich think AM RT1.


The AM RT1 should be of particular interest to people of either hi-eff systems where deep attenuation is the order of the day; or those who routinely listen quietly but presently belabour a significant loss of substance whenever they do. Here the transformer-based volume controls excel at maximising drive at very low signal voltages. It really was just a matter of time. Reference Chi-Fi has arrived. 

Audio Music's R-T1 TVC valve preamp belongs into the top echelon of performance as do its assembly and finish quality. It might take a few more years for this new reality to sink in. The few adventurous souls open-minded enough to already give this machine an audition should simply agree that this future is here now!
..….. Srajan Ebaen

The R-T1 (R-T2) presents a sound quality that betters anything else this reviewer has yet tried. .....the R-T1 is simply a no-brainer.
Paul Messenger
REVIEW SUMMARY: The R-T1 (R-T2) has the sort of transparency I’ve come to associate with the simplicity of valve-based circuitry, made all the more impressive here because background noise was invariably totally absent. Stereo imaging is another major plus. Leading edges seemed particularly well defined, helping to deliver the contributions of specific musicians – and indeed the musicianship – with great clarity, and this was further enhanced by the fine timing and dynamic expression which are all inherent elements in the overall package. 
EXTENDED REVIEW: It had to happen: China has definitely caught the audiophile bug. And since Chinese manufacturing costs are much lower than those in the West, it’s starting to become possible to find genuine audiophile products that cost much less than those made in the UK or the US. A typical example is the Audio Music R-T1, a two-box valve preamplifier that weighs an extremely hefty 38kg, due in no small part to its extensive use of transformers. 

Visual inspection and internet browsing provide quite a number of clues to the background, purpose, and heritage of this preamp and its Chinese audiophile protagonist. The company began in the 1990s, so is a relative newcomer, which is no great surprise in view of China’s recent history. As I understand things (and the situation seems to be murky at best), the company’s products were initially sold under the StereoKnight brand, but a subsequent parting of the ways led to the recent founding of Audio Music, to market the products designed by Am Fang of Guangzhou in South China (a very large city some 120km north of Hong Kong). UK distribution is being handled by Iain Borthwick of LW Audio, and the copper-wired R-T1 is currently being sold at £5,500. Two more costly variations on the R-T theme are also available: the silver-wired R-T2 costs £7,500 (NZ$12,995), while a silver-wired three box R-T3, with a completely separate power supply unit for each channel, is priced at £10,000 (NZ$17,250). 

The R-T1 was actually developed to improve upon the Stereo Knight Enigma preamps, and is clearly a component with serious audiophile aspirations, as borne out by the unit’s double-mono construction and minimalist features set. Designer Am Fang used reference capacitors such as Audio Note, V-Cap, and Jensen in developing the U-Caps that are made in his Mexican factory, while the power supply and volume control transformers are all built in-house by Audio Music. 

The three knobs on the front consist of two volume controls (one for each channel), based on discreet-step transformers, plus a central triangular switch that selects one of just three line inputs. (Remote control? Don’t be silly!) The only other decoration consists of three tiny green lights: one indicates ‘on’ (whether or not the valves have been inserted); the other two show (rather faintly) the settings of the volume controls. 

The R-T1 is therefore not big on convenience features, provided of course that three inputs are sufficient to suit one’s lifestyle. The three inputs use single-ended RCA phono sockets in parallel with balanced XLR sockets, so at least this is an option, as are the similarly flexible output socket pair. However, it is big on audiophile appeal: besides using transformers to adjust volume here, two valves are used in each channel – 6H30s as drivers and 6922s for voltage gain – and out of preference the desing uses single-ended circuitry throughout. The valves do mean that the unit runs slightly warm to the touch, but quoted power consumption is just 45W. 

Assessing the R-T1 proved an unexpected challenge. When I initially powered it up, the little green light came on, so I left it for a few days to run in, and was then surprised to get a null result. Downloading the on-line manual revealed that I needed to open up the preamp unit and install the four valves, which had been carefully wrapped for transportation. Once inserted, running in could begin again! (a timely reminder to read the manual).

Switched transformer volume controls do lack the fine discrimination of continuous potentiometers, and this is particularly important when listening at very low, late-at-night levels. That ‘jamming’ problem and its consequences made it impossible to assess accurately the discrimination of the 33-step transformers used here, but ad hoc estimates (using just the left channel) suggest that things are likely to prove generally satisfactory with typical sources, amplification, and speakers. Although switched transformer steps do inevitably limit discrimination, low level results did seem acceptable. 

I got down to some serious listening and was immediately and profoundly impressed by its sound quality. Where to start? Perhaps by stating that it sounded clearly superior to my usual NAC552 (complete with Discreet Regulator power supply) in most respects. Superb transparency was one immediate observation. 

The R-T1 has the sort of transparency I’ve come to associate with the simplicity of valve-based circuitry, made all the more impressive here because background noise was invariably totally absent. Stereo imaging is another major plus, keeping individual instruments well separated in their own spaces, and delivering them with fine focus and excellent impressions of depth and surrounding space. 

Leading edges seemed particularly well defined, helping to deliver the contributions of specific musicians – and indeed the musicianship – with great clarity, and this was further enhanced by the fine timing and dynamic expression which are all inherent elements in the overall package. 

I soon found myself re-exploring my treasured vinyl collection, and discovering subtleties that had previously been obscured. Vocalists’ accents and inflections were that much more obvious, sometimes even bringing fresh layers of meaning to lyrics, and individual instruments seemed to be highlighted to the point where they became not only much more obviously identifiable, but also that much more communicative, too. Even the inevitable noise floors associated with vinyl seemed significantly lower than expected, perhaps because of the very impressive overall dynamic range that this preamp invariably seems to deliver. 

A colleague recently reviewed Audio Music’s single-box and much less costly (£1,950) R-S passive controller (which also uses transformer-coupled volume controls), and reported excellent results. Past experience has found that passive controllers are impressively neutral and transparent but also lack a little dynamic vigour, which was also reported in the aforementioned review, so this is likely to be the essential sonic advantage of the R-T1 over the R-S. Certainly there’s no way one can criticise the R-T1 for any shortfall in dynamic drama and expression, while the extra physical content of this active and powered valve-equipped preamplifier more than justifies its higher price. 

I was intrigued to find that this preamp even made it possible to distinguish between three different versions of the BBC’s 2014 Glastonbury TV coverage: truly live (albeit rare) transmissions; recorded performances that were being broadcast live; and transmissions that I’d recorded onto a Humax hard drive recorder. The overall sound quality I get from TV is well below that available from other sources, but it was still possible to detect the distinctions between these three transmission and recording modes, even though the differences were decidedly subtle. 

TV sound is all very well, but the best pleasure invariably came through listening to the best sources, especially the many vinyl discs that I dug out from a copious collection. Many hadn’t been played for a number of years, and these often proved a source of rediscovery and mostly delight.

Despite a price tag that is well below today’s high end norm, the R-T1 sets a remarkably impressive sound quality benchmark (and presumably the R-T2 and R-T3 do so too), so on these grounds alone Am Fang deserves the heartiest congratulations. 

The R-T1 presents a sound quality that betters anything else this reviewer has yet tried. For those happy to live without remote control, and with a choice of just three inputs, the R-T1 is simply a no-brainer. +......
....…..Paul Messenger