RCM Audio Theriaa phono stage review



During the many years of trying to catch the audio bunny for as little money as possible (you do not believe me? It would be interesting where you would end having a big budget), I often had periods of being enchanted. It is widely known, that during the way up to the summit of the sound, you are always surprised by something. Every time it happens, some aspect of the sound reproduced brings us a step closer to our goal. But then there comes a moment, when we approach a glass wall, when we try to squeeze the last bits out of the new equipment and then … we give up, returning happily to that what we already had in our system. To keep it short – after hearing another novelty, we decide that the time to make changes in our system has not yet come, and after thorough analysis of all aspects we decide to wait, easing down the strain on our budget. Fortunately for myself (or at least for my home budget) I am at such a wall. I am not complaining, as it allows me to fulfill the list of wishes of my wife (and it is a long one…). But some longing to have something better, something more involving, something creating a better nirvana remains. However all the attempts to overcome this glass wall I was talking about failed, and the scratches on the wall blurred the view of the Eden behind it. So I would remain contented for a long time if not for…

Being a diehard analog fan I buy a lot of vinyl discs, despite my analog glass wall came much sooner to me than in my digital system. Maybe I became old and deaf, but despite the measurement results, higher distortion and required celebration, listening to vinyl really brings joy to my life. There is nothing better than spend a Saturday night with a glass or two of Ardbeg listening to a playing vinyl album. Even if people think, that this is a crippled sound source, every time you listen to it, you get your peace. In the fight of what is better, vinyl or CD, Christmas or Easter, I will always bet on the analog. The system I have, I own for a few years now, and being aware, that it is only of medium quality, I was totally satisfied with its performance, and directed my attention to bring the digital part of my system to completion. Unfortunately the quality of the digital source bared the shortcomings of the analog one. I started to listen to it much less frequently, and mostly just to quiet down after a hard week. It still had its unmatched smoothness and timbre, but the way the music was presented was worse than in my digital system. I did not think that it could happen that fast, but it did. Fortunately life does not stand still and ‘somebody is awake, to allow somebody else to listen’, and a novelty came to me.

I was in a kind of winter sleep with my system. Having a vinyl based system for a few years I listened to many different gramophone preamplifiers … with bad results. I tried to go forward, but the RCM Sensor Prelude stood its ground, against all possible contenders, tube and solid state, showing them their place, outside the door. So I was thinking that the only way to upgrade my system is to change the tonearm or deck. Having a tonearm made by the British company SME, I thought, that the easiest upgrade would be to have the turntable exchanged for one, made by the same company. Seems easy, but completing my digital system learned me, that I should avoid small steps, generating unnecessary spending. I try to jump over a few steps, to get something jawdropping. The only problem became the level of spending, which rose to a level creating fights with my wife… So I did not think about rising the level of my analog system. This lasted until I got a call from Mr. Roger Adamek, my analog promoter in a way, telling me about a new phonostage he designed, which kicks butt of many other products, including his former Sensor Prelude, and sets the threshold really high. So I had no other choice, than to confront the claims of the manufacturer and test the unit called Theriaa.

The courier arrived at agreed time and I received a substantially big and heavy package with something, that in most cases fits on a small PCB inside a receiver or amplifier. Feeling the weight of the package, I hoped this does not mean, that all the design went into the outer form, but that this is only a prelude to what awaits me sonically. So I cut the box open and inside I found two devices – the main unit in the size of an integrated amplifier and a smaller one, containing the power supply. The cabinet of the preamplifier is made entirely of brushed aluminum. The unit I received had the massive fascia in natural aluminum color (a black version can be ordered) and the rest of the unit was anodized black. The front panel is quite minimalistic, with only two rows of four LEDs on the left side, indicating the status of the phonostage for each channel separately, a milled strip dividing the front in the upper and lower panel (at about ¼ height) and the company logo and device name below it. I like such style, and it also fits the rest of my system perfectly. The back end of the device is typical RCM – a pair of input RCAs and output RCA & XLR sockets, indicating the unit is balanced inside. Additionally there are two microswitch rows per channel to set the gain and cartridge load, as well as a grounding pin and the socket for the power cable coming from the external power supply. The PSU is painted black and has only one LED in the front panel indicating operation and an IEC socket, power switch and a cable to connect to the main unit mounted on the back. Fortunately the cable is long enough to be able to hide the unit away from the preamplifier.

Using the same setup for years allows to immediately identify the changes brought by a new device plugged in, so I could verify the claims of the constructor. If the changes are for the better or for worse, this remains to be seen later, but from experience I know, that an immediate “wow” is usually a bad motivator for purchasing anything. There are ways to ‘catch’ inexperienced listeners with some tricks. Many people fall to those, what usually results in a wealth of second-hand merchandise being present on internet auctions, and minimizing the amounts available to really get good sound. In my case I was just to listen and to write a review, so I did not even think about buying the unit. I did not know, how wrong this attitude was, but about that later.

The phonostage came pre-burned-in, but I decided to give the Theriaa some time to warm-up the power circuitry, by plugging it in and keeping on without playing music. I knew, from available information, that the power circuitry of the preamplifier is very worked out. After about one hour I placed the first disc on the platter – I just bought in an antiquity shop a Japanese pressing of the free-jazz trio David Murray, Jack Dejohnette and Fred Hopkins called “In Our Style”. Buying only older issues, without searching for ‘first press’ editions I can keep my spending on acceptable levels. I listened for a few moments on my Sensor and then switched over to its bigger brother. Everything was clear from the very beginning. The new, reference phonostage from the Katowice based RCM did not want to base on the previously achieved fame, something often present in other companies, but had its own approach to the music. My favorite instrument in any kind of music is the saxophone. Timbre, saturation, smoothness, force of its sound in good recordings and replayed on good audio system are things that make me shiver. And usually this is the problem, because we do not have much to say about the recording (some labels do it better than others, so we may search for those) but the home stereo setup must be top notch. The mentioned disc paired with the new RCM made me realize, that the impossible just happened – I passed the glass wall I was talking about in the introduction. The front man of the trio is a sax player, and for the first time I could hear the wooden reed of the instrument. To date I could only hear the timbre and the saturation, without the ability to analyze the air flowing through the instrument. It is incredible how much information was hidden before me. Not by being inattentive, but because it was not reproduced from the disc. The new preamplifier from Katowice showed things, that I was missing when listening to my turntable setup. The Sensor Prelude had no micro-information, showed no air on the stage, and even the instruments were kind of thick, edgy; while the Theriaa handled that perfectly, bringing us to another level of insight into the recordings.

Such bonus from the first disc on the platter? Knowing about the deceiving techniques used by various manufacturers I started to confront what I heard with my disc library. I played a second album, third one… all of them showed, where are the differences between the two preamplifiers. The Sensor Prelude sounded with a very impressive, saturated, smooth, free and dynamic sound. It lacked some refinement, but the presentation of the sound stage and the delineation of musicians on it were great. All rivals I heard during the last years were doing it wrong, or at least less good. I will not call out the names, because in systems matching their price levels, they may be good, but putting them to test in extreme high-end showed their shortcomings. This is also the reason, that I always refrain from posting categorical statements. Switching directly from one preamplifier to the second one may push a beginner in the analog world to the Sensor, because the Theriaa played a tad quieter – despite the gain levels set to same setting – what resulted in an impression of lesser dynamics and drive in the reproduced music. This is how the comparison looked like on the solo Antionio Forcione piece from the disc “Antonio Forcione Quartet”. The guitar was sharply delineated, we could feel the power of the instrument and the quick and strong solo riffs on steel strings caught the attention of the listener. It was worse, when the rest of the ensemble entered with the same aesthetics. Everything was reproduced strong and with overly exposed edges. Catching this approach to reproduction of music defined the picture I wanted to get, similar to the one I achieved in my digital system. It was like with jazz musicians searching for a certain feeling during a concert, the newest product by Roger Adamek found it during playback. Microdynamics, gradation of planes on the sound stage to the sides and in depth, limited only by the walls of the listening room, palpability of the instruments and vocalists by placing them exactly on the spot in the three-dimensional space, readability and resolution of the treble are on an incredible and to date unreachable level. It seems as if we would learn to know each instrument from the very beginning. Starting with brass instruments reverberating without any grain and ending with the mentioned saxophone, where you can hear, and almost see, the air flowing through it, which gives it lightness and ease of playing even the lowest notes. Everything a diamond tip of a cartridge can extract from the groove is present, nothing escapes. It just gets amplified in a way that reproduces exactly the intentions of the sound engineers. If a disc is well recorded and mastered it will not allow for casual listening, because the music attracts the listener, serving a 3D spectacle, and that without the need for any 3D glasses. Frankly speaking, it was the first time I had such an experience using my analog system. It turned out, that the same thing I achieved in the digital field is also available in the analog. Hats off for the guys at RCM. I know, this review is maybe too exaggerated, but really, for a long time I had not had such fun using an audio device, and so much satisfaction. This is a mile-long jump in the technology of vinyl audio reproduction, one that I waited for so long, and one that I will need to wait for much longer … unfortunately my wife vetoed my proposal to buy it. The return to the old setup will be painful – I will not be able to listen to vinyl for a month or so… Maybe it will return to normal later. Unfortunately life is not a fairytale, and everybody has some things other than audio to take care of.

Nearing the end of this adventure with the RCM Theriaa, which reshaped my view on the analog technology, I want to share a few warnings with you. To hear what I heard and described here, you have to give the Katowice made preamplifier a chance, by providing it a proper environment. Half measures like a midrange audio system may result in its failure, and a negative, and very unfair judgment. You really need to have a high-end setup, with the digital part of it being close to the ideal, giving the needed palpability and three-dimensionality of the sound, that guarantees the visit of the musicians in our listening room. I will not set any price levels, but medium range high-end is absolutely a must here. Only then the Theriaa will sing. When you are tired from attempts to shatter the glass wall surrounding your system, you should contact Mr. Adamek. Even if the price turns out to be a hurdle you cannot overcome, you will still have a ride of your life, and the sound will remain with you for a long time. If, by any chance, it will not sing in your system – take it with you to me, and I will show you what it really can.

PS. Goodbye captivating black disc, welcome soulless digit. For some time, to ‘reset’ my mind, to forget the unsurpassed sound master. I hope, that when my wife sees my longing, sees my torture, she will not allow me to suffer too long.

text: Jacek Pazio
photographs: Jacek Pazio, Marcin Olszewski

Producer/Distributor: RCM

Price:9800 €

Technical Details:
Gain: 52 - 76 dB
Input sensitivity: 0.2 to 5 mV, adjustable in steps: 0,2 - 0,3 - 0,4 - 0,6 - 0,9 - 1,4 - 2,0 - 2,5 - 5 mV
Input impedance: 20 Ω - 47 kΩ, adjustable in steps: 20 - 30 - 50 - 100 - 200 - 400 - 1000 - 47 000Ω
Input capacitance: 100 pF
RIAA Linearity: +/- 0.1 dB (20 Hz - 20 kHz)
Input: RCA
THD: < 0.01%
S/N: 85 dB
Output Impedance: 70 Ω
Output Mode: Balanced via XLR or unbalanced via RCA
Nominal output level: 2 Vrms
Maximum Output Level: 9 Vrms
- 440 x 265 x 120 mm - amplifier unit
- 205 x 270 x 105 mm - power supply
Weight: amplifier unit - 9 kg, power supply - 4.5 kg
Shipping weight: 17.5 kg

The system used in the test, a complete set of Combak Corporation.

Electronics Reimyo:
- Separate DAC + CD player: CDT - 777 + DAP - 999 EX
- Tube preamp: CAT - 777 MK II
- Solid state power amp: KAP - 777
Speakers: Bravo Consequence +
Power cables: Harmonix X-DC-350M2R Improved Version
Speaker Cables: Harmonix HS 101-EXQ (mid-high section); Harmonix HS-101 SLC (Section woofer)
IC RCA Harmonix HS 101-GP
Digital IC: Harmonix HS 102
Table: Rogoz Audio
Accessories: Antivibration stand for the power amp by Harmonix TU-505EX MK2, Harmonix Enacom improved for AC 100-240V; Harmonix Tuning Room Mini Disk RFA-80i

Analog stage:
- Turntable:
drive: Dr. Feickert Analogue "Twin"
arm: SME V
cartridge: Dynavector XX-2 MK II

Original article link

Matej Isak. Mono and Stereo ultra high end audio magazine. All rights reserved. 2006-2013. www.monoandstereo.com. ..:: None of the original text, pictures, that were taken by me, links or my original files can be re-printed or used in any way without prior permission! ::..