PMC cor integrated amplifier
“It is designed not to do anything” said the nice man as we discussed the arrival of the PMC cor integrated amplifier at Kelly Towers. He went on to explain that the design philosophy behind the cor (and yes, it meant to be all lower case) was that it should be as free of its own sonic signature as could be achieved. Of course the ‘straight wire with gain’ amplifier has been every designer’s dream since the phrase was first coined by Peter Walker (Quad) more than half a century ago. Since then, many great audio designers have pursued this elusive goal, some with more success than others. The challenge here was to see how close the PMC engineering team has come to that goal. Before we get into that however, let’s check out the cor itself.
It is a pure Class A/B design, and is quoted as delivering 95 Watts into 8 Ohms and weighs in at 12kg and is of typical integrated amplifier scale, it fitted on to my Quadraspire XL shelf very comfortably.
This is not the first time that the PMC cor has been reviewed on the Ear, René van Es gave it a glowing write up in 2017 shortly after launch, but I am in the market for a new amplifier and the editor recommended I try this distinctive design from the transmission line speaker specialists at PMC.
As you can see from the pictures, the front of the PMC cor has an array of six buttons on the left which are marked cd, radio, av, aux, bal 1 and direct. Again no upper case anywhere on the fascia except for the company logo at the bottom left. The logo glows white when the amplifier is switched on and red when it’s in standby mode. A white LED below each button lights when that input is selected. Next to it is the IR receiver for the remote control, which must have a clear line of sight. Three sliders are marked balance, treble and bass and next to them are three more buttons marked mono, mute and bypass respectively. When these are in the central position a white LED is alight beneath the slider control. When a slider is moved in either direction the associated white LED turns red. Below them is a headphone socket, which mutes the loudspeaker outputs when a full size (quarter inch) jack is inserted. The amplifier stays muted after the headphones are unplugged and the user must unmute manually. Last, but by no means least, the motorised volume control, which also (hallelujah) has a white LED to show where it is set. All these functions can be controlled from the extruded aluminium remote handset, which sits nicely weighted in the hand and which is well laid out. I felt at home with it within minutes.
Analogue and proud
This a proudly analogue-only device, so no DAC, no digital inputs. It is designed to take an analogue signal and amplify it for your loudspeakers to play for you. I happen to think that is still the smart approach, as there is no DAC to be made obsolete by next year’s new model. The PMC cor is guaranteed for five years but I suspect that for many buyers it will last a decade or more at the heart of their system. The French for heart is of course le coeur, not a million miles from cor. Make of that what you will.
The review amplifier was finished in black, but silver is available if preferred. The finish on the case work is matt and seemed highly resistant to fingerprints. The PMC cor happened to arrive not long after a pair of Node Audio Hylixa loudspeakers had been installed in the listening room (full review to follow soon), and thus they were the only loudspeakers used for this review. The rest of the system was my own Linn Sondek LP12, with a Dynavector XX2 cartridge fitted to the Ittok arm, a Gold Note PH5/PH10 PSU phono stage and my Yamaha CD-S-3000 SACD/CD player, which also does DAC duties for the TV and an Auralic Aries Mini streamer. Power distribution is through the excellent Shunyatad Hydra block, with Shunyata mains cables for the amplifier and the source units (except the Aries Mini, which has an iFi PSU driving it). Other cabling was Tellurium Q.
Listening to and living with a PMC cor
It has taken far longer for me to write the above than it took for me to get to grips with the cor. It is easy to use, helped greatly by the very solid remote control, on which the buttons are well laid out and after a little practice, easy to locate even in a fairly dark room.
The early listening sessions were carried out with music streamed from Qobuz, both as hi-res files and in CD standard 16/44. In combination with the Hylixas the presentation seemed absolutely free of artificial additives. The cor adds no character of its own to the music, it simply amplifies the signal from whichever source is deployed at the time, so the better the source the better the sound. In this case it made clear that my diminutive Auralic streamer, while a very adequate performer, would be better suited to less revealing amplifier and loudspeakers, and for the rest of the review period I stuck with silver discs in the Yamaha and the (mostly) black ones on my vinyl replay system.
SACD fared very well in this set up. I played some of my favourites like Love’s Forever Changes, on the Mobile Fidelity Sound Labs release, in which Arthur Lee’s complex arrangements came through with admirable clarity, defying the 56 years that have passed since the album was recorded. That was followed by the terrific SACD rendition of Pink Floyd’s Wish You Were Here, which some argue was that band’s finest work. Presented in this format and heard through the cor/Hylixa pairing the soundstage was enormous and each member of the band’s contribution was easy to hear and appreciate. Switching genres, I loaded The London Double Bass Sound on the Cala label; I have a soft spot for music created on the largest instrument in the string section. This is a very fine recording of an interesting potpourri of music, arranged for massed basses, two of which feature Gary Karr as guest soloist. The highly revealing amplifer/speaker combination really allowed me to hear into the recording, naking it easy to discern the different instruments playing in each piece.
Switching to vinyl, it quickly became apparent that here was a system that would allow me to really hear what the complex replay system (cartridge, tone arm, player and phono stage) were doing, and I am pleased to say that it was exceptionally good. I played vinyl versions of the Love and Pink Floyd albums and it was fascinating to move from the forensic presentation of SACD to the slightly more organic sound of vinyl. Neither was better than the other, but they were definitely different. Since the cor is equipped with tone controls I played around with them from time to time, but that was more because I could than that I felt the need. The tonal balance of the cor with the tone and balance sliders dead centre is so good that for the vast majority of the time that was the preferred setting.
In the evening, when my daytime listening room reverts to its alter ego, as a room in which we can relax and watch some television. The Yamaha DAC is used with an optical connection to the television. Everything we watched sounded as good as it looked, with PMC cor/Hylixa team delivering dialogue with impressive realism, and uncanny accuracy in matching the voice to the character’s position in the frame.
PMC cor conclusion
The PMC cor undoubtedly fulfils its designers’ goal. It is possibly the least characterful amplifier I have had in my listening room, which is perhaps the highest praise than I can give it. Pairing it with the Hylixas was perhaps fortunate, given that they too are the least coloured loudspeakers I have had in the room, and the combination worked so well together. Given that the Hylixas retail for about six times the price of the PMC cor it shows that sometimes price is not the only criterion for figuring out what equipment combinations will work best together. When I used to think of PMC, I naturally thought of loudspeakers, where they are a major player in both the home and the professional markets. Now that I have met the cor I must think of them as great electronic engineers too. The PMC cor is undoubtedly an exceptional amplifier, which never got flustered even when hooliganism trumped safety in my use of the volume control. This is a seriously great amplifier, and I hope that more of you get to hear it and enjoy it as much as I have. It is as close to a straight wire with gain as I have yet heard.