Tom Evans Audio Design Groove Anniversary MkII
Tuesday, September 8, 2015
MC Phono Stage
By Jason Kennedy
Tom Evans has been making his Groove phono stages for some time now, the anniversary in this particular model’s name refers to 20 years of them and that occurred in 2010. Having been there at the start with the Michell Iso, which was effectively the first Groove and shared the black acrylic case that continues today, it doesn’t seem like 25 years but you can’t argue with a calendar. Tom’s shtick is that the best way to achieve true high resolution with vinyl is to lower the noise floor on the phono stage, the quieter this crucial part of the amplification chain is the wider the bandwidth and the more you will be able to hear. He advocates spending more, a lot more on the phono stage than the cartridge because no matter how good a cartridge is if the amplifier is noisy you won’t be able to hear what it’s doing. I have to agree, in fact I once took an Audio Note Japan stage (about £2.5k at the time) to a friends house who had a £60 moving magnet on his Thorens turntable, the improvement was staggering, the extra resolution revealed more music than you would imagine a modest front end could produce.
The reason for this is the level of gain that a phono stage has to apply to the signal in order to bring it up to a level that a regular amplifier can work with, in the case of a moving coil cartridge it’s in the range of 600 times. Which means that any noise in the gain stage is amplified by this amount as well, so a good phono stage needs to be somewhat quieter than the apocryphal mouse. For the latest range of Groove phono stages Tom has upgraded the silicon that achieves this amplification to what he calls Lithos 7.4, this has prompted a MkII series across the five Groove stages in the range.
What Lithos 7.4 has achieved in measurement terms is to reduce distortion and increase dynamic range compared to earlier models (existing Grooves can be upgraded to MkII). Tom likes to point out that dynamic range doubles and distortion halves as you move from one model to the next in the range, which would suggest that the entry level Micro Groove X is pretty noisy and distorted but I doubt that is the case. Not if the midrange Groove Anniversary is anything to go by at least, it is I suspect the quietest phono stage I have ever used but it’s far from the most expensive.
The other change brought about by the move to MkII is the introduction of adjustable impedance, previous Grooves have been factory set at one impedance and while you could specify what this was it was a bit limiting if you changed cartridge. Now there are dip switches on the back panel that are relatively easy to access; some stages have them inside, others underneath. Here there are eight switches in parallel that have an inverse logic to their operation, the more you turn on the lower the impedance, so switching them all on gives 112 Ohms, all off 1kOhm, with seven steps in between. Once you have grasped the basic tenet of the approach it’s easy to experiment with loading, and surprisingly easy to figure out which gives the best result once you start listening to the timing and the interplay of musicians.
With the Rega Apheta 2 (on a Rega RP10) which specifies 100 Ohm loading experimentation revealed that the Groove Anniversary’s 250 Ohm setting initially gave the best leading edge definition, power and cohesion of the various instruments on Tom Waits’ Swordfishtrombones (Asylum). The track ‘Underground’ has some superb musicianship and this stage makes each player’s contribution easy to follow whilst presenting the ensemble as a perfectly integrated whole. You can appreciate the timbre of the heavy tympani and the tiny sound of a plucked ukulele, not forgetting the glorious vibe playing of Victor Feldman. The space created by reverb on the following track ‘Shore Leave’ is massively evocative as is the percussion and terrific guitar break, all of which is presented in a full width image that breaks the outer bounds of the loudspeakers.
I put on Burnt Friedmann and Jaki Leibzeit’s Just Landed (Nonplace) for a bit of low end action and found myself enjoying the tune rather than the sensation of having my internal organs vibrated. Here the emphasis was on the sound of the instruments and the melody rather than the crunch, which made me wonder whether the higher than recommended loading might be affecting the balance. This turned out to be the case, the higher the load (on this cartridge at least) the less low end power it delivers but the faster the transient edges. Experimentation with a few other bass strong records made a case for bringing it down to the 200 Ohm setting. It’s nice to have such close alternatives.
With the finesse of Jocelyn B Smith’s direct to disc cut Honest Song (Berliner Meister Schallplatten) the quietness of the Groove is made obvious by the way finger clicks are so clear in the background of piano and voice. "The ‘air’ around the cymbals and the singer’s breath on the mic coalesce with the music to present a degree of realism that’s rare". Cymbal work is notable on a number of pieces and reveals an unusual degree of transparency but don’t get the impression that this is a lightweight filigree specialist. When the rhythm section on Patricia Barber’s ‘Company’ (Modern Cool, Premonition) gets going you know all about the power and pace. The double bass has a physical presence that is palpable but does not smear the voice and the acoustic it’s recorded in.
I reviewed a valve powered phono stage from a well regarded brand during the Groove’s tenure and made the mistake of comparing them. The result did not favour the valve stage one bit, making it sound noisy, smeared in timing terms and lacking in transparency. Valves cannot hope to be as quiet as transistors but people value the tonal richness they bring, I prefer to hear what’s on the record, the actual sound of the voices and instruments rather than what in photographic terms sounds like saturation. I also like the natural way that the Groove presents imaging, every record you play has a slightly different character which seems to be a logical result of the variations in recording venue and technique.
Take Leo Kottke’s Great Big Boy (Private Music) as an example, this is an acoustic guitar led band with voice that has an awful lot going on on tracks like ‘Jumps Up Running’. I’ve played this many times but had not been previously aware of the keyboard line, "the Groove cleans up the background and brings a coherence to dense mixes" that lets you hear right into them. It prompted me to listen longer and louder than I have for some time with this particular record, remember just what a great musician Kottke is thanks to the Groove’s its remarkably light touch.
Forget your Vendetta Research and Audio Research preamps, they may have legendary status but technology moves on and today’s silicon is infinitely quieter than it was only five years ago, which means you can hear more music and less electronic intrusion through it. The latest Groove Anniversary is a goalpost moving phono stage that digs deeper into the signal and reveals so much detail across the board that you can hear right into the layers of multitrack recordings. It still doesn’t help the musically inept like myself establish the time signature of Steely Dan’s ‘Show Biz Kids’ (Countdown to Ecstasy, ABC) but it lets you hear how each of the instruments in the mix was played and the irony of the lyrics.
Calm is the good word when describing the Groove, it takes everything in its stride and no matter how dense the material never seems to struggle. It’s a very low distortion conduit to the musical joy that vinyl offers. It won’t turn mediocre recordings into amazing ones but it will let you hear more of what has gone on in the studio or on the stage when they were made. It gets you closer to that place in time and space where the magic happened. "The only disconcerting thing is that there are several better stages in the Tom Evans Audio Design range", you have to wonder if there are enough superlatives to go round?
Resistance settings: 112, 126, 144, 168, 200, 250, 333, 500, 1000 Ohm
Capacitor settings: 100, 200, 300, 400, 500pF
Gain to suit cartridges with between 0.2mV to 0.6mV output (or custom to order)
Dual mono layout, dual Lithos 7.4 local regulators
Size HxWxD: 88 x 330 x 185mm
Weight: 2kg + power supply
See the review on their webpage.