REVIEW OF SIMON YORKE AEROARM by Michael Quinlan,January 2010
First let me declare my interests. I am a vinyl enthusiast. Have been for almost 50 years. The last 20 of those years I have used Simon Yorke turntables. I bought an S2 Zarathustra second-hand in 1989. It replaced the Linn I had used for 10 years and wrought immediate all-round improvement to the music. A fortunate find indeed; SY made only twelve S2s. Then in 1996, having made contact with SY buying spares for the S2, I learned he had a new turntable that marked a major move from sprung suspension to mass isolation: S7. I bought one as soon as he could build it, with SY unipivot arm. It tightened the sound right across the frequency spectrum, sharpened the image, cleaned up the HF, and removed LF overhang I didn’t know I had. In short, a massive change. After the Linn and the S2, life was simple; no going out of ‘tune’, no messing about with springs and bounce. It was set and forget; just put a bit of oil in the bearing every two or three years. I ran that system until last autumn. I would have been entirely content with S7 as my last turntable.
Some years ago, SY mentioned to me he was working on a parallel tracking arm. I was immediately interested. A parallel tracker offers important advantages a pivoted arm cannot. As well as the relatively minor benefit of eliminating tracking error, it mimics the geometry of the cutting head but most importantly it allows a huge reduction of arm beam mass that should enable increased compliance with the groove, thus making the sound ‘faster’. However, the few designs that had reached the market never fully overcame the difficulties of engineering the bearing. As a result those designs now populate a backwater – all top arms in current production are pivoted. SY had long held similar views, although he acknowledges he has been thinking about a parallel tracker for many years. The actual development of the Aeroarm occupied more than five years, attested to by a large box in his workshop containing scores of now-silent discarded components. Experience of his other products told me that when it finally appeared his arm would combine engineering excellence and aesthetic elegance. It would be likely to represent a big step forward soundwise. I made up my mind I would have one.
After keeping me quietly informed of progress from time to time, in spring 2009 SY informed me he was about to launch the Aeroarm. I wanted to put it on my S7 but SY said his S10 is a worthwhile advance and I ought to listen to it. In retrospect he feels the S7 had been a bit over-engineered and its solid and massive steel platter might ring and be responsible for some blurring of the signal. Without going into detail here, the S10 platter is of lighter sandwich construction combining the steel flywheel with layers of aluminium and graphite providing far better damping. So it was in July that my Van den Hul Colibri and I visited SY to have a listen. Putting Aeroarms on both S7 and S10, he set up my cartridge on an Aeroarm carriage that is easily switched between the units. We listened to a mixed batch of LPs. Whilst the contribution of the new arm to the S7 was immediately only too obvious, as between the turntables I did discern a definite reduction in bass overhang and some tightening in the high treble. Not an earth-shattering difference in my view, but a worthwhile one. In addition, visually the S10 is a more modern design and matches the Aeroarm better than the S7. Its slimmer reconstituted white stone baseboard imparts a complementary, lighter, look compared with the thick black slate S7 base.
I drove back from Spain with three large boxes in the car: the S10, the Aeroarm and an air compressor to drive the arm bearing.
Set against its clear advantages when compared with a pivoted arm, the Aeroarm does have a few drawbacks. Its air bearing requires a steady supply of clean compressed air. In the past some air bearing arms have been powered by small fish tank compressors that might be sited locally to the turntable. SY doesn’t see things that way. He specifies a MainAir compressor, made in the Netherlands and mainly intended for medical applications. With the size and appearance of a small generator, it weighs 25kg and kicks out far more power than the Aeroarm could possibly need. It has a reservoir that provides the required pressure for more than four minutes after it has been switched off. Such overkill may be daily bread for SY, but it isn’t an object that would look good in my living room. Thus was hatched a plan to site it in the basement below. But the nearest suitable accessible location is some 20 metres from the turntable. Worse, below the living room there is a 10 metre crawl over bare damp rock with only about 70cm headroom above. Plus I needed to find a way to get the airline and control cable through a foot of concrete and marble living room floor without waking my wife with the drilling. First off, the job would have to wait until the autumn as the summer heat would make working below ground unbearable. That gave me plenty of time to think about ways of getting the lines through the floor. October came and several attempts to pull them through the conduits feeding dedicated AC to my system proved abortive. But in the end the penny dropped: run them through the central vacuum system pipe that has an outlet conveniently located for the turntable and the vacuum motor close to the chosen compressor site. I tied a bit of rag to a string and inserted it in the pipe at the turntable end and let the vacuum do the work. Rag and string duly appeared at the other end. Lines pulled through, five minutes, sweet as a nut. Now the vacuum pipe sucks dusty air one way while inside it the compressor line now blows clean air in the opposite direction! But we don’t listen to records and run the vacuum simultaneously. It only remained to set up compressor and turntable and wire everything up.
Being familiar with the S7, the turntable was speedily done with the arm already installed on its board with correct geometry for the S10. Another Aeroarm drawback is levelling. Whilst it requires no bias adjustment, an air-bearing arm is fiendishly sensitive to the slightest gradient. It is essential to get the turntable level, especially laterally in the line of the beam supporting the carriage. SY now sells a purpose built turntable stand designed by his son Spencer. A very nice piece indeed. But my set-up is a heavy slab of stone standing in a large fireplace on the stone floor below and thus directly on the house foundations. When I conceived it in 1998 for the S7 I regaled SY with this ‘infinitely mass-loaded’ installation but he did not seem particularly impressed. So to level the new turntable he kindly made up small turntable plinth supports with a screw height adjustment at the right hand side, enabling fine adjustment of level laterally.
With the arm, SY provides a board with compressor control gear on it. I added a switch to power up the remote-sited compressor. I know nothing of compressors but SY’s clear instructions made it simple to connect it all up and adjust the air output to the specified level. My Colibri was still on the carriage SY had set up in Spain. A big advantage of the Aeroarm is quick interchangeability of ready set-up carriages and cartridges. Nevertheless, after slipping it on the beam I still checked all the geometry with the protractors provided and the tracking force. With the on-the-fly VTA adjustment integral to the arm I set the pillar height to level the cartridge carriage as recommended. It is quite remarkable how the smallest touch on the carriage sends it sliding right to the end of the beam, confirming the superb implementation of the ultra-low friction bearing. The Aeroarm is brilliant at tracking badly warped records, a function of its very low mass – at a mere 68 grammes its carriage weighs less than 1/4 of the beam of a typical 9 inch pivoted arm. At 50mm long it is 4.5 times shorter, endowing moments of inertia reduced by surely an order of magnitude. All this, as we shall see, permits the immediately obvious speed of its sound. It is also interesting to watch the carriage oscillating on the beam driven by the groove of a severely off-centre pressing. A Beomaster 4000 this is not!
The third and final Aeroarm drawback is the need for careful dressing of the leads to the carriage to ensure they exert the minimum force on it. The fine Litz signal leads are not much of a problem and are just draped loosely above the carriage over the top air bar. Although fairly compliant the latex airline must be carefully aligned in the plane of the beam and twisted on the fixings at each end such that there is no torque or tension in the line. That done, the acid test is on an uncut disc (supplied). Starting the turntable and dropping stylus on disc, the carriage will immediately run one way or the other, or perhaps different ways at different positions on the disc. I soon discovered the finest calibrated spirit level is of little use. The best way to level the turntable (and particularly to dress the airline) is to run the blank disc test while adjusting the height screw beneath the plinth. When it is level, the carriage will hold (or nearly hold) its position at any point on the disc.
Having already been in possession of the Aeroarm for some four months I could hardly wait to listen to it. We all start with a record we know very well in order to obtain a referenced first impression of the hoped-for improvements. For me this is always ‘Blonde on Blonde’. Featuring towards the top of almost every top 10 list of best albums ever, the sound is other-worldly even for Dylan, a strange blend of blues, rock and jazz. Some may pooh-pooh this as a stern test of a system but it is far from the two guitars, drums and bass of the Zim’s mid-60s contemporaries. These are dense mixes of up to nine instruments, including Dylan’s groundbreaking combination of piano and organ whose first outing had been just 10 months before on Highway 61 Revisited.
Particularly I listen to ‘Visions of Johanna’. Stage left are the acoustically voiced rhythm guitar, string bass, a quiet clipped and damped electric rhythm guitar keeping the beat; on the right most of the drum kit and an ethereal organ. Vocal and harmonica are centre, where just to the right on verse two enters the loud but sketchy lead guitar tuned for richness and treble attack. Only the best systems are capable of resolving all this in pitch, in rhythm and in space. Equipped with the Aeroarm my system achieved all this better on Blonde on Blonde than any I have heard.
I moved on to the Decca originals of Mahler’s Symphonies with the CSO under Solti. Everything is as is should be. In complex pastoral movements, the many voices are picked out individually with full clarity. Loud timpanies are pin-pointed in position and speed. Air can be heard moving through the brass. Basses rumble realistically of wood and resin. Bouncy, stringy and woody in the opening of Symphony 2. The latter realism is well confirmed on Casals’ Bach cello suites on EMI from 1938, in mono of course,
After feeling the weight of the timpanies in the Mahler, I figured Stravinski’s Rite of Spring might test the system more crucially in that regard. The best recording I have is the Cleveland Orchestra under Maazel on Telarc A 1980 digital recording at 50k/16bit, I have no idea why it sounds as right as it does. The short build-up and longer decay of the large bass drum impacted viscerally on the room.
Between 1977 and 1987 Gilbert Rowland recorded the entire Scarlatti harpsichord works on Keyboard, a small private label. These now unobtainable recordings are very detailed and open and sound simply and close-miked. The Aeroarm revealed the immediate attack of the plucked strings, the fast-fading high treble harmonics as well as the mechanical sounds unavoidably emanating from the action of the instrument with an almost dissected clarity I didn’t hear on the S7/pivoted arm. It strikes me a harpsichord demonstrates the speed of this arm very effectively, allowing each note to build up and fall away in little more than an instant as one can hear from a seat close to the concert platform.
Summing up, my notes reiterate ‘clean, clear, clinical, immediacy, speed’. But most of all, speed. In four months a lot more of my records have been carefully manoeuvred under the beam of the Aeroarm. Some of them have been opened up in ways I had not previously heard. All have been rendered with a clarity and apparent accuracy that confirms my confidence that vinyl at its best is at least the equal of any retail qualified digital media including SACD. It really is nothing less than remarkable that the skills of the engineers at Decca, EMI and elsewhere achieved standards of reproduction that all the lauded advances of the last 60 years have not been able to better.
Once set up and running, there are just a couple of niggles about the Aeroarm in use. In comparison with the usual forward downward movement to lower the stylus, the lift is counter-intuitive, operating upward and backward. Once known, quickly learned. The beam runs out low down across the disc surface and the centre spindle seems unnecessarily tall. A touch of a playing surface on either hard metal object spells a quick death. Records have to be very carefully manoeuvred between the two. I may be handicapped here, having lost binocular vision to childhood measles, however this is a definite but unavoidable issue on this arm. The job is best achieved by stopping the turntable, although time adds confidence and one becomes lazy. Too lazy on one occasion, I damaged an important but fortunately replaceable LP. That spurred me into action. I fabricated a cup-shaped fabric cover for the end of the arm beam, protecting records that should accidentally make contact. This is short enough to cover only the area outside the inner stop for the carriage and seems to do no harm. SY should consider supplying a cap of interference fit from suitable material that presents soft to the record but causes no harm to the finely machined and polished beam.
SY supplies the Aeroarm with two carriages. Each carriage comes locked in an aluminium ‘hanger’ that protects it and any cartridge attached to it. In view of the magic of immediate interchangeability, there might be a temptation to order more carriages. This is of course perfectly possible, but the internal sleeve is carefully machined to an interference fit on the beam and carries the airways, so the price is not trivial. SY’s transit packaging is superb. Engineered from pre-cut layers of polyurethane foam, each part is fully isolated and protected within an outer container of two successive boxes.
Not a simple product to own and operate; the Aeroarm will repay care in use, attention to the lengthy instructions provided and a certain amount of mechanical sympathy and common sense. Like all SY pieces, fit and finish is impeccable. Not only that, to my eye there is an elegance of form and suitability for purpose. It also seems to engage well with the best of modern standards of design and visual presentation. The machining and standard of engineering is superb; even as a static exhibit the Aeroarm would be a joy to own. Used correctly, I am sure it will operate faultlessly for more than one lifetime.
For me a big part of the enjoyment of owning SY’s products is the satisfaction of being able to support a world-class small artisanal business and to know besides being state of the art the equipment I am using was made by his own hand. As SY emphasises, in the modern world such opportunities are becoming ever more rare.
Very strongly recommended.
Van den Hul Colibri Gold
Audio Research PH2
Audio Research LS5
Krell KRS200 pure Class A monoblocs, upgraded by Krell to 400 watts each.
Kimber cable, mainly silver
Whole system run balanced
Copyright Michael Quinlan January 2010