Technics SP10 mk2
Price: £449.95. motor unit only
reprinted from the March 1977 edition of Gramophone magazine
Manufacturer: Matsushita Electric Trading Co., Osaka, Japan. UK distributor: National Panasonic (UK) Ltd., 107/ 109 Whitby Road, Trading Estate, Slough, Berks., SL1 3DR.
This new turntable unit from Technics represents a quite definite bid by the brand (the top quality hi-fi section of the Matsushita organization) to go straight to the top of the market in terms of technical performance. The fact that it has gone to the top in terms of price too (except for an occasional piece of exotica like the Gale GT2101 which costs over £1000) will not have escaped the notice of keen eyed readers.
The market for such high priced audio units is necessarily restricted to a few wealthy dyed in the wool hi-fi enthusiasts and the professional users who demand superlative performance together with great ruggedness and a number of specific operational features. The performance criteria for a turntable unit (without pickup arm) can be summarized as dead accurate running speed independent of changing mains supply or mechanical loading, low wow and flutter, low rumble and a massive platter in association with a main bearing capable of maintaining the given standards of performance for many years of heavy usage. The specific operational needs of professional users include adaptability to suit any good quality pickup arm available now or in the foreseeable future, quick start and stop, suitability for back cueing of exact notes in the music and a range of speed adjustment.
Except for the omission of any fine speed adjustment facility (only available on the professional ep version), the Technics SP10 Mk II would seem to meet or exceed all these requirements. A quartz crystal provides a fixed frequency reference unaffected by temperature or other changes, for the high frequency signal generator. A frequency divider circuit reduces this according to the speed selected, 33 1/3, 45 or 78 rpm and stores the information in a speed change digital memory. For control purposes, a push pull electromagnetic frequency generator is incorporated in the platter drive motor. It generates a signal whose frequency is a function of the rotation speed so that a phase control circuit can make continuous comparisons with the control signal and lock the rotation of the platter to the chosen drive frequency.
In fact two control signals are applied to the drive circuit in full wave configuration. This doubles current efficiency, gives quick response and a large starting torque (6kg/cm) and can be used to produce drive in either forward or reverse direction. Thus, when the unit is switched off, reverse drive and a mechanical brake work together to give very quick and smooth stop action (within 0.3 second). A half braking force is maintained in the stop condition to give smoother setting of a cue by ear. The frequency divider also supplies a signal to the stroboscope neon lamp via a circuit which shapes the signal digitally resulting in extra sharp illumination of the 190 stripes on the platter rim.
The massive diecast aluminium platter is 32cm (12.1 inches) in diameter, weighs 2.9kg (6.41b) and has a moment of inertia of 380kg/ cm2 (130lb/in2). Despite this, the rated running speed is achieved within a remarkable 0.25 seconds. Speed changing is effected in a fraction of a second also, the three selector switches each incorporating an LED (light emitting diode) indicator. A particular feature of the Technics SP10 Mk II is its ability to maintain correct speed under any load conditions. The handsome accompanying booklet whimsically remarks "If 500 tone arms of 2g tracking force were placed on a record at the same time, the turntable would still maintain each rated speed".
At the heart of the system is the latest brushless DC direct drive motor (Technics pioneered this system and supply DD motors to many other manufacturers.) And the all electronic servo control system has made possible a further bonus: a remote stop/start switch is supplied with a 240cm (8ft) cable. I dare say this cable could be lengthened at will, to extend the instantaneous operation to any convenient point in a home or studio installation.
Packing of the turntable is exemplary and its appearance defies criticism. The motorboard plate is a one piece brushed aluminium block measuring 36.85cm (14.1 inches) square and standing 2.9cm (1.1 inches) proud of the motorboard. There are absolutely no fiddling projections so that keeping the unit clean is a simple matter. The only controls are the large square stop/start button and the recessed speed selector buttons with their LED lamps and strobe window. All controls are at the front left hand corner just where the studio operator would choose to put them, and well away from the pickup arm area. The only supply required by the unit is a DC voltage and this is generated within a separate power unit housed in a rather large black case with 76cm (30 inch) connecting cable.
The rubber turntable mat has been made electrically conductive to inhibit the ill effects of static charge on records and a second rubbersheet is fixed to the underside of the platter to damp out vibrations.
How it performed
Specification and test results
|Speeds (rpm)||33 1/3, 45, 78.26||accurate|
|Motor type||brushless dc, phase locked servo, direct-drive||-|
|Wow and Flutter % at 33 1/3 rpm||0.025 rms
|Turntable diameter (mm)||320||320|
|Turntable weight (kg)||2.9||2.9|
|Pick up arm||n/a||SME 3009/II used|
Heeding the manufacturer's instructions to use durable and heavy material for the motorboard and just a little alarmed by the terrific starting torque of the machine, I used the template drawing to cut out the required holes from 3.5cm ( 1 3/8in.) thick plywood. This had to be obtained by bonding two thinner panels of plywood together. At the same time I made a cut out to take the SME 3009/II pickup arm and mounted the board on firm legs to be placed on the slate bed I use for all turntable or cartridge test measurements. This done, the unit performed well up to its technical specification on all counts. I am bound to say that my nervousness about spurious vibrations being set up by the quick start action seemed to have been unnecessary. In practice the stop/start action was beautifully smooth, even with the stylus in the groove, and the speed of control met its `twinkling of an eye' claims.
Insulation against outside vibrations or acoustic feedback was excellent. I tried repeating the loading demonstrations I had witnessed in Japan and elsewhere with this machine, of pressing down hard on a record with a Watts Preener or similar cleaning pad, and was again astonished to find that the speed remained true. Therefore a Dust Bug or extra heavy pickup would simply have no effect whatsoever on speed. Since the stroboscope in this machine, however superbly designed, is simply giving a reassuring indication that the platter rotation speed is in agreement with the quartz crystal derived drive, I felt it necessary to check with a separate stroboscope and our (hopefully accurate) mains supply. The result was complete agreement.
Measured drift was virtually zero and wow and flutter was so low, about 0.04 % peak weighted DIN, that I became persuaded that I was merely measuring the amount recorded on my test discs. Subsequently Roger Furness, of the UK agents for Technics, was kind enough to let me have a couple of lacquer test records specially cut to contain lower levels of inherent wow and flutter than is normally attainable. With these I found the SP10 Mk II to produce no more than 0.025% peak. Similarly for rumble measurements I tried all the usual test records and, though the lowest reading obtained was -48dB unweighted, this too was at the lowest limit of the discs' capability. As for mechanical noise, this turntable can best be described as silent: even with an ear close to the unit there is no audible running noise. I know of no unit which can beat this one for silent running.
To sum up, the Technics SP10 Mk II has a superb technical specification which it meets on all counts. The craftsmanship and design skills lavished on it have me reaching for all the superlatives. Except that there would be odd occasions where I would miss the ability to make small speed adjustments for individual records, and an autostop would be useful, this turntable is a joy to use. Professional users should welcome it wholeheartedly. The home enthusiast will obviously be very conscious of the high price. After all there are some very good turntables (from Technics as well as other manufacturers) at considerably less than half the cost of the SP10 Mk II. In the end each prospective buyer has to weigh the odds and decide whether cost effectiveness for his purposes is met by this model. As a test bed for my own evaluation work, I have no hesitation in choosing this new turntable without reservation.
Reviewed by John Borwick