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The Michell Orbe Mk11 with VC power supply.

"Michell Move the Goalposts"

[Italian version]

Product: Orbe Mk11.
Manufacturer: Michell Engineering - UK
Cost: approx 2,100 pounds
Reviewer: Geoff Husband
Reviewed: November, 2001

Introduction

Hopefully anyone reading this will also have been reading and anticipating my series of turntable tests. An integral part of the methodology of these tests is of course the use of a fixed reference for the entire test period of 12 months or more. Getting a high-end turntable delivered here at the rate of one a month has proved an organisational nightmare, but so far it's all gone to plan - except for one thing… The fixed reference is my own Michell Orbe Mk1 with SME IV arm, and I've known for some time that the Orbe was about to undergo a major revision meaning that the 'reference' would be obsolete and unobtainable for others. This is clearly far from ideal and I've been desperately pulling strings to try and get the latest news on the Orbe changes. Months ago I learnt that the change would take the form of a change in motor to DC power and a new matching power supply. The good news was that these were the only changes and would be a 'drop-in' swap for my own Orbe, also John Michell promised to get a kit to me in time for the tests. The bad news was that the kit arrived a month late.

I'm the last to blame Michell as they tried their best and the kit was very 'hot off the press'. The upshot is that the first in the series of turntable tests had to be made using the old Orbe as reference - the alternative would have been yet more delay for the tests and an inevitable 'log-jam' of expensive turntables cluttering the family home…

So in the end the Recovery test was completed with the old Orbe, but the following 'mini-test' will update the Orbe's rating relative to the Mk 1 and therefore also to the Recovery which was still available for a swift 'back to back' session… All future turntable reviews will be referenced to the full, current, DC powered Orbe.

- as if the tests weren't complicated enough already….

So why a change of motor and power supply in the first place?

Generally top turntable manufacturers don't bring out major changes every year, the reasons are simple, small sized companies (relative to 'Sony'), high investment in tooling and a conservative buying public who are less prone to the 'this years is best' syndrome. So when changes are made they tend to be either significant upgrades or enforced by circumstances beyond the manufacturers control.

In the case of the Orbe it was the latter case, the PapsT motor used for years by Michell in the Gyro and then Orbe suddenly stopped production. This left Michell (and incidentally several other manufacturers) in a fix. The motor and it's custom power supply the QC, is an integral part of the Orbe's performance, changing it for something as good or preferably better was a nightmare task.

Michell went through many motors - it took many months - before finally settling on a completely different DC motor. This of course presented another problem. The old PapsT was an AC synchronous motor whose speed was governed by either mains frequency, or a sinewave generated by a special power supply (the QC) to mimic and improve on the mains. A DC motor runs without such a sine wave and the speed is controlled by the voltage the power supply puts out - a toy electric train runs with such a motor and to make it go faster you simply give it more volts…

The advantage of a DC motor is that if it's really good it should lack the stepping or 'cogging' effect of an AC unit and thus run more smoothly and quieter.

These advantages have been known about for a long time and several manufacturers have used DC motors in their turntables including Oracle and Pink Triangle. But perhaps the majority of manufacturers have stuck with AC motors because of the problems of speed accuracy associated with DC motors.

Here's the problem. With an AC motor the motor is powered by the 'pulses' of AC electricity first one way then another at the mains frequency of 50 hz. If the motor begins to run slow the AC frequency drags it up to speed, if too fast the mains drags it back - simple - you can run an AC sychronous motor using just a capacitor to give phase shift, one reason why they're popular at the cheap end of the market.

A DC motor on the other hand runs at a speed dictated by the voltage applied to it, therefore to make it go faster it needs more volts, slower - fewer volts. If life were simple you'd just calculate the voltage needed for 33.33 rpm and leave it at that. However the drag on a stylus isn't constant, increasing with loud passages of music, and what if at the start of the playing period the oil in the mainbearing is thicker than 1/2 an hour later, or on a hot day everything runs just that bit easier than a cold day? In fact the demands on the motor are changing constantly and so given a fixed voltage the platter would speed up and slow down either at random or in time with the music, rather like adding a carriage to the aforementioned electric train slows it down, or driving a car up and down hill with the same throttle opening - disaster…

So any DC turntable works best with a power supply which senses changes in speed and reacts instantly to alter the voltage sent to the motor. This 'feedback' is the make or break for any top DC supply.

So in the end Michell chose a new and powerful DC motor and coupled it with a power supply they claim to be the best there is - we'll see

The results…

Swapping the QC powered MK1 for the VC powered MK11 took about 2 minutes. Just unplug and lift out the old motor, replace with the new in its identical housing and plug in - voila!

The switch is in a slightly different place to the old QC but otherwise it's identical in appearance so I'll not waste download time with a pic…

The old AC Orbe was always a quick starter but the DC motor zapped the platter up to full speed in about 1 1/2 seconds. Considering the weight of the platter this is no mean feat and a finger pressed on the motor spindle showed it to be pretty powerful. Of course the quick start is partly due to the power supply sensing the platter is running underspeed and giving it full throttle from the outset.

Running a test tone of 3000hz showed that pitch stability was much improved. There remained only the slightest almost imperceptible wow - very, very close to the Recovery's speed stability. This boded well, as did the quieter motor and a lack of vibration from same.

And the sound? This was uncanny… I'd described the Recovery as a 'super Orbe' - very similar, but with a tighter more tuneful bass and a lack of bloom which the Orbe possessed. This also freed up a better soundstage. And now? Against the VC Orbe? Before - I could have spotted each turntable blind and every visitor to the house preferred the Recovery. Now if I was being honest I'd have to say I couldn't split them. Even in a switched A/B any perceived differences were easy to put down to the cartridge in use. With the exception of the Music Maker, which clearly preferred the RB900 over the SME IV, any differences could be reversed by swapping cartridges. If you want the usual description of different musical pieces just hop to the Recovery review - I'm not going to write it out all over again… If really, really pushed I'd say that the Recovery still had the tiniest advantage in timing and that with the Orbe there was a hint of warmth remaining that now was a characteristic rather than a fault. But if tomorrow I sneakily swapped an Orbe for someone's Recovery I bet they couldn't spot the difference blind…

And boy am I happy! I'd not been looking forward to the Recovery's removal but now I'm happy to go back to my updated Orbe - Phew.

Scoring relative to 'old' Orbe Mk1 with AC motor and QC supply.

Conclusions.

The change from AC to DC power may have been forced on Michell, but the result for us vinyl addicts is wholly positive. The change adds £100 to the cost of the 'new' Orbe but the improvement is easily worth the extra. More difficult is the price of the upgrade for existing Orbe owners. Here the cost is over £700. The old AC Orbe is a fine performer and needs a turntable of the Recovery's ability to emphasise its shortcomings, but the new motor/power supply lifts the Orbe to a higher plane and in a suitably revealing system the result is clearly audible.

A thought… As the old QC + AC motor use near identical motor/power supply housings I wonder if Michell might be persuaded to offer an upgrade service where they re-use the old casings and offer it as a special deal?

Lastly - many thanks go to Michell for their patience and understanding in helping a nagging writer…

Note… Because of this review and its effect on the future turntable reviews, the review of the Loth-x Aida has had to be put back two weeks and will appear in the 'pre-Christmas' edition.

Thanks

After reading this test I hope it is evident that without the following companies this series of reviews would have been impossible - thanks from me to them:-)

Michell engineeringhttp://www.Michell-Engineering.co.uk

'The Cartridge Man' - http://www.thecartridgeman.com

Graham Slee - http://www.gspaudio.co.uk/

ClearAudio - http://www.clearlight-audio.de

AudioNote UK - http://www.audionote.co.uk

Dynavector Japan - http://www.dynavector.co.jp

© Copyright 2001 Geoff Husband - http://www.tnt-audio.com

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