Author: Geoff Husband
Readers of my turntable test series will be aware that over the last few months the inevitable has happened and I've become dissatisfied with my own Orbe/SME4 combination.
The danger of having a load of exotic turntables was always going to be that they might show up faults in my own system and so it proved to be. In my case the problem resided in a rather bloated mid-bass performance compared to the best. It's a criticism I've read concerning the SME in particular, but not so much with the Orbe. So it was starting to look like the turntable test series was going to have a rather expensive conclusion for yours truly.
Of course all these things can be in the mind and are one of the major symptoms of upgraditis, but in my case two test turntables remained (for the moment) and with switched A/B comparison the weakness was laid bare.
My personal view was inclined to blame the Orbe/SME combination rather than either one in isolation - heresy as each was designed with the help of the other and John Michell himself uses an SMEV. Still I thought I could spot a problem, primarily a resonance in the Orbe chassis at the "problem" frequencies - the very rigid mounting of the SME dumping too much energy into the chassis.
This was simply demonstrated, by placing a stylus on a static record, turning the gain to moderate listening levels then tapping either chassis or armboard with a finger or pen. The resultant "gong" noise from the chassis has to be adding colouration, and repeating the test with other tables showed that none had a remotely similar problem - all producing a "thunk, thunk" instead.
So the "loop" of cartridge > arm > armboard > chassis (Where the "boing" happens) > mainbearing > platter> disc> cartridge etc was too much. In my case another possible culprit was the microphony of the Audion power amps, which when tapped 'sung' at a very similar frequency - something not a million miles from feedback, so other owners may not have these problems. However only the Orbe had showed this up, the other six turntables I'd had here didn't seem to have the same problem.
I reasoned that somehow the loop had to be broken and to this end tried the Hadcock 242 unipivot. I guessed that the 'point' contact would dump less energy into the armboard and thus maybe would be cleaner.
Bolting up either the Music Maker or the Dynavector XX2 proved exactly that. The sound cleaned up considerably and in my system (always remember that) the result was a big improvement, the bass became tighter and faster and the midrange, now less 'cloaked' became much more open and airy. In fact the Hadcock 'stuffed' the SME out of sight...
So there I am feeling smug at having found and solved the problem. I was doubly happy because Steve Davey was coming for the weekend for an extended session of vinyl delights and red wine, and I really wanted him to hear and confirm my own findings before I went to press - they were after all rather controversial.
So the great day arrives. I'd set up the Roksan Xerxes/Artemiz (next test - it had just arrived) with the Dynavector XX2 and had put back the SME4 on the Orbe with the DRT-1.
I won't go into the detail of the session as there's a full test to come, but the result was a major upset. Steve, who also owns an Orbe, was all set and primed to have his pride and joy shown up, but when the first back-to-back happened the expected Orbe/SME 'bloom' didn't materialise. In fact Steve was of the firm opinion that the Orbe was the better of the two and I had to agree.
Feeling a bit embarrassed I sort of came to the conclusion that the Roksan has a similar character and so was not showing up the Orbe as much as the other turntables, though it did seem to be sounding unusually good.
OK - now to prove my point I dug out the Audiomeca Romance, a much cheaper turntable than the Orbe, which had plainly showed the Orbe up as being a bit 'fat' sounding. Again the Orbe sounded wonderful, full and organic but NOT 'bloated' and sounding, for the first time, worth the extra money over the Romeo (which I still think spectacular for the money).
By this time Steve is starting to sound polite about my opinions (published by now on the Romance review) and I was starting to get defensive.
"OK-OK, wait till you hear the Hadcock". So a bit of fiddling and the Hadcock was bolted up and spun. It sounded superb, even better than I remembered and we listened for an hour or more just because it was so good, BUT it didn't show up the Orbe/SME in the way it had done before.
So what the hell was going on? Maybe I had been hearing things for all the other tests, but with A/B comparisons that's hard to believe, and in each case there had been others here who spotted the Orbe/SME's Achilles heel. So what was going on? NOTHING else had changed...
And then the penny dropped. One tiny little change I'd made for convenience could, just possibly, be the cause.
You see when I'd swapped the SME back I'd just become fed up of dropping the little black plastic arm-board spacers down the back of the deck every time I'd taken off the armboard. I'd got a little bit of Blu-Tac and made a thin ring of it round the ends of the spacers so that when I removed the armboard the spacers would come too, rather than diving behind the hi-fi. Could this tiny layer of isolation between armboard and chassis be the 'magic' cure that seemed to have transformed the Orbe?
By now Steve had gone back (no doubt baffled by my reviewing) and so I was left to play myself. Removing the Blu-Tac brought back the 'bloom'. It seemed incredible, but in one minute, and at no cost, I had found a solution to the problem that plagued my front end. Here I began to think I was losing the plot but I knew what I heard...
Then, by coincidence a TNT reader emailed to say that he too had a 'bloat' problem with the Orbe and an SMEV, exactly as I described it in the Romeo review.
His mail read
"I've owned both of these for about 4 to 5 years now; to be honest I've never been totally satisfied but have stuck with it anyway. Previously I had a Rega arm on the deck and was quite pleased; I think you are when it costs so little because you don't expect much. When I bought the SME I thought all my worries would be over but no. I've tried upgrading the springs and tone-arm cable, to Nordost Quattra-fil, but still a lack of clarity and too much fatness.
Werner tells me you have experimented with different arms and I would appreciate it if you could relay your findings to me. I will purchasing the new DC motor at the end of the month to see if that can remedy things slightly".
So at the risk of being seen as some kind of nutter I wrote back to ask him to try the Blu-Tac trick and get back to me. The next day his reply came winging back...
"Well thankyou Geoff, huge improvement I must say. Deeper, cleaner, more musically satisfying. As if a load of mush/noise has been removed to allow the music to just appear. Speed, clarity have all been increased but mainly overall neurality from record to record is obvious now."
:-)
So I wasn't hearing things....
I then contacted Len Gregory (AKA 'The Cartridge Man') and asked him to try the same thing with the Orbe he uses to demonstrate the Hadcock.
Next week a phone call to say what an improvement it wrought and in exactly the same areas I'd found. He also said that inspired by it he'd tried putting a 1/2 mm sheet of rubber on top of the mainbearing to separate it from the platter, and that this too had helped. I tried this too and though the result wasn't the big change of the Blu-Tac on the armboard I think it too lifted the Orbe's performance - thanks Len :-)
Then to confirm my 'mad' results I learnt that Michell appeared aware of the problem because the black armboard spacers are made from a vinyl-like plastic rather than the metal previously used - the point is that I think they still don't give anything like enough isolation.
Steve told me that Origin (makers of the Silver 250 arm he owned) had told him to bolt it up 'finger tight' rather than the 'damn tight' you'd expect - they too seemed to be on the case.
Then I discovered that Michell deck modifier extraordinaire Gert Pedersen had just designed a neat armboard damping set which replaced the original spacers, so he too was working on the problem. In fact he's just sent a set for evaluation and I'll be reporting soon (yes it does work!).
So I'm not alone...
OK convinced? This is going to take you 20 minutes and is totally reversible so all you Orbe (or Gyro) owners out there - give it a go. Just unscrew the armboard and remove it along with bolts and spacers. Make up 6 thin (1 mm will do) rings of Blu-Tac and place one on each end of each spacer. Now press the spacer onto the armboard so the Blu-Tac holds it in place. Now just replace the armboard and bolt it up - personally I also allow a tiny bit of Blu-Tac on the threads of the bolts so that if they become loose they won't rattle. Now clamp the thing up tight. Once tight you can back off the bolts a little if you like so that it's the Blu-Tac only that locates the board, but the bolts will still be there for safety.
Then prepare to be impressed :-)
As it now stands my Orbe/SME4/Blu-Tac is absolutely superb, and I now would not consider changing it. If the mod had cost £1000 it would have been good value - at worse it makes armboard changes easier :-)
The only snag is that it lifts the performance of the Orbe so much (in my system etc) that the Orbe is no longer a valid "fixed" reference for the turntable review series, so for that purpose I have to remove the Blu-Tac, but at the end of each test it goes right back on!
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© Copyright 2002 Geoff Husband - http://www.tnt-audio.com