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Does your TT meow?

Maxbertola said:
I'm glad I started an interesting debate, I think that people with high sensitivity to pitch - which may be not the same thing as perfect pitch - are more numerous than is commonly thought. We are trained to judge audio gear by basically a mix of frequency response and phase relationships, but in the case of turntables rotation of the platter is the very thing that creates sound, so perfect rotation is essential to perfect tune.
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Agree entirely. I’ve got good relative pitch, e.g. I can play in key by ear etc, though not ‘perfect pitch’ which is the ability to identify notes by name on hearing and to know if they are slightly flat/sharp vs. an A440 tuning reference they keep in their head. Most people should be able to to identify or at least feel uncomfortable by the sort of wow a turntable can produce with an eccentric pressing, dynamic wow etc, and I suspect the more they are worried by it the more likely they ultimately end up with idler or DD decks, crazy high-mass behemoths etc, or just abandon the whole thing for digital.

My own story is interesting in that I knew damn well I’d lost something swapping my 1st system Lenco L75 for a series of belt drive decks, even though I obviously gained a lot in other areas. I didn’t have the language or knowledge to articulate it at that point, but I knew the Lenco did something the Ariston RD80 just didn’t. There was a rightness that had been replaced with an admittedly far cleaner vagueness. The Xerxes (when it worked) moved forwards from that, but to be honest it wasn’t until this century that I plonked a totally stock Lenco L70 on the floor in front of my Spacedeck that it all came flooding back. The Lenco was hopelessly crude (agricultural tonearm, basic Pickering V15 MM), but it played in tune and in time in an absolutely rock-solid way, and with real enthusiasm and life. I’ve owned a Garrard 301 and my current TD-124 since, and I can’t seem my changing the latter now for anything this side of an EMT 930. I suspect there are direct drive decks out there I’d love too, but I didn’t get on with the SL1200G (just too ‘dead’ to my ears, but I think that is a high mass thing, not a drive thing).
 
The Xerxes IIRC had a sprung mechanism in the motor mount specifically for absorbing motor torque, (i.e. introducing wow ;-). A Garrard motor is suspended by springs too, but they are beefier and I think it delivers energy sooner.

I have a hunch that rigid coupling with the heavy rubber base and the internal power supply contribute deadness to the old SL1200. I took out the power supply and all the base bolts in mine so that it just sits in the base. I don't use a Technics arm. Mine doesn't sound dead, it's detailed, punchy and fun. Quite hard to distinguish from my 301s and Amadeus actually.
 
davidsrsb said:
Regas with bad motor suspension will have noise, not wow
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IME, the most obvious Rega suspended motor related noise that tends to make itself heard is the occasional tapper on startup. Misaligned motors also cause drive belt 'roll' which can occasionally be heard on quiet passages. These symptoms escalate both belt stretch and wear, which, in conjunction with loss of belt tension and grip will have both absolute speed and speed consistency off. The simplest way to avoid/prolong this is by giving the platter a helping hand push on startup, as long recommend by Rega.

When one observes Rega's old suspended motor alignment method, it is interesting to note how tension is applied as a means to set the motor angle just far enough away such that drive belt tension applies final azimuth alignment. This balancing of tension essentially makes the drive belt an extension of the motor 'O' ring suspension by virtue of tension being in equilibrium. Compare this to such as the inexactitude of the old Connoisseur BD1/BD2 motor suspension and the Rega system really did demonstrate elegance of simplicity in its design.

No matter, in this case the OP's mention of his having had a Carbon fitted likely indicates a more recent sticky pad motor mount. Seems there has been an über-accurate, higher Young's modulus EBLT tried, as well.

Here is an interesting read covering the history of Rega's drive belt developments...
 
sonddek said:
A Garrard motor is suspended by springs too, but they are beefier and I think it delivers energy sooner.
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Idlers play by different rules as the drive system speed is just so much faster, the ‘gearing down’ generates so much more torque than the slow motor and loose belt driving a typical belt-drive deck, e.g. the motor in a TD-124 is 1350 rpm IIRC, that is stepped down first by the fast-running belt and step-pulley, then the idler. I don’t know the speed of the Garrard motor off the top of my head, but again it is very fast running and generates a lot of torque due to being stepped-down by the idler.
 
Tony L said:
Idlers play by different rules as the drive system speed is just so much faster, the ‘gearing down’ generates so much more torque than the slow motor and loose belt driving a typical belt-drive deck, e.g. the motor in a TD-124 is 1350 rpm IIRC, that is stepped down first by the fast-running belt and step-pulley, then the idler. I don’t know the speed of the Garrard motor off the top of my head, but again it is very fast running and generates a lot of torque due to being stepped-down by the idler.
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The Garrard is a 4-pole motor, so 50 * (2/4) * 60 = 1500 on 50Hz mains, vs. 60 * (2/4) * 60 = 1800 on 60Hz.

What is interesting to note, and ties in with your observations wrt gearing down via direct 'stiff' paths passing full torque at lower speeds (which is what I think you were aiming at there) is that the average 4-pole belt driven Japan Inc. deck of the 1970s has decent motor torque but has difficulty efficiently passing such on to the platter via the necessary tiny diameter pulley (i.e. lack of 'grip'). Belts must always be somewhat tighter than one might expect with these for good performance; the downside being that they then also pass more motor noise, something that is typically higher with less poles to begin with. That the platters were often little more than cast alloy pie tins didn't help with speed stability much either. It is no wonder that the Japanese direct drive decks showed such a clean pair of heels to otherwise quite similar belt drive models from the same vendors. Their belt drives were also incapable of keeping up with the likes of the cheapest European 16-pole BD models on both noise and efficiency of torque transfer grounds (such as any of the entry level Thorens BD models, or indeed the Goldring Lenco GL85 and later 16-pole Duals, for examples).
 
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Craig B said:
I These symptoms escalate both belt stretch and wear, which, in conjunction with loss of belt tension and grip will have both absolute speed and speed consistency off. The simplest way to avoid/prolong this is by giving the platter a helping hand push on startup, as long recommend by Rega.
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I've never known of this recommendation. I'll follow the suggestion.
An update: earlier today I remembered that I have a 220V to 220V transformer, boxed and wired and ready to be used. I connected it to the mains and plugged the P2 into it. I am not sure about what it does exactly, but be it self delusion or reality, the rega seemed more steady in tune than usual.
 
Maxbertola said:
I've never known of this recommendation. I'll follow the suggestion.
An update: earlier today I remembered that I have a 220V to 220V transformer, boxed and wired and ready to be used. I connected it to the mains and plugged the P2 into it. I am not sure about what it does exactly, but be it self delusion or reality, the rega seemed more steady in tune than usual.
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Now that I think of it, it was the Rega sales rep who long ago suggested to me to give the platter a push whilst switching on. I've always done so and my belts have lasted a very long time.

Rega's 'Hints and Tips using your Turntable' (found round back of the old Planar instructions) included the following...

"Leave the turntable running during a record playing session. Switch on before the session and only switch off after you have finished."​

Interesting use of the isolation transformer, btw.
 
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Maxbertola said:
I've never known of this recommendation. I'll follow the suggestion.
An update: earlier today I remembered that I have a 220V to 220V transformer, boxed and wired and ready to be used. I connected it to the mains and plugged the P2 into it. I am not sure about what it does exactly, but be it self delusion or reality, the rega seemed more steady in tune than usual.
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Fascinating.

You may want to try an AC/AC generator. Audiophile ones are from VPI and PS Audio, likely many commercial ones.

The idea is to convert AC to DC and make synthetic AC at a precise 50 or 60 Hz frequency.

Keep in mind that your power company is required to have stable AC as measured on a 24 hour time.

I have Exactpower subcycle waveform correcting power conditioners - on a cheap digital oscilloscope, the incoming waveform had obvious deficiency in shape re. the output - so it's not a good assumption that your wall AC is supplying a good sine wave to your TT.
 
Direct drive is the only way to get rid of wow. A good belt drive with a heavy platter gets pretty close but never quite really there.
B&O's electromagnetic, tacho-regulated rim-drive was another way to go.

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@davidsrsb - thanks for posting that. I have no idea whether it will add uncertainty to uncertainty, but it's always a good thing to know that your mains are dirty and fluctuating before spending money on sophisticated gear. I always think that it's like discussing posh food recipes having polluted water to begin with..
 
The report is from 2005, the increase in green energy has made the generating authorities relax the tolerance regulations since then, so today its almost certainly worse.
 
A quick update: I am beginning to hear vague traces of the same effect with digital files so it's probably my brain..
Another good reason not to spend much on audio.
Cheers.
 
Maxbertola said:
A quick update: I am beginning to hear vague traces of the same effect with digital files so it's probably my brain..
Another good reason not to spend much on audio.
Cheers.
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I will repeat what I suggested previously. Try listening to problem tracks using headphones to make sure it is not room reflections that are the problem.
 
I'm pretty sensitive to pitch (perhaps because I grew up playing a lot of music and transcribing from records as a kid) and FWIW I hear pitchy playing / singing quite often on digital sources, internet radio etc. Jazz singers are the most frequent culprit but I hear it from instrumentalists too. On a turntable (where the first suspicion might be that it's a reproduction issue rather than a tracking (performance) issue) it's of course much more noticable on instruments without vibrato, especially sustained solo piano. It would help things a bit if record presses would put the hole in the middle :D

I think quite a few people don't mind too much about pitch, though: I once attended a classical concert where the soloist's flute was accidentally tuned a semitone sharp relative to the orchestra and (of course) it sounded excruciating. Half of the audience were looking round at each other with a "What the hell?!?" expression. However, the strange thing was that the other half seemed not to notice at all!
 
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