Idlers vs Direct Drive vs Belt Drive

[Audiophile Bill]

He is mistaken, the primary concern is speed accuracy and low noise, it is also helpful if the table does not store energy , the GPA paper explains everything.
Keith.

Low noise I agree. I think immunity from external vibration should be added too. Speed stability is important for sure BUT perhaps how this is achieved is key.

 

[Audiophile Bill]

Wow and flutter are caused by speed fluctuations.
Keith.

I agree - we are talking cross purposes. I think stability of speed is critical but absolute speed accuracy less so.

 

[BruceD]

I have never heard 'cogging' on the Monaco, pitch is perfect ,equivalent to digital, I can hear rumble on Garrards though, I couldn't live with that, is it caused by the idler system?
Keith.

At least the musicality of the Shindo Garrard low rumble or not --overrides the incessant "cogging" of the Monaco--I couldn't live with nor recommend that as for your "equivalent to Digital" comment--save me

You like the GP I like the Garrard

Lets beg to differ and move on

BruceD

 

[Halcro]

We will never see vestiges of a decent servo control in a picture of an oscilloscope showing a 3150 Hz tone - IMHO this picture does not add nothing to the debate.

The typical response of 'The Subjectivist'.......
Do not show me evidence which contradicts my view of the world
You will notice that there is no explanation of why this analogue frequency response trace (it is not an oscilloscope) cannot show the effects of...."a constantly adjusting servo-control" nor is there a single shred of scientific evidence to support his statement.
We have become so conditioned to unsupported subjective statements in the audio world, that we allow any claim to go uncontested.
This is understandably the result of decades of measurements for loudspeakers and electronics simply not corresponding to that which we are able to hear....
This non-correlation of science and our subjective experiences have led us to believe that we are able to hear things better than we are able to measure them.
In the case of speed accuracy and constancy of turntables.....this is patently not the case.


Here are two Frequency Response Charts which Michael Fremer produced (via the Feikert Speed App) for the George Warren and Wilson Benesch turntables (both belt-drive) showing serious deviations in absolute speed and consistent speed.
Yet during the listening tests conducted beforehand, Fremer was unable to hear the effects of these deviations.
Now imagine if we had a contributor to these Forums who had had vast personal experiences with all manner of varied turntables and proclaimed that the best one he had heard was the Wilson Benesch...?

And here is a trace of the Frequency Chart of my Raven AC-2 showing that a good belt-drive turntable can produce good speed-test results.

I have no reason to believe that David's great belt-drive and idler turntables won't measure well under test. In fact I suspect that they do.....
But please don't postulate that you can hear the servo-control constantly operating on a well-designed DD when it simply fails to be measurable.

 

[spiritofmusic]

I have to say I heard the GP Monaco at Purite's for a good couple of hours thru his lovely Cessaro Liszts, and I was captivated. No sign of cogging to my ears (I suspect cogging may manifest itself as coldness, but this wasn't my experience listening to the GP). Trans Fi Vic's problems w/early iterations of servo speed feedback were eliminated according to him when moving to high torque set and forget analogue speed control via direct rim drive, and the finished Salvation to my ears is as much a triumph as the Monaco. I personally didn't get on w/the DD Brinkmann Bardo, and yet Fremer prefers it to the Monaco. I would love to hear the Saskia Ref 11 at some stage because this may be the cost no object destination point for idler drive. Not sure if this uses a servo to speed hunt/correct? I've liked the modded Garrard 301's I've listened to, but not the 401 or Lencos.
It may be that drive mechanism is critical, but only once every other parameter like vibration control/arm board resonances are taken care of, eg the Monaco DD appealing to me more than the Bardo DD, in the main because other design decisions on the Bardo are inferior to the Monaco?

 

[BruceD]

I have to say I heard the GP Monaco at Purite's for a good couple of hours thru his lovely Cessaro Liszts, and I was captivated. No sign of cogging to my ears (I suspect cogging may manifest itself as coldness, but this wasn't my experience listening to the GP). Trans Fi Vic's problems w/early iterations of servo speed feedback were eliminated according to him when moving to high torque set and forget analogue speed control via direct rim drive, and the finished Salvation to my ears is as much a triumph as the Monaco. I personally didn't get on w/the DD Brinkmann Bardo, and yet Fremer prefers it to the Monaco. I would love to hear the Saskia Ref 11 at some stage because this may be the cost no object destination point for idler drive. Not sure if this uses a servo to speed hunt/correct? I've liked the modded Garrard 301's I've listened to, but not the 401 or Lencos.
It may be that drive mechanism is critical, but only once every other parameter like vibration control/arm board resonances are taken care of, eg the Monaco DD appealing to me more than the Bardo DD, in the main because other design decisions on the Bardo are inferior to the Monaco?

Indeed I may heave harshly surmised the GP Monaco--it is a fine DD and though even not on my radar--like I stated deserves serious Audition for clients of the DD--I agree it out performs the Bardo easily

My comments could be biased I must admit to penchant for a Total TT system designed by a master craftsman (Ken Shindo RIP) rather than a "new Wave" designer from the Aero Space Industry

However I am perfectly in harmony with both fields of endeavour--and room for both on our Platforms which is preferred is entirely up to the individual.

I've sat at length with the Saskia/Schröder combo and Mosin has a glorious combo there--highly recommended

As an aside--you mentioned the Cessaro's--I had the pleasure to hear the Carmens -they are absolutely sensational --they seem to do all Avante Garde do but in a superior way

-- our Keith picked winner with that brand in my opinion!

BruceD

 

[microstrip]

Wow and flutter are caused by speed fluctuations.
Keith.

Wow and flutter have specific meanings due to their frequency ranges and the standardized way they are measured. The variations most of us are addressing are not shown in the wow and flutter measurements. Using technical terms as a repetitive but meaningless anthem will not bring you anywhere.

 

[microstrip]

The typical response of 'The Subjectivist'.......
Do not show me evidence which contradicts my view of the world
You will notice that there is no explanation of why this analogue frequency response trace (it is not an oscilloscope) cannot show the effects of...."a constantly adjusting servo-control" nor is there a single shred of scientific evidence to support his statement.
We have become so conditioned to unsupported subjective statements in the audio world, that we allow any claim to go uncontested.
This is understandably the result of decades of measurements for loudspeakers and electronics simply not corresponding to that which we are able to hear....
This non-correlation of science and our subjective experiences have led us to believe that we are able to hear things better than we are able to measure them.
In the case of speed accuracy and constancy of turntables.....this is patently not the case.
(...)
Here are two Frequency Response Charts which Michael Fremer produced (via the Feikert Speed App) for the George Warren and Wilson Benesch turntables (both belt-drive) showing serious deviations in absolute speed and consistent speed.
Yet during the listening tests conducted beforehand, Fremer was unable to hear the effects of these deviations.
Now imagine if we had a contributor to these Forums who had had vast personal experiences with all manner of varied turntables and proclaimed that the best one he had heard was the Wilson Benesch...?
View attachment 23118
And here is a trace of the Frequency Chart of my Raven AC-2 showing that a good belt-drive turntable can produce good speed-test results.

I have no reason to believe that David's great belt-drive and idler turntables won't measure well under test. In fact I suspect that they do.....
But please don't postulate that you can hear the servo-control constantly operating on a well-designed DD when it simply fails to be measurable.

The Feikert Speed App is not a standard measurement. As I told, just showing one print of a digitalization of a 3150 Hz and an ultra low pass signal will not prove there are no perceptible motor cogging effects in the turntable.

Can you point me a link to the specifications of the Feikert Speed App? Thanks.

 

[spiritofmusic]

Indeed I may heave harshly surmised the GP Monaco--it is a fine DD and though even not on my radar--like I stated deserves serious Audition for clients of the DD--I agree it out performs the Bardo easily

My comments could be biased I must admit to penchant for a Total TT system designed by a master craftsman (Ken Shindo RIP) rather than a "new Wave" designer from the Aero Space Industry

However I am perfectly in harmony with both fields of endeavour--and room for both on our Platforms which is preferred is entirely up to the individual.

I've sat at length with the Saskia/Schröder combo and Mosin has a glorious combo there--highly recommended

As an aside--you mentioned the Cessaro's--I had the pleasure to hear the Carmens -they are absolutely sensational --they seem to do all Avante Garde do but in a superior way

-- our Keith picked winner with that brand in my opinion!

BruceD

Bruce, can you elaborate a bit further on the Sakia, how it sounds etc? It's the one SOTA tt that seems to have flown most under the radar, mainly due to high price of entry, and minimal Web discussion. I don't believe it's been reviewed anywhere.
Out of all the top SOTA cost no object efforts out there, it's the one that my current rig is closest to, and if Win really has perfected a proprietary take on a wholly original idler and it fully controls and isolates rumble, it's the one I'm most minded on initial impressions to consider trading my Salvation up to.

 

[Halcro]

The Feikert Speed App is not a standard measurement. As I told, just showing one print of a digitalization of a 3150 Hz and an ultra low pass signal will not prove there are no perceptible motor cogging effects in the turntable.

Yes you told but you provided no supporting evidence for this information.
It is up to you to prove there is "perceptible motor clogging effects in the turntable".
So far we see no measured evidence of it and with due respect......your lack of credible technical explanation for your subjective views do not inspire confidence.

 

[Halcro]

Wow and flutter have specific meanings due to their frequency ranges and the standardized way they are measured. The variations most of us are addressing are not shown in the wow and flutter measurements. Using technical terms as a repetitive but meaningless anthem will not bring you anywhere.

Instead of mouthing meaningless platitudes, it would be more helpful if you provided technical or scientific evidence of the terms you say are "not shown in the wow and flutter measurements"

 

[Mosin]

The constancy and accuracy of a turntable’s speed rotation may not be the most important facet of its performance quality, but one would think it should be a sine qua non.
As Peter Moncrief accurately analised a decade ago…..

Why is speed so important? As you know, the primary job of any record player, including
turntable, arm, and cartridge, is to accurately reproduce the waveform of the music as it was
originally recorded onto a vinyl record.
The cartridge does not read the entire music waveform from the record. It can't.
Why not? Because the vinyl record contains only half of the music waveform.
Where then does the other half of the music waveform come from? It comes from the turntable.
That's right. The turntable is fully responsible for actively supplying half of the music waveform,
and the other half comes from the cartridge.
This puts turntables in a whole new light. If a turntable's job is to actively supply half of your
music's waveform, then it had better be doing its job right, otherwise your music will obviously and
dramatically suffer -- to an extent you wouldn't have imagined when you thought that music's entire
waveform came from the cartridge.
In a record player, the vertical amplitude axis of the music waveform comes entirely from the
cartridge. But the horizontal time axis of this music waveform comes entirely from the turntable.
The key point here is that an error in the time axis would produce a distorted error in the correct
shape of the music waveform, We give a great deal of attention
to making sure that cartridges are accurate reproducers, so that they correctly read the side to side
swings of the record groove that furnish the amplitude information about the music waveform, and
thereby do not distort the music waveform themselves. But that's literally only half the story. We
should also devote equal attention to making sure that the turntable accurately furnishes the time
axis half of the music waveform. If we don't, then the final resulting music waveform will be
distorted, as surely as if the cartridge were contributing unwanted distortion by inaccurately reading
the amplitude axis half in its side to side swings.

Those who claim to prefer turntables which sound “right” but measure poorly can hardly lay claim to legitimacy over those who prefer turntables which sound “right” and measure well…?

Peter Moncrief was right. Thanks for posting his comments. It is important, however, to know what you are measuring, and how the designer arrived at what you are measuring.

Scientific evidence is defined by the purpose of servo controller and how it works. Of course not all designs are equal and the intrusion one hears or not is relative to other factors but its there.



You can't have a dc motor without a controller which is basically a servo and its audible with belt drives too. In regards to the AF-1 the controller is extremely well masked but its still there, hence some of Steve's comments from his visit. Granted its easier to detect when you have other players with AC motors around and its not a cogging but more like an emotional barrier between the music and the listener, less "Natural" compared to the others there. No company that I know of is making high quality AC Synchronous motors today, servo is something that we may all have to accept and live with...

david

Also true, but that isn't to say that feedback can't be good, nor is it to say that high quality AC Synchronous motors never have a place in today's high-end audio scene because they do. By the way there is one company that will make them for you, albeit at a dear price.













At first glance it would seem that Halcro and David are on opposite sides of this discussion. Their posts are not necessarily in conflict, however. Moncrief tells us what is important about a turntable, but he doesn't tell us how to get there.

We are left with several questions, the most pressing is whether we want excellent measured speed accuracy or excellent speed consistency. In my earlier post, I put forth a scenario where measured speed accuracy can be misleading due to ever-changing speed consistency. Still, the measured speed was dead on accurate.

Yet another scenario would be a turntable that employs a design that makes good use of inertia, or uses the brute force of a powerful drivetrain in order to get great consistency. In this case the measured speed may drift very slightly over time, or it may even deviate from absolute accuracy in some other way. It doesn't suffer from a dynamic hit, though, and it doesn't make frequent speed corrections. This turntable has more immediacy, is more musical, but may be slightly less detailed and more romantic sounding. This turntable may sound more colored than a well made direct drive one. If it does, it will undoubtedly bring its detractors out of the woodwork, and justifiably so.

The solution is to combine the better features of both designs while discarding the known pitfalls of both.


EDIT: I am aware that good turntables exist from both camps.
By the way...Thank you, BruceD!

 

[ddk]

Peter Moncrief was right. Thanks for posting his comments. It is important, however, to know what you are measuring, and how the designer arrived at what you are measuring.


Also true, but that isn't to say that feedback can't be good, nor is it to say that high quality AC Synchronous motors never have a place in today's high-end audio scene because they do. By the way there is one company that will make them for you, albeit at a dear price.

Actually I'm high up on AC Synchronous motors and I see them as a necessity for true a high end design. I'm simply unaware of anyone making quality ones so we might be stuck with DC motors as a "compromise" for the time being. Its the dc motor and its controller that I find as one of the two factors compromising the the AF-1, I discussed this with the designer and he didn't disagree.

david

 

[Halcro]

Here is a Link to that Peter Moncrief article in full Win
http://www.iar-80.com/page12.html
I think you will find it interesting to say the least....
He goes on to explain in agonising detail, the problems and travails in designing a belt-drive turntable.
For those 'backyard' tinkerers who wish to join the legion of 'naive' belt-drive builders....this may be somewhat sobering...

 

[Mike Lavigne]

Here is a Link to that Peter Moncrief article in full Win
http://www.iar-80.com/page12.html
I think you will find it interesting to say the least....
He goes on to explain in agonising detail, the problems and travails in designing a belt-drive turntable.
For those 'backyard' tinkerers who wish to join the legion of 'naive' belt-drive builders....this may be somewhat sobering...

Peter never did complete that article. I owned a Rockport Sirius III for 8 years. it's one great tt system.

 

[Halcro]

Peter never did complete that article. I owned a Rockport Sirius III for 8 years. it's one great tt system.

I agree with you......and yes, such a shame Peter never finished the article. He regrets it himself, but I think the first part exhausted him...?

 

[Mosin]

Actually I'm high up on AC Synchronous motors and I see them as a necessity for true a high end design. I'm simply unaware of anyone making quality ones so we might be stuck with DC motors as a "compromise" for the time being. Its the dc motor and its controller that I find as one of the two factors compromising the the AF-1, I discussed this with the designer and he didn't disagree.

david

I lean that way, too. Fortunately, I've been able to obtain high quality AC Synchronous motors for the Saskia turntable.

Here is a Link to that Peter Moncrief article in full Win
http://www.iar-80.com/page12.html
I think you will find it interesting to say the least....
He goes on to explain in agonising detail, the problems and travails in designing a belt-drive turntable.
For those 'backyard' tinkerers who wish to join the legion of 'naive' belt-drive builders....this may be somewhat sobering...

A lot of people believe that an idler or direct drive turntable is hardest to build, but I believe a belt drive is the hardest to get right because it has the most hurdles to overcome. Building a crummy belt drive is easy, however. We see evidence of that almost everywhere.

For a variety of reasons, I chose to work with idlers. There are many ways to properly skin the proverbial cat, though. That's not to say that certain rules are inescapable for those who really want to get it right. It's hard work where a lot of aspects are deceptively simple. A minor mistake can cause a major hit on performance. I'll go so far in saying that if the designer can't think outside the box, he should design something else. I suppose that applies to virtually all of audio, though.

 

[BruceD]

Bruce, can you elaborate a bit further on the Sakia, how it sounds etc? It's the one SOTA tt that seems to have flown most under the radar, mainly due to high price of entry, and minimal Web discussion. I don't believe it's been reviewed anywhere.
Out of all the top SOTA cost no object efforts out there, it's the one that my current rig is closest to, and if Win really has perfected a proprietary take on a wholly original idler and it fully controls and isolates rumble, it's the one I'm most minded on initial impressions to consider trading my Salvation up to.

Yoh SP, What can one say--in the jaded world of audio auditions--to experience a light in the gloomy Corridors of show mediocrity --the chance of redemption is taken with both hands--sorry ears!

Such room with sonic bliss was the Saskia /Frank S/ Miyajima MC ( I recall but maybe wrong there) the presentation was full bodied/sensual/involving and allowed the Music to flow virtually like no other demo-- yes it was that good

But naturally must hear for yourself-I appreciate an audition in the UK may be difficult but where there's a will there's a way --as they say--

persevere indeed and you may come to a satisfying conclusion-- you won't regret it

I'm sure Win will chime in and offer some suggestions to alleviate the perils of distance--in your case

Good Luck,

BruceD

 

[ddk]

A lot of people believe that an idler or direct drive turntable is hardest to build, but I believe a belt drive is the hardest to get right because it has the most hurdles to overcome. Building a crummy belt drive is easy, however. We see evidence of that almost everywhere.

Easy to make and easy to sell crummy!
david

 

[bonzo75]

As an aside--you mentioned the Cessaro's--I had the pleasure to hear the Carmens -they are absolutely sensational --they seem to do all Avante Garde do but in a superior way

BruceD

Aren't those the Super Liszts? When you mention Avantgarde, are you referring to Trios with basshorns, and did you compare full symphony orchestra on the two? The reason I ask is the Carmen's woofer seems similar to the Liszt woofer, i.e. not a horn based woofer, but more like an active box.v Is this a 2-way?