Turntable Speed: What matters?

[PeterA]

I would like to start a thread to discuss the issues of turntable speed and to create a location to post results of speed evaluations . How accurate does turntable speed need to be? How do different drive types address the issues of speed accuracy versus speed consistency. How important are torque and platter mass? What about the motor controller? Is the Sutherland TimeLine the best way to confirm speed or can the KAB strobe disk suffice?

Here is an evolving list of links to video documents on YouTube which use the TimeLine. One shows a Victor T101 DD turntable and two others I just made with an iPhone of my SME 30/12 BD and Denon DD tables. The first two videos show similar speed results but the Victor video also shows how a high torque DD table can maintain speed through the effects of stylus drag. This is quite informative. The SME requires the speed to be adjusted with the stylus playing.

In the interest of sharing information and learning in the process, perhaps we could create a database on this site showing results of various other turntables: Dobbin's "The Beat", Wave Kinetics NVS, TechDas AFO, Technics SP10 MK2 & MK3, Saskia, Rockport, Brinkmann, TW Akustics, etc. We could then discuss how the performances are the results of specific design decisions.

List of videos in database:

Victor T101 http://www.youtube.com/watch?v=YIuwhsNGQ_c

SME 30-12 http://www.youtube.com/watch?v=Clwc_c8sVn0&feature=em-upload_owner#action=share

Denon DP-45F http://www.youtube.com/watch?v=MBEWM7WJ7yo

Technics SP10 MK2a http://www.youtube.com/watch?v=haqhT6khqZY&feature=youtube_gdata_player

 

[mep]

Once you hear a good DD table and what true speed accuracy/stability sounds like, it's hard to go back to belts and suspenders. I love my SP-10 MKII.

 

[jazdoc]

Here is my response to a similar thread on Audiogon (with edits):
http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1354380470&openusid&zzJazdoc&4&5#Jazdoc

"Interesting how the general question regarding drive implementation has quickly narrowed to a focus on speed stability per single revolution. I suspect that this is because this is one of the most easily measured parameters. It is human nature that people respond to what is being measured and audio is no different. However, this can have untoward consequences. I am old enough to remember when THD was touted as the ultimate measure of amplifier quality. However, improvements were achieved with increasing negative feedback; ultimately with deleterious effects on the end product.

Single revolution speed stability is clearly important, but, perhaps, this is not the only (or even most) important consideration. As others have alluded, the Timeline only measures accuracy per revolution, not speed changes within a revolution. Theoretically, if the first half of the revolution was 16 2/3 rpm and the second half of the revolution was 50 rpm, the Timeline would be spot on at 33 1/3 rpm. I doubt that anyone would consider this a quality turntable.

I suspect that the amount of internally generated noise and vibration and ability to dissipate both internally generated and external noise and vibration are also important to the overall quality of any turntable. At a certain level of performance, are other parameters more important to vinyl playback performance, i.e. tonearm and cartridge quality? At what point do vinyl inconsistencies (eccentric spindle holes, warps, etc) overwhelm the advantages to improved turntable speed consistency?

For the record, I'm not a turntable designer and own a belt drive turntable but would be comfortable owning any number of idler wheel and direct drive tables. Additionally, a recent upgrade to my turntables motor controller has really raised the level of performance. At the same time, I've witnessed how different belt materials can alter the sound."

 

[puroagave]

I switched to a laser tach, It gives you a numerical value for precise adjustment and takes stylus drag into account. I think clearaudio has the best close-loop speed control i've seen for belt drives using an optical device to monitor platter speed that talks to the controller in real time.

 

[rockitman]

Once you hear a good DD table and what true speed accuracy/stability sounds like, it's hard to go back to belts and suspenders. I love my SP-10 MKII.

I would put up my AF1 belt drive against any DD table. I'm not aware of any DD that has a built in tachometer that measures speed and adjusts for variations on the fly in real time like the AF1.

 

[Johnny Vinyl]

I switched to a laser tach, It gives you a numerical value for precise adjustment and takes stylus drag into account. I think clearaudio has the best close-loop speed control i've seen for belt drives using an optical device to monitor platter speed that talks to the controller in real time.

OFF-TOPIC

Rob - I just noticed your signature.....nice!
(and no...I'm not the new Bob!)

 

[mep]

I would put up my AF1 belt drive against any DD table. I'm not aware of any DD that has a built in tachometer that measures speed and adjusts for variations on the fly in real time like the AF1.

I'm not looking to start a "my table is better than your table" war here. All I'm saying is that if you compare the speed stability of really good DD tables and compare them against the majority of belt drive tables, I would be surprised if belts come close. Of course I could be wrong and I am often wrong. You have one of the most expensive belt driven tables on the market right now and the speed stability better be real damn good.

I get a kick out of turntables with motors so weak that you actually have to start spinning the platter by hand in order to remind it of what it's supposed to be doing on its own.

 

[Johnny Vinyl]

I'm not looking to start a "my table is better than your table" war here. All I'm saying is that if you compare the speed stability of really good DD tables and compare them against the majority of belt drive tables, I would be surprised if belts come close. Of course I could be wrong and I am often wrong. You have one of the most expensive belt driven tables on the market right now and the speed stability better be real damn good.

I get a kick out of turntables with motors so weak that you actually have to start spinning the platter by hand in order to remind it of what it's supposed to be doing on its own.

I assure you my NA runs as accurate as yours despite the "push".

 

[mep]

I assure you my NA runs as accurate as yours despite the "push".

Oops. You have one of those tables with a weak motor? They remind me of having to push a car so the owner can pop the clutch to get it started. To me, that is a flawed design. To others I'm sure it's a sign of audio nirvana. I would wonder how much stability under load a table with a weak motor has. When you say your speed is really accurate, is that with no record on the platter and you are just measuring the speed of the platter spinning?

I'm not picking on your table John. All that matters is that you love how it sounds. What I think about your table means nothing. I have never heard an NA table and have no idea how they sound. I do know that I have owned lots of belt drive tables over the years with my last one being the VPI TNT with the SDS motor controller.

 

[Johnny Vinyl]

Oops. You have one of those tables with a weak motor? They remind me of having to push a car so the owner can pop the clutch to get it started. To me, that is a flawed design. To others I'm sure it's a sign of audio nirvana. I would wonder how much stability under load a table with a weak motor has. When you say your speed is really accurate, is that with no record on the platter and you are just measuring the speed of the platter spinning?

I'm not picking on your table John. All that matters is that you love how it sounds. What I think about your table means nothing. I have never heard an NA table and have no idea how they sound. I do know that I have owned lots of belt drive tables over the years with my last one being the VPI TNT with the SDS motor controller.

I say thanks for different design, and what one views as a flaw is another man's ingenious discovery. The point is, when well-executed they likely provide equal performance or a satisfactory one for the owner.

On the the subject of speed accuracy I'm not sure if it's absolutely critical to run a TT within exact 1/100th accuracy. I say that as I don't believe every or possibly any TT does that. Mine probably doesn't and I'm not concerned about it. Some will say I should be as even a slight difference of a few 1/100's will make a difference. A difference to what though? Your ears? I seriously doubt it unless you have magic flappers. And unless my ears can hear it I'll forego the importance of adding a speed controller.

During the day I listen to vinyl almost exclusively, but in the middle of the night I turn to my PC rig for music. I have listened to the same album on both and if my TT were off I'd hear it, although not with the minute variances that some seem to feel is important.

BTW...Classic Records' Sarah McLachlan - Surfacing is killer good (accurate too).

 

[astrotoy]

My go to device is the Monarch PT99. It will read to the thousandth place, i.e. 33.333. Because you put a reflective sticker on the TT rim itself, you can measure the speed with every record and the stylus playing on the record. I typically will adjust the speed (I have a VPI HRX with Rim Drive and an SDS) to a few thousandth's of a rotation for every side of every record when I am doing my rips, i.e. 33.338 is fine. The Rim Drive keeps the speed to within a few thousandths. The Monarch is a Pro tool and therefore about the same price as the audiophile equivalent which measures to the tenth's place, 33.3 (about $125-150 for either one). The spec for the PT99 is that it is accurate to .01% or 33.333 +- .003. I find you need to have it braced securely to measure accurately and not just hold it.

Larry

 

[PeterA]

All I'm saying is that if you compare the speed stability of really good DD tables and compare them against the majority of belt drive tables, I would be surprised if belts come close.

It's not my intension to say which drive type is best. It seems to me that different solutions solve different problems and each type has its advocates. I would simply like to learn how each drive type contributes to speed accuracy and to speed consistency, which may be different problems requiring different solutions. Of course, there are other factors that go into a successful turntable designs like isolation, ability to drain resonances, other noise issues, long term reliability, etc. but that is for another thread.

Mep, if you want a really meaningful comparison, don't you think that you should compare "really good DD tables" to really good BD tables, rather than just to the "MAJORITY of belt drive tables" as you suggest? Those would most certainly include all sorts of low cost, mass produced designs. From the very limited sample of the two videos in our database, the BD does come close to the DD, at least in accuracy, perhaps not in consistency. The reasons for that could be quite interesting to discuss.

Would you care to make a video of your Technics SP10 MK2 and add it to the database? The MK3 has speed adjustability, but I'm not sure the MK2 does. It would be interesting to see how it performs in such a test.

 

[puroagave]

perceptions change over time now DD is the new flavor of the month so it seems. there was a time no self respecting high-end dealer displayed a DD 'table in their SOTA room, exceptions being the goldmund reference/studio.

there's a reason belt drives dominated in the presence of DD because the majority of DD 'tables were inferior sounding entry level products. my first 2 'tables were DDs, I still keep a denon dp75 around to play 'new' vinyl before they're cleaned its no sp-10 III but no slouch either. fwiw, i'm not hearing speed variations between the 'technically superior' denon and a VPI TNT with the Walker controller, they maintain speed stability equally (measured in the thousands w/ a monarch laser tach)

 

[audioarcher]

It's not my intension to say which drive type is best. It seems to me that different solutions solve different problems and each type has its advocates. I would simply like to learn how each drive type contributes to speed accuracy and to speed consistency, which may be different problems requiring different solutions. Of course, there are other factors that go into a successful turntable designs like isolation, ability to drain resonances, other noise issues, long term reliability, etc. but that is for another thread.

Mep, if you want a really meaningful comparison, don't you think that you should compare "really good DD tables" to really good BD tables, rather than just to the "MAJORITY of belt drive tables" as you suggest? Those would most certainly include all sorts of low cost, mass produced designs. From the very limited sample of the two videos in our database, the BD does come close to the DD, at least in accuracy, perhaps not in consistency. The reasons for that could be quite interesting to discuss.

Would you care to make a video of your Technics SP10 MK2 and add it to the database? The MK3 has speed adjustability, but I'm not sure the MK2 does. It would be interesting to see how it performs in such a test.

If Mep does not want to try it out, I would be willing to try it out on my SP10 mk2a if Albert is ok with that. I have not shot a video on my camera yet, but I'm sure I could figure it out. Only problem is, if it's off I'm not sure if there is a way to adjust speed on my table.

 

[mep]

It's not my intension to say which drive type is best. It seems to me that different solutions solve different problems and each type has its advocates. I would simply like to learn how each drive type contributes to speed accuracy and to speed consistency, which may be different problems requiring different solutions. Of course, there are other factors that go into a successful turntable designs like isolation, ability to drain resonances, other noise issues, long term reliability, etc. but that is for another thread.

Mep, if you want a really meaningful comparison, don't you think that you should compare "really good DD tables" to really good BD tables, rather than just to the "MAJORITY of belt drive tables" as you suggest? Those would most certainly include all sorts of low cost, mass produced designs. From the very limited sample of the two videos in our database, the BD does come close to the DD, at least in accuracy, perhaps not in consistency. The reasons for that could be quite interesting to discuss.

Would you care to make a video of your Technics SP10 MK2 and add it to the database? The MK3 has speed adjustability, but I'm not sure the MK2 does. It would be interesting to see how it performs in such a test.

Make a video showing what? There is no external speed adjustability with the SP-10 MKII. With regards to you other comment about fair comparisons, I would compare the speed stability under load of the SP-10 MKII to basically any belt drive table regardless of cost.

 

[PeterA]

Make a video showing what? There is no external speed adjustability with the SP-10 MKII. With regards to you other comment about fair comparisons, I would compare the speed stability under load of the SP-10 MKII to basically any belt drive table regardless of cost.

Mep, if you click on and watch the two videos at the start of this thread, the answer to your question should be fairly obvious. Borrow a Sutherland TimeLine, set it up on you table, play a record and make a video with a camera or iPhone showing the laser dash against some reference mark in the background, just like in the two videos. That should give some indication of the speed accuracy of your MK2. Not having external speed adjustability is part of the design of your turntable and should not exclude the SP10MK2 from being able to undertake such a test.

The video of the SME table was analyzed by Tonywinsc on Audiogon on 12/28/13 here:

http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1320876538&&&/Turntable-speed-accuracy-&&st550

and found to be 0.003% too slow or 6/1000th of one rotation out of 173 rotations during the 5 minutes of the video. The laser dash is 13.5" behind the spindle and drifts to the left slightly by about 1/2", roughly the same amount of drift shown in the Victor DD table video. These are just two samples.

You are invited to "compare the speed stability" of your turntable to any belt drive table in a somewhat scientific and objective manner by submitting video documentation of your table to this database. By "under load" I presume you mean while playing an LP. The two videos in the database show that condition.

I have a local friend who has an SP10 MK2a (it's in a Porter Panzerholtz plinth) and I may be able to test it with Albert's TimeLine before I have to send it back to him. If I can do that, I will post the results.

 

[DaveyF]

Have the new DD tables all conquered the dreaded "cogging" that plagued most ( perhaps all) of the previous DD TT's? The "cogging" was something that I remember was clearly audible in all of the Technics TT's that I heard.

 

[microstrip]

Have the new DD tables all conquered the dreaded "cogging" that plagued most ( perhaps all) of the previous DD TT's? The "cogging" was something that I remember was clearly audible in all of the Technics TT's that I heard.

Davey,
Considering your comment I am sure you never listened to a SP10 mk2. I owned one for some time and did not have any "cogging" at all. And many top japanese DD turntables did not have this problem. Few people know that the Goldmund Reference was a DD. As well as the top EMTs such as the 948, that some people consider one of the greatest DD turntables ever built - JTinn knows about it!

 

[puroagave]

Have the new DD tables all conquered the dreaded "cogging" that plagued most ( perhaps all) of the previous DD TT's? The "cogging" was something that I remember was clearly audible in all of the Technics TT's that I heard.

hmm...DD shouldn't cog as they use a servo controlled DC motor. Did your LP12 upgrade come with the new DC motor?

 

[Bruce B]

Davey,
Considering your comment I am sure you never listened to a SP10 mk2. I owned one for some time and did not have any "cogging" at all. And many top japanese DD turntables did not have this problem. Few people know that the Goldmund Reference was a DD. As well as the top EMTs such as the 948, that some people consider one of the greatest DD turntables ever built - JTinn knows about it!

I can't see how the hell people think the EMT 948 is one of the greatest... I lived with one for about a year and didn't care for it. It's now sitting at MikeL's place.