Fun with vinyl measurements

[JP]

OMG!
Calibrating the pickup would last longer than the record playing time...

For THAT record.

 

[morillon]

Even when they are made with great care and at great expense, the results are troubling. This video of a boutique fabricator at work is horrifying to me. Look at how they bend, peel, and center the records by eye. Certainly vinyl shows how much you can f-up a recording and still get a pleasurable result. And that's only because human hearing is pretty limited--not to mention that most enthusiasts are aged--and people don't usually listen to it on good headphones! Poor listening room conditions help too.

indeed.. as we all listen more with our brain than our ears... invite you to make small signs indicating, on the front of your devices, their sinad at 1k and snr ... (see backlit for if in the dark etc)
if you allow yourself to appreciate, take pleasure in listening to music, something so personal, etc.,
I can only support you!!
;-)

 

[atmasphere]

could it be a cutter heard resonance or something else?

The cutter typically has a 30dB feedback loop around it so this is highly unlikely.

 

[Balle Clorin]

Time for some classic turntables speed performance ..
Data only valid for the specific turntable, other specimen may vary

And the effect of optimal set-up and a good belt ,vs a visually very poor belt...( too long, slipping, vibrating) and no tuning of set up

 

[Balle Clorin]

Very god wow&flutter on my Gyro SE, but I do get some drift over longer time, I wonder what is causing it?, The belt is very old and stretched but has by far the lowest W&F. I got the HR powersupply and the speed variations has no correlation with the voltage in my electrical socket. 3 years ago I changed the bearing oil and used Mobile 1.
But the process of changing the oil last time screwed up the W&F until I just recently got it back to low numbers.

Any advice or comments?( No I am not getting a Technics)

 

[JP]

Without some form of feedback and a reference I don't think there's any way to resolve that.

 

[Balle Clorin]

Was afraid so, I need an Orbe then to get the speed/motor feedback

 

[atmasphere]

Very god wow&flutter on my Gyro SE, but I do get some drift over longer time, I wonder what is causing it?

If a synchronous motor, its locked to the line frequency which does vary although slowly. If servo controlled it too can vary. The belt stretches and releases as with torque requirements and correction. As the belt degrades, you can get buildup on the motor spindle and in the bearings of the motor shaft.

If you really want spot on speed, direct drive really is the only way to go.

Have you tried a Sutherland Timeline? You put it on the 'table and it projects dots on the wall. If they drift, its off speed. A Technics SP10 MkIII can keep the dots in the same place all day long while playing LPs with multiple needle drops. So can the SL1200G.

 

[Deleted member 5641]

I have a LP12 that ive upgraded and serviced myself over the years.

Ive been thinking about testing various upgrades and changes and reporting the results.

First up might be a Karousel bearing.

What would be the most relevant measurements to show if Linn's latest pixie dust is doing anything or not?

 

[dlaloum]

If a synchronous motor, its locked to the line frequency which does vary although slowly. If servo controlled it too can vary. The belt stretches and releases as with torque requirements and correction. As the belt degrades, you can get buildup on the motor spindle and in the bearings of the motor shaft.

If you really want spot on speed, direct drive really is the only way to go.

Have you tried a Sutherland Timeline? You put it on the 'table and it projects dots on the wall. If they drift, its off speed. A Technics SP10 MkIII can keep the dots in the same place all day long while playing LPs with multiple needle drops. So can the SL1200G.

There may also be temperature related variation, as belt material may change marginally over time as the temperature of the room varies...

 

[Balle Clorin]

If a synchronous motor, its locked to the line frequency which does vary although slowly. If servo controlled it too can vary. The belt stretches and releases as with torque requirements and correction. As the belt degrades, you can get buildup on the motor spindle and in the bearings of the motor shaft.

If you really want spot on speed, direct drive really is the only way to go.

Have you tried a Sutherland Timeline? You put it on the 'table and it projects dots on the wall. If they drift, its off speed. A Technics SP10 MkIII can keep the dots in the same place all day long while playing LPs with multiple needle drops. So can the SL1200G.

Well over the last week my DC belt driven Gyro has varied day by day by 0.02 rpm or 0.06%. But once in a while it jumps 0.5% from one day to another. I then adjust the speed by the DC PSU. But i also do get short deviations like shown in my plot . I use ShaknSpin a great tool.

I guess I have to live with it , no space for a 1200 beside my Gyro and the Gyro stays for emotional reasons, and it is not so bad after all.

 

[morillon]

why not systematize in your exchanges the recent and "hard" 2sigma aes standard?
(even if the figures are less rewarding, the standard seems to be "relevant")

 

[JP]

Well over the last week my DC belt driven Gyro has varied day by day by 0.02 rpm or 0.06%. But once in a while it jumps 0.5% from one day to another. I then adjust the speed by the DC PSU. But i also do get short deviations like shown in my plot . I use ShaknSpin a great tool.

I guess I have to live with it , no space for a 1200 beside my Gyro and the Gyro stays for emotional reasons, and it is not so bad after all.
View attachment 263766

Be careful the chasing of one's tail:

This a set I did awhile ago comparing torque settings on an SP-10R, due to a measurement that didn't make sense but couldn't possibly be wrong 'because a magazine said so'.

Of note, these were done in my basement with a 200lb maple top table with heavy duty industrial legs. The table is in the corner of the foundation, so three legs rest on foundation footers and only one on the slab. Obvious things like turning off the heating system were done to prevent as much vibration as possible. Every step was sequenced and timed to be as consistent as I reasonably could. I threw out one entire set and red-did them because the UPS truck drove by. Of course I indexed the record so the measurement signal was the 'same' each time.

Here are two sets of W&F measurements that were repeated five times in a row. Granted these have a lot more variability having been done with a cartridge and arm.

 

[Balle Clorin]

why not systematize in your exchanges the recent and "hard" 2sigma aes standard?
(even if the figures are less rewarding, the standard seems to be "relevant")

I am not sure I understand What you say here , but I personally find the 2S value most revealing.The only problem is that the noise in Shakenspin data is quite high , that is why I use a 10hz filter In my plot, post #345. DIN and WRMS are to flattering.. They suppress low frequency wow too much I think.

 

[Balle Clorin]

Be careful the chasing of one's tail:

This a set I did awhile ago comparing torque settings on an SP-10R, due to a measurement that didn't make sense but couldn't possibly be wrong 'because a magazine said so'.

Of note, these were done in my basement with a 200lb maple top table with heavy duty industrial legs. The table is in the corner of the foundation, so three legs rest on foundation footers and only one on the slab. Obvious things like turning off the heating system were done to prevent as much vibration as possible. Every step was sequenced and timed to be as consistent as I reasonably could. I threw out one entire set and red-did them because the UPS truck drove by. Of course I indexed the record so the measurement signal was the 'same' each time.

Here are two sets of W&F measurements that were repeated five times in a row. Granted these have a lot more variability having been done with a cartridge and arm.

View attachment 263814

You are maybe down to the test record quality limit here I think, A Shaknspin test on a SP-10R would be very interesting

 

[JP]

You are maybe down to the test record quality limit here I think, A Shaknspin test on a SP-10R would be very interesting

The point is the repeatability, or lack thereof. Shaknpsin is nice, but I'm pretty sure you're still listening to records with a cartridge attached to an arm, so the realities of the variability stand.

 

[morillon]

I am not sure I understand What you say here , but I personally find the 2S value most revealing.The only problem is that the noise in Shakenspin data is quite high , that is why I use a 10hz filter In my plot, post #345. DIN and WRMS are to flattering.. They suppress low frequency wow too much I think.

I am much too stuck by the language to participate in your discussions etc.
but where I also find that the use of 2sigma is more interesting...

 

[atmasphere]

There may also be temperature related variation, as belt material may change marginally over time as the temperature of the room varies...

Temperature is more likely to affect the motor if is lubrication isn't up to snuff. Unless the belt is degraded, the temperature has to vary quite a lot to affect it. If the belt has stretched, the motor can't transfer its torque properly. If the belt is too thick, in some cases the platter will run too fast (this is a classic problem with the old Empire turntables, if you get the commonly offered belt from Russell Industries, which is the same belt that was made by Projector Recorder Belt Company, who Russell Ind. bought out; they never fixed that bug).

 

[USER]

I have a LP12 that ive upgraded and serviced myself over the years.

Ive been thinking about testing various upgrades and changes and reporting the results.

First up might be a Karousel bearing.

What would be the most relevant measurements to show if Linn's latest pixie dust is doing anything or not?

I don't mean to offend, but why on earth would someone spend $1200 on a bearing "upgrade" for an old turntable? If the difference between a turntable with a functional bearing and your old one is audible, then the problem was with your old turntable and bearing, in which case you are better off either fixing it or even replacing it with a cheap modern turntable.

You are likely not getting feedback because most of these "upgrades" are snake oil for people with disposable income and there is little interest for that here.

At any rate, I am not here to offend and I am trying to be helpful. You'd likely get the best information by measuring wow and flutter. Easier said than done, however, as you need to find a good test record, which is extremely difficult these days. Looking at a recording of the test track and running it through the script on this site could show you if there are issues with the bearing you currently have or if it needs cleaning or re-adjustment. Even if you measure the "updated" bearing, it really won't provide useful data for the rest of us as it is likely to only tell us that it is a functioning belt-drive turntable.

Edit: if you are still up for it and finding a good test record, make sure you have a good understanding of how your current turntable is working before you change anything. If you are able to make a recording of the WF test track, I or any number of members can help you with processing it through the script so you end up with something like this, likely a best case scenario:

This is a Clearaudio Concept turntable I used to own. The results are quite good for a belt drive. (As no test record is without issues, some of them must be on display. Here it is slightly off-center.) I find that the weaving in and out (wow) is pretty normal for belt-drive turntables. When this (measurement) is compared with the best direct drive turntables of the 1980s, this is technically pretty bleh. But I doubt anyone will hear a noticeable difference in sound related to these specs. Drift for this is at around 0.05%. My worst direct drive in need of service is less than 0.02%. (Again, test records have issues so real numbers are likely better.) Perhaps one can hear that difference, but I wouldn't lose sleep over it.

 

[morillon]

if a choice of test disk has to be fixed.. this script will allow you to observe the impact of different fine settings of vtf or vta.. on the curve possibly or in global distortion
(even if in general the approach was rather in frequency or classic imd)