Fun with vinyl measurements

[Balle Clorin]

I think Vinyl people in other forums do not want to know about turntable and cartridge measurements as they may get disappointed.

I like accuracy and good design but that does not prevent me from listening to vinyl or measuring it. Measuring is a way to learn,understand and improve.
Let us share and see various turntable, cartridge and RIAA and related measurements and tips.

Like this analysis of my turntables speed variation, inspired by this
MechanicalResonances0001.PDF (theanalogdept.com)
.

 

[MakeMineVinyl]

I've posted this before, but it seems appropriate here too. This is a comparison of reel to reel tape vs vinyl distortion at their relative reference levels.

 

[Balle Clorin]

Anyone with a smartphone can do a RPM check. While my strobedisk is very stable at correct speed i get +0.24% on the app . The app also show similar w&f variations a recording of A test record.

 

[pma]

Technics SL1200-Mk2 + Ortofon 2m blue. (5cm/s)

And rpm stability is excellent due to crystal oscillator driven direct motor drive.

 

[abdo123]

Anyone with a smartphone can do a RPM check. While my strobedisk is very stable at correct speed i get +0.24% on the app . The app also show similar w&f variations a recording of A test record.

Which app is that??

 

[pma]

This would be the measurement similar to DAC jitter. Technics SL1200-Mk2 again. So please let's not generalize. I get few microseconds deviation after 1 minute.

 

[Balle Clorin]

Which app is that??

Iphone app .
Wow Flutter | Philip Broder
Here it is compared with 31350 Hs test record track, demodulated( converteing 3150Hz signal to speed variation signal) in Audacity by the "wow and Flutter add-in"
Very good match, only snag is that the iphone say the speed is 0.24& too fast when it actually is 33 1/3 but the peak variation is correct

 

[paulraphael]

This would be the measurement similar to DAC jitter. Technics SL1200-Mk2 again. So please let's not generalize. I get few microseconds deviation after 1 minute.

I'd love to see how something like this measures against some of the more e$oteric turntables. My younger vinyl-disciple self might not like the results.

 

[Balle Clorin]

This would be the measurement similar to DAC jitter. Technics SL1200-Mk2 again. So please let's not generalize. I get few microseconds deviation after 1 minute.

View attachment 111900

Nice .
How long period is this over? German audion magizine Stereoplay/audio use 20 sec.(longer period are likely too look worse on belt drive with DC motor due to drift....1 15 minute period doss not look as good at 20 sec on mine


Here is my Michell Gyro SE compared with Technics SL-1500 direct drive over 20 sec. same scale. This day the Gyro gave 0.05% peak variation in Phili Broder app.

correctly scaled

I also measured a Michell Technodec to 0.06% variation the same as I got on a Technics S1200 GR
Both have the same 0.06 % peak variation, bit the Technics is spot on speed. (+0.24%= 33 1/3 on my phone), The Technodec is too fast with the standard PSU, that is why people should get the HR supply for easy speed adjustment.

NOTE!! Phone must be placed on record center. I use a record clamp over the spindle to support the phone in center

 

[Balle Clorin]

Very nice of Rega to share their performance tolerance specs and testing of an RP8.An honest and open company and management.

 

[Judas]

As an Audiophile we have been exploring and trying to cure them throughout the 40 years I have been involved in the hobby. in this forum some one brought Inner grove distortion as though it was recent revelation. The only difference is Audiophiles try to promote vinyl. Often our improvements are empirical rather than measured.

 

[JeffS7444]

View attachment 111949

The Michell turntable seems to have a much lower noise floor: Is that due to it's suspension?

 

[Balle Clorin]

The Michell turntable seems to have a much lower noise floor: Is that due to it's suspension?

Not sure could be the testrecord level, I use Clearaudio Trackablility Test, it has a 15minute 3150Hz speed test track on side 2

 

[pma]

How long period is this over?

OK, the one now attached is over 15s.

 

[LuvTheMusic]

I have no measurements to contribute, but what about the records themselves? Back when I still listened to vinyl, any possible issues with the turntable often were swamped by variations from the record: off center pressings (and they don't have to be way off center), warps (and how many records even start out perfectly flat, much less remain so for years?). Variations from these sources might not be too apparent on some kinds of music, but on recordings of solo piano -- argh!

 

[Balle Clorin]

Most of the test records are poorly centered and not accurate.( I have 10 different) HifiNews test record and DrFeickert are especially bad. Frequency response of white noise and sweeps are questionable.
But phase test and arm/pickup resonance and tracking test are ok.
Some test record require special equalization, like my Bruel&Kjær QR 2009 og 2010. It states W&Flutter track accuracy of down to 0.06% WF

 

[Thomas_A]

Balle Clorin: would be really nice with a good software to analyze such as that you had and showed many years ago. Polar plots an FM/AM demodulation.

 

[Thomas_A]

My player Linn Axis runs a bit slow but have not bothered yet to adjust it. Below is a kHz tone with its distortion components. Tonearm is a Moerch UP-4 and a Shure V15Vx cartridge with a JICO SAS boron stylus. Test record below is Elipson.

Pink noise on the Elipson seems to reach 17-18 kHz. The stylus has a resonance in the 12-13 khz range. Loading is 130 pF and 47 kOhm, if I remember correctly.

The 3150 tone shows 3144,5 Hz, so about 0.17% too slow. Might adjust this some day.

.

 

[Balle Clorin]

Balle Clorin: would be really nice with a good software to analyze such as that you had and showed many years ago. Polar plots an FM/AM demodulation.

How do you make the polar plots?

 

[Balle Clorin]

Speed stability of suspended belt drive with DC motor can be a challenge, but it sound OK and is beautiful.
Now I have 0.1% max speed variation from average, struggling to get down to the 0.05% I had before

YouTube
Friday and an old record on the Gyro - YouTube