Fun with vinyl measurements

[Balle Clorin]

After adjusting Azimuth to good crosstalk on the Toshiba LF-10009 record also tried different VTF on my AT-OC9MLii 1.25-1.75 recommended range.
Lowest VTF gives best crosstalk on both Toshiba and Ortofon test records, but the Clearaudio TRS-1007 sweep gives best crosstalk at highest VTF..
I guess VTF affects Azimuth in a way that matches test records differently, but what is the geometric relation between VTF and Azimuth? / does higher VTF drive Azimuth clockwose or anti-c.?..I set my Azimuth at the cartridge....

L&R

L vs L 1.3 vs 1,75g, the shift in crosstalk below I have previously seen when cartridge is tilted counterclockwise wrt Azimuth.

Generally it seems crosstalk/separation get better with lower VTF in my case ( average cross talk both channels)

 

[USER]

After adjusting Azimuth to good crosstalk on the Toshiba LF-10009 record also tried different VTF on my AT-OC9MLii 1.25-1.75 recommended range.
Lowest VTF gives best crosstalk on both Toshiba and Ortofon test records, but the Clearaudio TRS-1007 sweep gives best crosstalk at highest VTF..
I guess VTF affects Azimuth in a way that matches test records differently, but what is the geometric relation between VTF and Azimuth? / does higher VTF drive Azimuth clockwose or anti-c.?..I set my Azimuth at the cartridge....

L&R

View attachment 400274
L vs L 1.3 vs 1,75g, the shift in crosstalk below I have previously seen when cartridge is tilted counterclockwise wrt Azimuth.
View attachment 400276

Generally it seems crosstalk/separation get better with lower VTF in my case ( average cross talk both channels)
View attachment 400278

I have seen a similar phenomenon of crosstalk differing with respect to VTF as well. Curious as to what is going on.

See these measurements of the Empire 2000Z. Note that this cartridge is widely acknowledged as not very good at tracking and so the owner pushed beyond the recommended VTF. Could this be related? He used the CA TRS-1007 as well. But here increased VTF made the crosstalk worse.

I'll also add that I have seen that stylus wear can show improved crosstalk results. Very odd. Could this have something to do with the record grooves? CA TRS-1007 is a copy of JVC TRS-1007 afterall.

Introducing the Phono Cartridge Measurement Library

The V15VMR was according to them, either flat to 10kHz with 5dB dive to 20kHz, or a straight downtilt of 5dB from 1kHz to 20kHz. Yes, there may be two different frequency response curves out there for the cartridge with one more downward sloping. But I don't think it is what they say there...

www.audiosciencereview.com

 

[Thomas_A]

Wear can be understandable since stylus to groove contact patch changes. VTF affects generator position so it can also affect crosstalk but in theory only absolute values and not L-R. Lowest crosstalk should indicate ideal VTF. But since there is also skating force it might affect LR a bit as well.

 

[Palmer]

Wear can be understandable since stylus to groove contact patch changes. VTF affects generator position so it can also affect crosstalk but in theory only absolute values and not L-R. Lowest crosstalk should indicate ideal VTF. But since there is also skating force it might affect LR a bit as well.

Disc-cutting lathes

Stereo Lab recording lathes record lathes cutting lathes

pspatialaudio.com

Not sure if this was posted here before, but a very concise article in my opinion. Things being in vinyl as they are, it is astonishing to get channel separation to the degree that we see, at all.

 

[Thomas_A]

The post adjustment of azimuth is interesting. Something for Parks audio?

 

[Balle Clorin]

Anti-skate changes does not affect Crosstalk or balance in my case, but lower VTF courses mistracking to occur at 80um instead of 100um . I guess 70um is sufficient? Comments?

 

[Thomas_A]

Anti-skate changes does not affect Crosstalk or balance in my case, but lower VTF courses mistracking to occur at 80um instead of 100um . I guess 70um is sufficient? Comments?

Correct. Skate/antiskate force is just a fraction of the VTF and should affect much less. With respect to tracking ability and crosstalk, it is a trade-off. Hgher tracking force improve tracking ability and reduce distortion, while the same VTF might not be the ideal one for lowest cross-talk. You could opt for one or the other within the recommended VTF range.

 

[Thomas_A]

My latest measurements give -26/-27 dB crosstalk for 1.0 g VTF and -29/-30 dB for 1.5 g VTF. (Shure V15Vx/JICO SAS/B latest stylus) using the Ortofon test track. Still quite much higher than my previous stylus that had lower than -35 dB both channels.

Since the recommended range is 1.0-1.5 g, I will not pass 1.5 g. 1.5 g also gives good tracking up to 90 µm/315 Hz. At 100 µm right channel starts to deviate, and it can be adjusted with more anti-skate. But this will be very much more antiskate needed for an average track. Below 2nd and 3rd harmonic distortion for such high-level tracks at 315 Hz. One can clearly see that the third harmonic "falls apart" at 100 µm, right channel.

50 µm
L: -41.7, -59.3
R: -42.6, -54.9

70 µm
L: -38.7, -54.8 (+4.5 dB vs. 50 µm)
R: -39.5, -50.9 (+4.0 dB vs. 50 µm)

90 µm
L: -37.7, -52.6 (+6.7 dB vs 50 µm)
R: -38.3, -48.6 (+6.3 dB vs. 50 µm)

100 µm
L: -36.6, -49.7 (+9.7 dB vs 50 µm)
R: -34.4, -39.4 (+15.5 dB vs 50 µm)

100 µm waveform

 

[morillon]

Do some of you use the old STR-112 in adjustment or verification ?
any feedback on its use?
thanks
;-)

 

[Balle Clorin]

I have used the VTA IMD method on both STR-111 and 112 , posten here earlier. Kind of hard to Get results , distortion is high., Method described in some old Audio articles, worldradiohistory.Com

Post in thread 'Fun with vinyl measurements'
https://audiosciencereview.com/foru...un-with-vinyl-measurements.20278/post-1555041

 

[morillon]

thanks...
I'll look at this closely and see how Virtins'pro or Multitones handles it
(see discuss it with their designers.... ;-) )
;-)

 

[Thomas_A]

Regarding cartridges - the market is not very big today for low and moderately priced cartridges, and is dominated by a few like AT. To me it seems that there are just a few "accurate" cartridges out there that are available. While the ATs are fine for what they are, they do not show that ruler-flat frequency response, but have a certain house curve. One exception seems to be the Nagaoka line MP-200 and up, which could be made linear after good matching. They come at a price but to me they seem be the top candidates on the MM/MI on the market.

Nagaoka also have the JT-80 Jeweltone BK with boron cantilever and elliptical stylus. I saw some measurements of this one here, which made me thinking that it is a real candidate for neutral response.

https://www.nagaoka.co.jp/media/STEREO_3-21_Nagaoka-Abtaster_englisch.pdf

https://www.nagaoka.co.jp/media/062021audiojt80bk.pdf

Anyone that have any thoughts of this one? I might ask some friends in Japan to buy and send it to me as "gift" since it is way cheaper that way.

 

[JP]

I have one but haven’t measured it yet.

 

[Thomas_A]

I have one but haven’t measured it yet.

I would have guessed! Possible to give the Nagaoka a priority line...

 

[JP]

Ha. Which one?

 

[morillon]

Ha. Which one?

JT-80 Jeweltone BK
and
see also ..your subjective feeling too..that remains the purpose ;-)

 

[Thomas_A]

Ha. Which one?

The JT80 BK?

 

[JP]

The JT80 BK?

Meant which priority list.

your subjective feeling too.

You'll have to go somewhere else for that.

 

[morillon]

Meant which priority list.



You'll have to go somewhere else for that.

It’s a shame..because fundamentally it’s the measurement/subjectivity relationship that is interesting..because otherwise what good are these measurements, right?
;-)

 

[JP]

It’s a shame..because fundamentally it’s the measurement/subjectivity relationship that is interesting..because otherwise what good are these measurements, right?
;-)

Depends on how well you know how to map measurements to your perceptions and preferences.