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Fun with vinyl measurements

Meant which priority list.
Ah, ok :) This is obviously a very important question and I would the last one to know the answer.. :)
 
I got another AT33PTG/II as I think my first unit always had some suspension issues, and I believe I damaged it further by poking around more than I should have.

Anyway, I just measured the new one (which doesn't seem to have any of the old one's tracking issues), and I am seeing a much more highly pronounced resonance in the high frequencies. Unit variation, perhaps? This was really unexpected.

AT33PTG2 #2_2.0 g_~40 pF_100 Ω_CA-TRS-1007 #1 - Side B_norm0_1_17.0_11-02-24.png


Old unit for comparison:

Audio-Technica AT33PTG|II_2.1 g_~80 pF_100 Ω_CA-TRS-1007 #1 - Side B_norm0_1_17 Beta.png

OC9XML for comparison:

Audio-Technica OC9XML_2.0 g_~80 pF_100 Ω_CA-TRS-1007 #1 - Side B_norm1_2_17 Beta.png
 
It does not show the strange LEFT channel wiggly pattern that my has. Both yours look better than mine posted here too. I almost lost faith in PTG since I have seen several have strange once per rev bumps in the response on the CA TRS-1007 record, but strangely only that record. I think some PTG specimen has some some issues, you got lucky with this one I think.Even if it may sound more like a OC9 than PTG

Do you have a plot showing channel balance , not normalized to same in both channels
 
I got another AT33PTG/II as I think my first unit always had some suspension issues, and I believe I damaged it further by poking around more than I should have.

Anyway, I just measured the new one (which doesn't seem to have any of the old one's tracking issues), and I am seeing a much more highly pronounced resonance in the high frequencies. Unit variation, perhaps? This was really unexpected.

View attachment 403573

Old unit for comparison:

View attachment 403574
OC9XML for comparison:

View attachment 403575
Most likely unit to unit variation. My tests of four different boron/SAS/B stylii for the Shure V15Vx also shows variation. I wonder what the variation is due to though. No obvious clues to varying mass when viewed through microscope.

Stylus mass? Unlikely.
Cantilever mass? Unlikely.
Differences in amount of glue? Possibly.
Suspension/damping differences? Possibly, but does this affect HF?
 
Have you tried changing VTA when that happens?
Yes, tried Azimuth, VTF, VTA. cannot get rid if it. See post 511 in Library thread
Linking does not work now

Post in thread 'Introducing the Phono Cartridge Measurement Library'
https://audiosciencereview.com/foru...tridge-measurement-library.46108/post-1782532


index.php


I have found a bump on the record , but why is only my PTG affected, no other cartridge gives the frequency oscillations as PTG, I clearly triggers oscillation in sweep response
IMG_5425.jpeg
 
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Thank you for the replies! I will have to take some more measurements. I really did not expect it to have more of a peak than my XML.

I think this is far more variation than I typically see in measurements of the same model cartridge.

I need to verify levels again on my 2i2 before posting non-normalized measurements. Think I may have bumped a knob.
 
I do not trust anything my Focusrite Solo does, totally erratic behavior and results
 
3.gen

I also have problems with input capacitance and output resistance affecting the results

These settings matter too.. Nor sure what would be correct
t
 

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not always, like when trying measuring a SUT or RIaa, did not work well
 
I got another AT33PTG/II as I think my first unit always had some suspension issues, and I believe I damaged it further by poking around more than I should have.

Anyway, I just measured the new one (which doesn't seem to have any of the old one's tracking issues), and I am seeing a much more highly pronounced resonance in the high frequencies. Unit variation, perhaps? This was really unexpected.

View attachment 403573

Old unit for comparison:

View attachment 403574
OC9XML for comparison:

View attachment 403575
Could it be that the suspension of these cartridges is configured differently? A stiffer (compressed) damper gives a flatter frequency response, but a stiffer damper reduces tracking ability. You can test what tracking ability these cartridges have for example at 1.6 grams using the Ortofon TR record.
 
Two identical copies of the same model of phono cartridge that would give the same result of measuring frequency response are like YETI :) :)
 
worn p mount stylus test. audio technica 122ep stylus tested on signet am10 body
WORN-
IMG_8188.jpgIMG_8195.jpg

at122ep worn.png

so that frequency response in the high end looked super odd. i know this thing is worn, but ive never seen a drop off like that before, so i tested a nos 122ep
-NOS
at122ep new.png

this looks like what i expected. a little bigger of a peak, but essentially the same as the stock stylus for this cart which i posted in the library thread. theyre both bonded 3x7 ellipticals so not surprising. out of curiosity, i decided to put a worn at150sa with its shibata stylus on this cart and test it.
-WORN 150SA
IMG_8158.jpgIMG_8166.jpg

150sa worn.png

even though its pretty worn, it doesnt show that nose dive that the worn elliptical does. makes me wonder if theres something else going on with the worn 122ep causing that dramatic drop. also interesting is that even with this level of wear, the shibata sounds way less blown out and distorted at the end of a side than the two nos bonded 3x7 ellipticals. why are we still using those?
 
Could it be that the suspension of these cartridges is configured differently? A stiffer (compressed) damper gives a flatter frequency response, but a stiffer damper reduces tracking ability. You can test what tracking ability these cartridges have for example at 1.6 grams using the Ortofon TR record.
At 2 grams, the old one would usually have distortion in IIRC the right channel around 70-80 μm. The new one tracks perfectly all the way through 100 μm.
 
i recently picked up 3 vm95en styli for 120 bucks and posted some measurements of a couple of them. well, one got sacrificed to the gods of experimentation.
all thats left of the original assembly-
IMG_8242.jpg
i first trimmed away the plastic so i could use this in my p mount audio technica bodies. that sort of worked. it wouldnt seat perfectly in all of the bodies which would lead to funky looking resonance that would show up on the sweep. it seated pretty well in the am10 body which has laminated pole pieces. however, it had a strange multi peak high resonance in that body.
am10 vm95en original carrier.png

after seeing gramofonik's post over at shf where he removed the cantilever assembly from the carrier of a vm95 series stylus, i decided to do some swaps. i had a broken 150ea stylus that came with the body i bought a while back, so i installed the vm95en cantilever in the 150ea stylus grip since it snaps in place perfectly on the p mount bodies and has enough weight so you dont have to make much of an adjustment in tracking force to get the required 2 grams. this is where things get interesting because the amount of compression on the suspension before locking the screw clearly had an impact on the sweeps.

heres the first go around with the am10 body-
am10 vm95en 150ea 1st try.png


wasnt really happy with that dual peak in the high end so i tried it in a solid pole piece at-pm9000 body
pm9000 vm95en 150ea 1st try.png

i wasnt really happy with that droop, so i decided to try and compress the suspension and go back to the laminated am10 body. that was a disaster. in a factory stylus, the bushing never really looks compressed, but for this test, it looked squished.
am10 compressed suspension.png


so l loosened the screw and lightly kept pressure on the cantilever with my finger before tightening and went back to the solid pole piece body. however i decided to try a pm7000 body which measures 500mh vs the 530 of the pm9000.
pm7000 vm95en 100pf.png

finally starting to look usable, but i decided to go back to the pm9000 body.

pm9000 vm95en 100pf.png


at this point, i decided to stay with what i had. over the years, ive read peoples posts where theyre taking all sorts of different at cantilevers and transplanting them into the holders of all sorts of out of production at carts. i cant imagine doing that without some type of test. i wasnt expecting that multi peak in the am10 body and the slightest difference in pressure on the suspension effected the high end response.

this was all probably a dumb waste of time for most people, but i had fun so dont give me a hard time about it!
 

A dozen or so more tests and you will know what fits and what doesn't, and how to do it correctly. Rome wasn't built in a day ;)

1. Note that the needles you bought should work with a pressure of 2 grams, and cartridges with T4P mounting have a recommended pressure of 1.25 grams

2. The compliance is regulated here by a string - a steel wire that is inside, - the pressure is related to the compliance.

3. There is a high-frequency attenuator at the front, it is a very important element!

4. Meters will come in handy, resistance and inductance, capacitance

5. Of course, you always have to measure, this program is great for that

6. Crosstalk came out very well, the tip was set evenly :)



At_1986.jpg



Clipboard_11-22-2024_01.jpg
 
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