Ortofon A90 or Air Tight PC-1

@ Downunder,

Sorry to hear that you're dissatisfied with my suggestions to help set up your cartridge. I'm also sorry to hear that you're not willing to read up on the numerous articles that provide advanced insight into SRA optimization for all cartridges (not just the A90). If you are uncomfortable with the information being discussed here, then it might be worth it to inquire to your local Ortofon distributor about hiring a professional with test equipment to do it for you.

For the rest of the interested parties who DO wish to investigate the topic further, I would suggest checking the Analog Corner article from Stereophile Sept 2009 and June 2010 issues. They give some very excellent information on how one can use an inexpensive digital microscope to get a side-shot of the diamond and then to adjust the VTA so that the contact area can be aligned properly. The techniques discussed for SRA aren't rocket science - they can be performed in a matter of minutes once the USB microscope is set up and focused. It's even a possibility that you might find someone at your local audio society who is willing to let you borrow one.

Of course, one may also do this by ear, but as expected it does require tenacity.

Even though Ortofon recommends that you get the SRA to a value that sounds best with the majority of your records, rather than adjusting for each one, I don't see why one couldn't spend some time with a digital microscope and record the corresponding VTA settings for a 160gm pressing versus a 220gm (or the values in between, perhaps).

Since I'm rarely on these forums (as much as I love to chat about cartridges), anyone who has additional questions may contact me directly - ldorio@ortofon.us is my email address.

Louis/Ortofon

I don't see why one couldn't spend some time with a digital microscope and record the corresponding VTA settings for a 160gm pressing versus a 220gm (or the values in between, perhaps).

One could, but (as I posted just above) the SRA for one 160gm record is not the same as for the next 160gm record.

I've recorded optimal arm height settings on over 1,500 records from my collection. Tenacity, as you suggested. ;-)

Weight/thickness is a reliable guide to a starting SRA setting ONLY when comparing on to LP's on the same label, from the same plant, cut around the same time. Weight/thickness have no value for choosing SRA in a vacuum, so just knowing where X degrees of SRA is on a 160gm record is of little value.

@Dougdeacon, agreed, although you'd be pretty close if the record was mastered according to IEC standards.

Ldorio

I never said I had any problems with setting up the A90. I have read Fremers articles and it helped a lot (it seems TAS did not no?)

Out of 4 professional reviews, only Stereophile was overwhelmingly positive, which does not relate to my listening experiences. It would seem that most reviewers don't understand how to set the A90 up correctly.

I was looking for some more generic/systematic Ortofon recommendations on how to align correct SRA for the A90.

enjoy

Dear Ldorio, if one happen to play - from time to time ... - microgroove records manufactured between 1954 and say 1990 (and I guess thats still the huge majority of vinyl out there - AND of interest) then you will encounter so many different (and huge differences indeed) cutting angles in cutting lathes between the early Fairchild to the later Neuman (and between individual samples of the same lathe-type) that the difference in groove-compliant SRA between say a Opus 3 and a Mercury SR90000 (two extremes of the range) results in about 1/2" in heights at the tonearm base of a 9" tonearm.
Back in the old days of the Mercury/RCA-collectors circle ( Sid Marks, Bob Corsetti, David Nemzer, Carol Keasler and a few others - including myself as a late member in 1988) in the later 1980ies, that was common knowledge among analog audiophiles and the VTA was precisely fine-tuned for the setting for each of the labels of interest (DECCA SXL, EMI ASD, RCA LSC etc.).
Back then none of us would have talked about VTA in any other context but groove (label....)-compliant.
Correct SRA and VTA is a direct function of the cutting angle of the record-groove in conjunction with the polished area of the stylus.
And the engineers at Ortofon-laboratories will confirm that.
IEC standards? You visit the remaining record plants and will still find many different cutting angles around.
Ever wondered why the ET2 or the early Wheaton Triplanar back in the late 1980ies/early 1990ies were that popular among serious record collectors going for the ultimate in sound (we have to include - now that's a surprise ! - the FR-64s w/B60 vta-on-the-fly base here for addressing this issue as early as 1979) ?
Because they featured easy change of VTA and precise return to earlier and different VTA settings.