SRA, why 92 degrees

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That bit I get as it's easy to visualise the arc of the needle rather than a straight up and down motion. It's just the scale of it (and apparant ignorance of it in 21st century vinyl playback) I have not grasped.

As Josh note an arc or a straight line depends on the cutter (Neumann or Ortofon, as do the azimuth vary as well). Which makes me wonder if the Ortofon test record is cut by an Ortofon cutter....
 
I have to agree with ThomasA...having just recently purchased a AT VM750SH stylus and freaking out that this was some bees knees needle and would be a baby that needed treating differently...

i have leveled my tt, used a Koetsu baby spirit to level my headshell while on record, checked along the whole tone arm cart....

Have set the heaviest specified VTF by manufacturer, and my needle drops sound like CDs....i used hifinews test lp...found that the background noise, clicks and pops (after vacuum/wet cleaning) made the record near useless...i did test my arm resonance at least.

the differences between single digit or subdigit VTA degrees sound like diminishing returns imo...
 
I have to agree with ThomasA...having just recently purchased a AT VM750SH stylus and freaking out that this was some bees knees needle and would be a baby that needed treating differently...

i have leveled my tt, used a Koetsu baby spirit to level my headshell while on record, checked along the whole tone arm cart....

Have set the heaviest specified VTF by manufacturer, and my needle drops sound like CDs....i used hifinews test lp...found that the background noise, clicks and pops (after vacuum/wet cleaning) made the record near useless...i did test my arm resonance at least.

the differences between single digit or subdigit VTA degrees sound like diminishing returns imo...

It would be of interest to know what you found with respect to the resonance test. AT increased their recommended VTFs to a nominal 2.0 g while the static and dynamic compliance appears the same as their old MM carts (AT440MLb had a nominal VTF of 1.4 g).
 
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Imo, a tone arm without VTA adjustment on the fly by now is simply inferior. A record needs to be tuned in like a radio station. No two are alike because of all the variables involved from the cutting stylus on up to the thickness of the record to the warps in it. 92deg. is the ballpark, no more. Same goes for AS.
 
hi ThomasA - my atvm750SH performed really well with all teh hifinews test LP tests - even the +18dB anti skate test which is supposed to be passed only by the best turntables (i find it hard to believe my setup is that good-unless the bulk of hifi decks are pure crap...)


but to answer your question on the resonance test - my arm resonance was at 9hz.
which is what iv'e read the technics arm to be. i previously had an AT120e installed on the table but before i bought a test lp.
 
hi ThomasA - my atvm750SH performed really well with all teh hifinews test LP tests - even the +18dB anti skate test which is supposed to be passed only by the best turntables (i find it hard to believe my setup is that good-unless the bulk of hifi decks are pure crap...)


but to answer your question on the resonance test - my arm resonance was at 9hz.
which is what iv'e read the technics arm to be. i previously had an AT120e installed on the table but before i bought a test lp.

Thanks, 9 Hz would mean that the compliance is around 15, give or take. This is lower than previous AT models of the 150MLX and AT440 and mimics more the AT95E.
 
Imo, a tone arm without VTA adjustment on the fly by now is simply inferior. A record needs to be tuned in like a radio station. No two are alike because of all the variables involved from the cutting stylus on up to the thickness of the record to the warps in it. 92deg. is the ballpark, no more. Same goes for AS.

If you can upload some needles drops from those VTA changes it would be interesting to listen to.
 
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If you can upload some needles drops from those VTA changes it would be interesting to listen to.
I have none. I have not listened to vinyl in 25 years. But I was a freak when it came to accuracy. I tweaked SRA with sheets of paper, AS on the fly. I owned one of the very first Oracle tts. It looked like the Delphi but labeled "Alexandria" on the face plate back in"78. Bought at Comfort and Sound on 12th Ave. in Calgary. Changes in SRA amount to linearity/time alignment which relate to transparency. Exactly the same audible changes take place with AS. Seems counter intuitive but that's my experience as I recall. I could not distinguish sq differences between the two adjustments. Both seemed to improve or deteriorate sq the same way.
 
I have none. I have not listened to vinyl in 25 years. But I was a freak when it came to accuracy. I tweaked SRA with sheets of paper, AS on the fly. I owned one of the very first Oracle tts. It looked like the Delphi but labeled "Alexandria" on the face plate back in"78. Bought at Comfort and Sound on 12th Ave. in Calgary. Changes in SRA amount to linearity/time alignment which relate to transparency. Exactly the same audible changes take place with AS. Seems counter intuitive but that's my experience as I recall. I could not distinguish sq differences between the two adjustments. Both seemed to improve or deteriorate sq the same way.

Well then I does not really help to investigate this further.

I made some measurements of 10 kHz level and IMD with varying VTA/SRA. I found and published very small changes over quite large arm height adjustment, but nothing to be judged as audible. This was at VE a couple years ago. Results were not conclusive though.

SRA_IM_main.jpg


Thread:

Some measurements of SRA (?) on Ortofon OM40- Vinyl Engine
 
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