There is a lot of unsubstantiated hyperbole (read: bs) in reviews. If you've been in the hobby any length of time, you already know this.
Source of Fremer's "1 arc second" claim?
In the latest TAS April 2025, page 34, Fremer reviews some Technics TT, and repeats his claim that "listeners in blind tests could hear arc second speed shifts". where one revolution ~1.3 million arc seconds. Anybody have any idea where this is coming from?
Basic math will make you wonder whether any listener can hear a difference between chamber a' = 440.00000 Hz and 440.00004 Hz, rounding the 1.3M to an even 1M. When tuning my violins, I can hear 2–3 cent difference, where 800 cents = 1 octave = doubling of frequency. At 2 cents, that is over 1 full Herz difference. Even playing a cord with tones at 1 Hz difference will result in an oscillation at 1 Hz, i.e. peak to peak 1 second. For easy math, assume even a 0.00005 difference, which would lead to an oscillation with frequency of 20,000 seconds = 33 minutes. Good luck hearing that.
"Golden Ears" being able to hear ten times better than a normal human, why not. But 20K better? We are off by several orders of magnitude. Maybe I don't understand that he is talking about, but I consider it complete BS.
Maybe it has to do with consistency (accuracy vs. precision), but then the a different unit needs to be used that includes time in the denominator. But even then the math/physics don't add up.
If anybody can provide any insights, LMK. Thanks!
The alternative is rather unflattering for Mr. Fremer.
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"I can hear 2–3 cent difference" oberoniaonia- I'm with you on ability to hear subtle differences. I play my guitar along with my favorite artist on LP, and find by way of the tuner, recordings are sometimes a couple of cents higher/lower than A440. Maybe that's the inaccuracy of my table,the recording...who knows? Anyway, it's a way to REALLY hear if your turntable is speed steady- play the same chord against the LP to hear accuracy. My setup gets a B+. Maybe an A- on good days.I hear wavering, not pronounced, but not accurate. It's not a $50K+ rig, so my blood pressure isn't redlining.
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@barts I did not catch the alternative for the initials. Too funny! That, however, was not my intention. @fatdaddy2 totally agree. Frequently a kernel of truth is augmented by acres of BS. Just was wondering what the source kernel might have been for 1 arc second. @tablejockey funny anecdote!
Lots of factors, indeed. There is a general trend of pitch creep, with contemporary players going for a' = 444 Hz. @lewm 1 rpm = 3% = 4 cents which anything other than a manual gramophone can beat by a wide margin. |
The 1-arc-second likely originates from this turntable vendor whitepaper - Oswalds Mill Audio - K3 Whitepaper | OMA of which MF owns (or owned). There are a number of errors in the white paper: "...our device needs to actually physically trace modulations in a vinyl groove to the order of .005 microns." The inherent surface roughness of the record reported by a couple sources is 0.01 to 0.005-microns (100 to 50 angstroms). The RIAA curve is specifically intended to avoid the noise inherent to the record's inherent surface roughness, so the realistic smallest modulation is 0.1-microns, at least 10X the surface roughness. And just to put the record's surface roughness into perspective, its surface finish (inherent to the material and pressing process) is finer than mirror polished stainless steel. As far as the arc-sec, read Minute and second of arc - Wikipedia, it's an angle measurement. To apply that to a record of 12" diameter spinning at 33.333-rpm with outside groove tangential velocity of 51-cm/sec and inside groove velocity of as low as 20-cm/sec. Converting 51-cm/s to radians/sec Angular Velocity Calculator = 3.3456 rads/sec which Angular Velocity Conversion Calculator - Radians, Degrees, Revolutions, and Grads = 191.74 deg/sec Degrees to Seconds Converter = 687,600 arc-secs. Like the OP, the ability to detect 1-arc-sec is not possible. However, angle encoders appear to have accuracies of 5-arc-sec and better accuracy_of_angle_encoders.pdf where "Angular measurement error (arc seconds) = bearing wander (μm) x 412.5/D" where D=mm. If it's assumed a bearing radial wander of 5-microns and diameter of 13-inch, the angular measurement error in arc-sec is 1.2492. But this does not take into account circuit noise, feedback error, etc. Like the 0.005 micron claim, the white paper claim of 1-arc-sec appears (being diplomatic) to be very 'optimistic'. Otherwise, keep in mind that MF is not a scientist or mathematician. He would help himself if he referenced the information source that is well out of his swim-lane, versus making claims that appear to be attributed to him. |
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