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variance of +/- 10 Hz with 1 kHz test tone

I tried the Dr. Feickert Speed Tests iPhone app. I don't have his test record for the 3150 Hz track and the app says that you can use a 1000 Hz tone. I have a 1000 Hz tone from the Clearaudio sweep / burn-in record and tried that with the iPhone app running and showing microphone input on the meter. The app registered nothing. Has anyone else been able to get his iPhone app to work with a 1000 Hz tone? Are there any known problems with this app on iOS 7?

I used another iPhone app "Tuner Lite" and it showed my table to average right on for a F# 5 with the tuner set to concert A 440 Hz using the 1000 Hz tone. The Tuner Lite meter did fluctuate between the sharp and flat side (again within the two inner arrows, about +/- 10 Hz and were equidistant on both the flat and sharp side) during even time slices / cycles. Is this wow? Flutter? Good, bad or indifferent? Hole off center on test record? Strobe 33.3 reading looks to be dead on using the same Clearaudio disk with stylus on the record.

Phono setup is:
RP6 with GT ref subplatter and TTPSU
Herbie Mat Way Excellent II-2mm
Audio-Technica AT-33PTG/II 0.3mV MC
Salience / Jasmine LP2.0 mkII

Thanks,

Scott
sbrownnw
sirlordcomic
21 posts
 
"The WOW measurement according to DIN IEC 386 is quite accurate in measuring relatively slow speed fluctuations in a range of <10Hz (WOW). Faster variations (flutter) are a problem to measure with a phone because audio can be sampled at a maximum rate of 44.1kHz which is limiting the measurement of fast fluctuations. Please put the device on a solid base for measurement in order to avoid shaking it which causes some minimal doppler effects and decreases the accuracy."
dinster
76 posts
 
To set your mind at ease look at this thread in which various TT's were tested with the platter speed app, The best was the Nakamichi, which centres the record, most of the big variation is eccentric spindle hole.
http://www.stereo.net.au/forums/index.php?/topic/49224-turntable-speed/page-2?hl=%2Bplatter+%2Bspeed#entry941503
sbrownnw OP
693 posts
 
Tried a red belt from North Hill Audio (from ebay, cheaper than white belt, not affiliated). Good numbers initially:

mean freq: 1000.2 Hz

filtered freq:
-0.04% / +0.05%
-0.4 Hz / +0.5 Hz

Also tested my black belt which has posted the best numbers so far:

1002.9 Hz
-0.09% / +0.02%
-0.9 Hz / +0.2 Hz

It is a lot warmer today (by 20+ deg F) since I last ran these tests. Maybe the black belt stretched? Maybe it is more sensitive to temp? Will listen some to the red belt and re-test again. Both seem to be doing better than the factory white belt I got.

One more test run with the red belt:

1000.0 Hz
-0.05% / +0.04%
-0.5 Hz / +0.4 Hz
sbrownnw OP
693 posts
 
Went back to black belt. Bigger sound stage and more bass.
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