Measuring Wow & Flutter of existing 3150Hz recordings

[Steveh100]

I have quite a few recordings of 3150Hz tones from various Turntables and I'd like to identify their W&F.
Also, I have the Virtins test tones so I can check the system works well.
How do I run these recordings when using the preset W&F modes?

Thanks

Steve
Steveh100

Posts: 1
Joined: Wed Mar 31, 2021 11:00 am
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[VirtinsTech]

Method 1 (Analyze the recorded WAV file):
1. Load the recording (assuming it is a WAV file) via [File]>[Open]
2. Right click anywhere within the Spectrum Analyzer window and select [Spectrum Analyzer Processing] and then tick "Wow & Flutter", tick "Unweighted" if necessary. Change the FFT Size (bottom right) from the default 1024 to 32768 or higher if necessary.
3. Click the DDP Viewer button in the second toolbar from the top and select the Wow and Flutter related DDPs (e.g. WowAndFlutter_A(%)) to display.

Method 2 (Real Time Measurement):
1. [Setting]>[Load Panel Setting] and load one of the following Panel Setting Files:
(1) \Pro\WeightedPeakWowAndFlutter_10s.psf.psf
(2) \Pro\UnWeightedPeakWowAndFlutter_10s.psf
(3) \Pro\WeightedPeakWowAndFlutterFrequencyCounter_10s.psf
(4) \Pro\UnWeightedPeakWowAndFlutterFrequencyCounter_10s.psf

2. Start to measure through your ADC device (e.g. sound card)

[Steveh100]

Thanks

Your method 2 (Real Time Measurements) works fine

Method one gives me this as per the attached file

[VirtinsTech]

In the current version, the Wow and Flutter measurement will not be performed if the Record Length in the Oscilloscope exceeds 2097152 samples (about 43.69 seconds if sampling rate is 48kHz). You can use [File]>[Extract] to save a shorter copy of your recording and then use [File]>[Open] to open that copy to analyze.

[Steveh100]

Thanks

You say currently thus implying this will change. Ideally, I like to record 60 ish seconds at 24Bit 96kHz. Not that I need this now but who knows what I might need next year.

One final question: is there an easy way to show average speed either as a percentage above or below 3150Hz or the related rpm ie 33.357?

[VirtinsTech]

Yes, the software will be improved continuously.

User Defined Data Points (UDDP) can be used to display the average speed deviation in percentages and average speed in RPM. Click the DDP button in the second toolbar from the top and select a UDDP from UDDP1(UU) to UDDP16(UU) in the Derived Data Point list, then enter its Alias, UDDP Definition and Unit as follows:

If the average carrier frequency is measured using the Spectrum Analyzer, then:
Alias: Average Speed Deviation in Percentages; Definition: ([f1Freq_A(Hz)]-3150)/3150*100; Unit: %
Alias: Average Speed in RPM; Definition: (([f1Freq_A(Hz)]-3150)/3150+1)*33.33333; Unit: RPM

If the average carrier frequency is measured using the Frequency Counter function of the Multimeter, then:
Alias: Average Speed Deviation in Percentages; Definition: ([Freq_A(Hz)]-3150)/3150*100; Unit: %
Alias: Average Speed in RPM; Definition: (([Freq_A(Hz)]-3150)/3150+1)*33.33333; Unit: RPM

[Steveh100]

Many thanks