Audacity based Wow & Flutter Visualiser
 

Recent acquisition of a wow & flutter meter has given me the ability to measure average levels, but it is also useful to actually be able to see the unsteadiness. The attached plug-in allows Audacity to display the wow & flutter contained in imported, or recorded audio.

The attached file needs to be unzipped and the resulting *.ny file needs to be copied to your Audacity Plug-Ins directory and, if you're using a recent version, enabled in the 'manage' function.

This done a new item 'Wow and Flutter Visualiser' will appear under the 'Analyze' menu (see picture). Now record a 3kHz or 3.15kHz mono tone from a test disc or tape.

The recording should look like the 'Before' picture (this is a recording of the 3kHz tone from LXT5346). Now click on 'Wow and Flutter Visualiser' and the file will be analysed and look something like the 'After' picture. + and -1 represent +/-1% peak wow and flutter.

The data is presented raw, there is no RMS or weighting so any defects can be clearly seen. This trace is from a modern AT-120LP direct drive turntable and probably represents the limits of my test disc.

Finally the comparison picture shows the results from the AT and some vintage turntables. Top trace is the AT, second down is the Collaro 4T200 (results very similar to the AT, so again probably the limit of the disc). Third down is my Garrard 301 - slightly worse. Finally the Goldring-Lenco GL58 which is a lot worse.

Regards,

Paul