🚀 go-pugleaf

I recorded an organ concert and edited (cut) the take into smaller files to take away a few seconds from between the pieces. Then I recombined those 9 files in Audition mixer window using 2 channels to make a 1 second crossfades between the tracks, the idea was to make one aurally continuous file for a CD, steady ambient noise, organ blowers etc, between the tracks.

The original files sound just fine (24/96), as do the cut files and the same downconverted to 16/44 with noise shaped dither.

The WAV file that I exported from the mixer shows a strange fluctuating noise at about -70 dB level which appears only when there is a strong low frequency signal from pedal 16 & 32 foot flue ranks. This appears only on the left channel. It can be seen clearly in the frequencuy analyzer window (noise floor jumps up and down about 20 dB in concert with beat frequences from the pedal), and unfortunatelly it can also be heard on a good system. The modulating frequency is about 2 Hz, noise is broadband, but masked by music from below 8 kHz or so.

I made tests with the original 24/96 piece files by exporting to WAV from mixer, same result. To AIFF, ditto. There is something wrong with the mixer.

The workaround was to make the crossfades in CD Architect, no fluctuating noise from there.

Does andybody have any idea why this happens? And only one channel?