Very strange waveforms

Hi I have made some DAT-recordings on a PortaDAT and its very dynamic recordings. I have then recorded these recordings on a MAC DIGI001 system and when the level is very low (about -50 db)the waveform on The Pro Tools looks very strange, there are only waveforms on one side !!! there are only a waveform on the upper side, when the level is low. The waveform looks okay, when there are more sound/ input on the DAT-tape. The low-level recordinsg sounds okay, but not when I made a fade-in or a fade-out, then it sounds bad. Any comments ? Have anybody seen and heard this before ? Regards Johnny

Hi Welcome to the forum I have seen this before doing the exact same thing. At the time I thought it was the original recordings on the Dat (not recorded by me) were out of phase, but now I wonder if that it is not something created in the conversion its self. Maybe somebody who regularly does this will have the answer.

You most likely had something in your signal chain (maybe the DAT machine itself) that caused a DC offset. This is where a constant DC voltage is mixed in somewhere with the audio - which causes the waveforms you're seeing. There is an AudioSuite plugin called, you guessed it, DC Offset Removal. Simply highlight some or all of the effected audio and use that AS plugin, it's as simple as that. Good luck.