Any quality loss in amplifying multiple times?

[poetofpiano]

I read on the Audacity forums (at http://wiki.audacityteam.org/wiki/Change_Speed) that there is some quality loss when you adjust the playback speed and then adjust it again, as opposed to hitting the undo button and then adjusting the playback speed just once. Is there also quality loss if you, for example, highlight the entire track and use the amplify effect (thus increasing the volume of the entire track), and then highlight a smaller part of the same track and use the amplify effect again to make that small part louder? I can’t hear any quality loss, but I wanted to make sure.

Thanks so much, these forums rock!

[kozikowski]

Audacity works at 44100 sample rate and if you change speed enough, you could push some of the work beyond audibility and it may not come back. That's why some people insist on recording musical masters at 96000. You can't actually hear that much extreme quality, but it resists damage in post production.

That's kind of problem is not likely to happen to Amplify, however, since Audacity works at 32-bit floating bit depth. In English that means you can change the volume of clips and segments quite a bit including overload without significantly harming the show. That only works internal to Audacity. You can't, for example, overload a microphone or whisper into it before Audacity and expect it to recover.

Koz