Adding dither screwed up my exported track!!

[Sinergy]

Recently finished a track, and I have a friend who I was going to have master it for me.

He requested that I export from ableton with the following settings; 16bit, and POW-r2 dither.

I did this, and listened to the exported track, everything sounded alright except for the growl bass in the drop sounded AWFUL, this screeching metallic fuzziness replaced what was a wet sounding vowel bass.

I bounced the growl in the project to audio, this still did not fix the problem.

I then changed the dither back to 'no dither' and the problem disappeared.

I asked my buddy what the problem might be but he doesn't know. I know nothing about what dither is.

Anyone know what the problem may be?

[mitchAUS]

You only dither once. If it's getting mastered, you shouldn't be dithering. It is the final step used to cover the artifacts that occur when reducing the bit-rate. Why is the mastering friend requesting a 16bit audio file? Send it in the same sample rate and bit-rate that you have been working on in ableton. Dithering is intentional noise to mask the effects of quantization error. If you do this before mastering, as your friend makes your track louder they will boost this noise as well, which is undesirable.

[outbound]

Yup not to mention in order to avoid quantisation error at the end he will have to add further dither on top of the hyper compressed dither you have just added. No need for that at allllll