Dithering.

[mmccarrell]

Someone please explain what the dithering plug-in does, and is it necessary to use it?...

[QuikDraw]

When you reduce the bit depth of an audio file, say from 24-bit down to 16-bit, distortion is introduced in the form of quantization error. Dither eliminates the distortion at the cost of a small amount of uncorrelated noise. The noise that dither introduces is usually beneath the noise floor, so you can't hear it.

Generally, any time you reduce the bit depth of an audio file you should apply dither to eliminate the distortion. This is really an oversimplification, but that's basically how it works.

If you were bouncing a 24-bit session down to a 16-bit file, you should have a dither plug-in as the last insert on your master fader.

Mike

[qgrm]

if you're using a limiter plug in your mastering session (going from 24 to 16), these plugs sometimes include dithering as part of the plug (eg waves L1). if this feature is turned on, you should not dither again (i cant really hear problems with double-dithering in my monitors, but thereotically its bad news:)

B.

[Dr Beamus]

Question:

Which insert is the "last" one...the top one or the bottom one?

Enquiring minds want to know!

Thanks,

Beamus

[Bazzle]

"When more than one insert is used on a track they process the audio in series each effect being added to the previous one,from top to bottom in the mix window".Page 10 Digidesign Plugin Guide

[tele_player]

The bottom one.

Question:

Which insert is the "last" one...the top one or the bottom one?

Enquiring minds want to know!

Thanks,

Beamus

[Daniel Wellman]

And one little bit which tripped me up for a while is that dither should be applied when mixing down to disk using "Bounce to Disk" for 16-bit mixes, even if your session is 16 bits! This is because Pro Tools processes internal data at a higher bit-depth. Since dither is used (someone wiser please correct me if I'm wrong!) for handling low-level signals, this could be most noticeable on *very* quiet passages or at the very end of a fadeout.



From the Pro Tools Reference Guide, p. 461

When to use a dithering plug-in
You should use a dithering plug-in when mastering to a 16-bit file with the Bounce To Disk command, or when mastering to an external device that records at 16-bit.

This is even necessary when using 16-bit sessions. Even though 16-bit sessions use 16-bit
files, they are still being processed internally at a higher bit rate:

• 24-bit for Pro Tool TDM systems
• 32-bit floating for Pro Tools LE systems

For this reason, whether you are using a 16-bit session or a 24-bit session, it is recommended
that you use a Dither plug-in when mastering to 16-bits.

Tricky!

-d

[Dr Beamus]

All right, Bazzle, I'm busted....it was in the manual.

B