Adobe AUDITION 1.5 - Manual (Page 46)

CHAPTER 2 38
Setting up Adobe Audition
Limit Playback To Downsamples audio data for playback. Use this option to compensate
for limitations imposed by your hardware. For example, if your sound card doesn’t handle
32-bit audio correctly, you can have Adobe Audition limit the playback of 32-bit files to
either 16-bit or 8-bit.
Send 32-bit Audio As Specifies how Adobe Audition sends 32-bit audio data to the output
device. This option is not available if you select a Limit Playback To option. If the output
device supports it, you can send 32-bit audio as 3-byte Packed PCM, 4-byte PCM, or 4-byte
IEEE float.
Enable Dithering Activates dithering when playing back audio at a limited bit depth. If
you deselect this option, Adobe Audition truncates the audio data instead. This means that
bits that aren’t used are simply chopped off and discarded. Enabling dithering is recom-
mended when working with audio files that have a higher bit depth than your sound card
supports. You can set the following options when dithering is enabled:
• bits specifies the number of bits to dither to. If you have a 20-bit sound card, for
example, you will want to dither to 20 bits since any more bits will not be used by the
card. Even for 16-bit-only sound cards, choosing to dither to 16-bit will improve the
quality when playing back 32-bit audio.
• p.d.f. (probability distribution function) controls how the dithered noise is distributed
away from the original audio sample value. Usually one of the Triangular p.d.f.
functions is a wise choice, because it gives the best tradeoff between SNR, distortion,
and noise modulation.
• Shaping specifies a noise shaping curve for moving noise to different frequencies. You
can also specify that no noise shaping is used.
Setting properties for audio input devices
The Device Properties dialog box lets you specify Adobe Audition’s parameters for
recording waveforms. If you have multiple sound cards, or a single card that has multiple
inputs, you can customize the properties for each audio input device.
To set properties for audio input devices:
1 Choose Options > Device Properties, and click the Wave In tab.
2 Select a device from the list at the top of the dialog box.
ug.book Page 38 Tuesday, March 16, 2004 1:29 PM