Reference Manual

579 Audio Fact Sheet
Pitch modes. Although the Complex modes may sound better, particularly when used with mixed
sound files containing many different kinds of audio material, they are never neutral — not even
at the original tempo. Because of this, and because of the increased CPU demands of these
algorithms, we recommend using them only in cases where the other Warp modes don‘t produce
sufficient results.
33.3.2 Sample rate conversion/transposition
Sample rate conversion (during both real-time playback and rendering) is a non-neutral opera-
tion. Playback of audio files at a sample rate that is different from the rate set in Live‘s Preferenc-
es window will cause signal degradation. Transposition is also a form of sample-rate conversion,
and thus also results in non-neutral behavior.
To minimize potential negative results, it is recommended to do sample rate conversion as an of-
fline process in another application. Once the samples have been converted to the sample rate
that you plan to use in Live, the files can be imported without any loss of quality.
Rendering audio from Live with a sampling rate other than the one that was used while work-
ing on the project is also a non-neutral operation, and may result in a loss of sound quality. It is
recommended to always render using the original sampling rate, and then convert the rendered
file using a dedicated mastering application that is optimized for these kinds of CPU-intensive,
offline tasks.
While we recommend that you use a high-quality offline tool for sample rate conversion, we rec-
ognize that one of Live‘s core features is its ability to pitch-shift and warp audio in real time. For
this situation, it is necessary to make a trade-off between CPU performance and precision. We
recommend the use of the Hi-Q button (page 111) for any clips which undergo transposition
in a given Set. The algorithm behind the Hi-Q switch was rewritten for Live 7, and now results in
considerably lower distortion than in previous versions.
33.3.3 Volume Automation
Automation of volume level results in a change in gain, which is necessarily a non-neutral opera-
tion. But certain implementations of automation envelopes can result in audible artifacts, particu-
larly if the envelopes are not calculated at a fast enough rate. Since Live 7, volume automation
curves are updated for each audio sample, resulting in extremely low levels of distortion.