User guide
Tracktion 4 Reference Manual
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Below the input and output device list, there are some extra settings. These settings will vary slightly
depending on whether you are using a Mac or a PC.
Sample rate: This control sets the sample rate that Tracktion uses for playback and mixing. For audio
intended for CD you will typically want to set this to 44100. Opinion is split on whether working at higher
rates is worthwhile, as it typically more than doubles the load on your computer. If, however, you like to
work at higher sample rates then it is a good idea to increase this value in xed multiples of your de-
sired nal sample rate, e.g., 88200 Hz (44100 x 2) for CD audio.
Be aware that higher sample rates require correspondingly more processing power, so doubling the
sample rate will likely halve the amount of effects, VSTis, and tracks, your computer can process.
Latency: This control denes how much of a buffer will be used by Tracktion when transferring audio to
/ from your audio device. A buffer is necessary to achieve reliable recording and playback performance.
If your computer is temporarily unable to keep up with the demands of real-time audio, and there is no
buffer, or if the buffer size is too small, data loss is likely to occur. This data loss will be audible to you
as pops and clicks.
Setting the ideal buffer size unfortunately requires a trade-off; on the one hand you need a buffer
large enough to provide error free performance, but on the other hand, if the buffer size is too large,
you may begin to notice a delay between Tracktion processing a sound, and the sound being au-
dible through your monitors. This delay is called “latency,” and it is this latency that is being referred
to above. Too much latency may be noticeable to you when playing live, so ideally the latency value
should be set as low as your computer can handle without introducing errors into your recordings.
Perhaps the best strategy for determining the ideal latency setting is to start high, and over time,
adjust the value downwards until you reach a level that is comfortable when playing live, and yet yields
reliable, error free playback and recording.
Restart device: Clicking this button causes Tracktion to re-initialise the drivers for your audio hard-
ware. This can sometimes help if the audio driver crashes. In addition for PC users, if you have made
changes to your hardware settings through the ASIO control panel, then you may need to restart the
audio device before Tracktion will recognise the changes.
Show only enabled devices: When this option is checked, input and output devices that are set to dis-
abled will not be shown in the list of I/O devices above. This can be handy when there are a lot of input
and output devices, and you are only interested in those you have enabled.
Use 64-bit maths when mixing tracks (uses more CPU): When this option is enabled, all summing
inside Tracktion is performed at 64-bit oating point, instead of the standard 32-bit. This can increase
summing accuracy in edits that contain lots of tracks, though for the most part the improvements will be
below the threshold of human hearing.
Processors to use: If your computer has more than one CPU, or the CPU has multiple cores, you can
use this control to specify how many of these processors are utilized by Tracktion. You will be able to
set this value to a number between 1 and the total number of CPUs your computer has available. For
example, if your PC has a single “dual core” processor, you will be able to choose between Tracktion
using one or both of those cores. Typically you will want to set this value to the highest possible position
to ensure that Tracktion can take full advantage of your available computing power. However, if you are
running some other CPU intensive application alongside Tracktion, you can reduce the number of pro-
cessors that Tracktion uses, which will free up the remainder for the other software.