Reference Guide

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Preferences dialog

File System

• Enable Read Caching and Enable Write Caching. Choosing either of these options lets

SONAR use the Windows disk cache while reading or writing audio data. SONAR will usually

perform best with all caching disabled, which is the default setting. If your computer has an older

IDE disk controller, or a disk controller that does not use DMA transfers, enabling caching may

improve SONAR’s audio performance.

• I/O Buffer Size. This value determines the buffer characteristics for transfers to and from the

disk. Changing this value does not affect audio latency, but will affect the disk throughput for audio

tracks. The default setting is 128. A higher value causes more audio to be buffered from the disk

ahead of the playback cursor. If you are hearing consistent dropouts/clicks in your audio and if

your project contains high bit depth (32/64 bit) or high sample rate audio (88.2K or higher), it may

be indicative of a too small I/O buffer size. If so, try a higher I/O buffer size like 256 or 512. If audio

problems persist, reset to 128 and try a different remedy.

Also, if you are playing a large file, and using maximum latency, a too-small I/O buffer size may

cause dropouts or crashes. Try increasing the buffer size by blocks of 128.

Record Latency Adjustment (samples)

If you loop an audio output back into an audio input, and re-record a track this way, the audio doesn’t

line up. For some sound cards, it is off quite significantly. This record latency adjustment is a

compensation for that delay.

You can do an approximate measurement of the delay by turning on samples as the resolution unit

in the Time Ruler, and comparing the original track with the re-recorded track. Then you can enter a

value in the Manual Offset field to compensate.

If you use ASIO mode, enter 0 in the Manual Offset field and leave the Reported Input Latency

check box checked (this check box only appears in ASIO mode). This will line up audio in most

cases. If you think you can tweak it closer, use the Manual Offset field.

In ASIO mode, the current active ASIO device (remember ASIO can only have one active at a time)

reports its “Input Latency.” You can't edit this value. This supposedly accounts for buffer size, A/D

Conversion latency, etc. The check box allows you to use this reported value. It is checked by

default. In any case, the amount entered into the Manual Offset field will be combined (added to)

the reported value if you have it checked.

For more information, see:

“Synchronization overview” on page 1080