User Manual

OPTIMIZING PERFORMANCE
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! Raising the buffer size to eliminate audio artefacts on playback is mainly effective if you are currently using
very small buffers, 64 to 256 samples. If the buffers are already big (1024 or 2048 samples) you will not notice
much difference.
Making Buffer Size adjustments in the Record Preferences dialog
If you are running Record under Windows and are using an ASIO driver, or if you are running Record under Mac OS
X and are using a Core Audio driver, you can adjust the input and output latencies in the Preferences – Audio dialog.
D This is done by dragging the Buffer Size slider.
General procedure for reducing latency
The basic procedure for optimizing the latency is the following:
1. Open a song and start playback.
You want to choose a song that is reasonably demanding, i.e. with more than just a few tracks and devices.
2. Open the Preferences dialog.
Under Mac OS X, this is found on the Record menu; under Windows it’s found on the Edit menu.
3. Select the Audio page and locate the Buffer Size slider.
! If you are making adjustments in the ASIO Control Panel for hardware with an ASIO driver (Windows only), you
should make a note of the current buffer settings before changing them.
4. While the song is playing, listen closely for pops and clicks and try lowering the latency (Buffer Size).
5. When you get pops and clicks, raise the Buffer Size value a bit.
6. Close the Preferences dialog (and ASIO Control Panel, if open).
About Latency Compensation
Below the Input Latency and Output Latency rows in the Preferences-Audio dialog, you will find two items called Re-
cording Latency Compensation and External Sync Offset. These value are used internally in Record to compensate
for latencies when recording audio using external monitoring, and when synchronizing Record to another MIDI se-
quencer or similar.
Recording Latency Compensation
! Adjusting the Recording Latency Compensation parameter is never necessary when you have selected “Auto-
matic” in the Monitoring section on the Audio page in Preferences - see “Monitoring”.
Recording Latency Compensation is when the program adjusts the position of recorded audio according to the cur-
rent latency. Here's how it works:
If you're recording audio and not monitoring through Record (e.g. monitoring directly through the audio card or via an
external mixer), the audio you record will reach the program slightly late. This is because you play along with back-
ground tracks or the metronome - and you hear these delayed by the output latency. Also, the sound you record is
sent to the program via the buffers in the audio hardware - it is delayed by the input latency.