Operation Manual

MENU AND DIALOG REFERENCE
271
D If you are running Reason under Windows using a Direct Sound or MME
driver, or Mac OS X using a Built-in audio driver, you can adjust the la-
tency value by using the Buffer Size slider or the up/down arrow buttons.
The highest and lowest possible values depend on the driver.
D If you are using an ASIO driver specifically written for the audio hard-
ware, you can in most cases make settings for the hardware by clicking
the Control Panel button. This opens the hardware’s ASIO Device Con-
trol Panel, which may or may not contain parameters for adjusting the la-
tency. Usually this is done by changing the number and/or size of the
audio buffers - the smaller the audio buffers, the lower the latency.
Please consult the documentation of your audio hardware and its ASIO
drivers for details!
OK, so why not just set the latency to the lowest possible value? The problem is that
selecting too low a latency is likely to result in playback problems (clicks, pops, drop-
outs, etc.). There are several technical reasons for this, the main one being that with
smaller buffers (lower latency), the average strain on the CPU will be higher. This also
means that the more CPU-intensive your Reason song (i.e. the more devices you use),
the higher the minimum latency required for avoiding playback difficulties.
Latency Compensation
This control should normally only be adjusted when synchronizing Reason to external
MIDI Clock.
Because of the latency problem, you might need to adjust Reason’s playback in rela-
tion to the MIDI Clock sync master, so that they are in perfect time. The tempo will not
differ between the two, but Reason might play ahead or behind the other application.
You might need to adjust this. However, this is something you only need to do once.
The setting is stored with your other preferences, so you don’t need to adjust it again.
Proceed as follows:
1. Set up the other application so that it generates a solid click, on for example
quarter or eighth notes, preferably with a special sound on the downbeat.
This click can either come from an internal metronome or from a MIDI
source. If you use a MIDI source, make sure you pick one that has solid MIDI
timing.
2. Set up Reason so that it plays a similar rhythm as the other application. You
might for example use the Redrum drum computer for this.
3. Start the two applications in sync.
4. Make sure you hear both applications at approximately equal level.
5. Open the Preferences dialog in Reason and select the Audio page.
6. Trim the “Latency compensation” setting until the “clicks” from the both
sources sound at exactly the same time.
7. Close the Preferences dialog in Reason.