Operation Manual

ABOUT AUDIO ON COMPUTERS
281
ReWire and Latency
When you run Reason as a ReWire slave, it is the other program, the Rewire master
that is responsible for actually creating the audio and playing it back via the audio
card. This means that it is the master program’s latency you will get as a final result.
! When Reason runs as a ReWire slave, what audio hardware you have,
what driver you use, and settings you have made in the Preferences dia-
log are of no importance at all! All audio hardware settings are then in-
stead done in the ReWire master application!
For information on ReWire, see “Using Reason as a ReWire Slave”.
Reducing latency
There are a few general methods for making sure latency is as low as possible:
D Remove background tasks on your computer.
This might be any background utility you have installed as well as networking,
background internet activities etc.
D Optimize your songs.
You might run into situations where you have to raise the Output Latency setting
to be able to play back a very demanding song on your computer. Another option
would be to actually optimize the song. See “Optimizing Performance” for details.
D Get a faster computer.
This is related to the point above and only required if you find that you need to in-
crease Output Latency because your computer can’t really cope with the songs
you try to play.
PC Specific Information
About ASIO DirectX, MME and the Sound Buffer
setting
There are three ways for Windows to access the audio hardware:
Via an MME (MultiMedia Extensions) driver
This system has been around since Windows 3.0, and it is this type of driver that is
normally installed in the Control Panel and via Plug’n’Play. Most regular sound play-
back (like when Windows goes “bing” on startup) happens via MME.
• Practically all cards come with an MME driver. If your hardware appears in the Sys-
tem part of the Control Panel, you have an MME driver installed.
• Using audio hardware via an MME driver gives you the longest latency figures.
• Only one program at a time can use audio hardware accessed via MME.
Via a DirectX driver
DirectX is a later system developed by Microsoft to provide developers with more ef-
ficient routines to access audio.
• Not all audio hardware come with DirectX drivers. However, drivers for some hard-
ware are included with DirectX itself.
• Using a DirectX driver gives you a shorter latency, between 40 and 90 millisec-
onds.
! Only use DirectX if you are sure that there is a “certified” DirectX driver
installed for your audio hardware.
✪ More information about DirectX can be found on Microsoft’s DirectX
web pages, at www.microsoft.com/directx.