Specifications

OPTIMIZING PERFORMANCE
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Introduction
Reason is a program of infinite possibilities. You can create as complex songs
as you like, using endless racks of devices. While this is one of the most exciting
properties of the program it does have a drawback – it means that you must be
careful with how you manage your computer processing power.
Each device you add to the rack uses up a bit of computer processing power –
the more devices the faster the computer has to be. However, you can set up
your devices to require more or less processing power. For example a sound on
the Subtractor synthesizer that only uses one oscillator and one filter requires
much less processing power than one using both dual oscillators and dual fil-
ters.
Samples used in your songs also require RAM - memory - to load properly. The
use of RAM can also be managed, as described at the end of this chapter.
When creating songs for other people, for example for publishing in the Reason
song archive (see www.propellerheads.se for more information), you should do
what you can to reduce the requirements for playing back a certain song, both in
terms of processing power and in terms of RAM requirements. Other users may
not have as powerful a computer as you do!
Checking Processing Power
On the transport you will find a meter labelled CPU. This indicates how much
processing power is used at any given moment.
The CPU meter.
The higher this meter goes, the higher the strain on your computer processor.
You will note when your processor is heavily loaded that graphics will update
slower. Finally, when there’s too little power left to create the audio properly, the
sound will start breaking up.
Optimization and Output
Latency
As described on page 282, you generally want the lowest possible latency, to
get the best response when you play Reason in real time. However, selecting
too low a latency is likely to result in playback problems (clicks, pops, dropouts,
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 de-
vices you use), the higher the minimum latency required for avoiding playback
difficulties.
Therefore, you may need to adjust the latency. This is done differently depending
on which audio cards, drivers and operating system you are using:
Making adjustments in the ASIO Control Panel
If you are using an ASIO driver specifically written for the audio hardware, you
can in most cases make settings for the hardware in its ASIO Control Panel.
This panel (opened by clicking the ASIO Control Panel button in the Prefer-
ences-Audio dialog) 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 fewer and smaller the audio buffers, the lower the latency. Please
consult the documentation of your audio hardware and its ASIO drivers for de-
tails!
! 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 adjustments in the Reason Preferences dialog
If you are running Reason under Windows and using an MME or DirectX driver,
or if you are running Reason under Mac OS X and using a CoreAudio driver, you
can adjust the output latency in the Preferences – Audio dialog.
D Under Windows and Mac OS X, this is done by dragging the Buffer
Size slider.
D If you are running Reason under Mac OS 9.x using the Sound Man-
ager Default Output driver, you cannot change the latency.
General procedure
The basic procedure for optimizing the latency is the following: