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Setting up your system
Short response times (latency)
Another aspect of performance is response time. The term
“latency” refers to the “buffering”, i.e. the temporary stor-
ing, of small chunks of audio data during various steps of
the recording and playback process on a computer. The
more and larger those chunks, the higher the latency.
High latency is most irritating when using software instru-
ments and when monitoring through the computer, i.e.
when listening to a live audio source via the Sequel mixer
and effects. However, very long latency times (several
hundred milliseconds) can also affect other processes like
mixing, e.g. when the effect of a fader movement is heard
only after a noticeable delay.
A system that responds fast will always be more convenient
to work with.
• Depending on your audio hardware, it may be possible
to “trim” your latency times, usually by lowering the size
and the number of buffers.
For details, refer to the audio hardware documentation, or, if you are using
a DirectX driver under Windows, the dialog help.
System factors that affect performance
CPU and processor cache
It goes without saying that the faster the computer’s pro-
cessor, the better. But there are a number of factors that
affect the apparent speed of a computer: the bus speed
and type (PCI is strongly recommended), the processor
cache size and of course, the processor type and brand.
Sequel relies heavily on floating point calculations. When
shopping for a processor, please make sure you get one
that is powerful in calculating floating point arithmetics.
Note also that Sequel features full support for multi-pro-
cessor systems. So if you own a computer system with
more than one processor, Sequel can take advantage of
the total capacity and evenly distribute the processing
load to all available processors.
Hard disk and controller
The number of hard disk tracks you can record and play
back at the same time also depends on the speed of your
hard disk and hard disk controller. If you use E-IDE disks
and controllers, make sure that the transfer mode is DMA
Busmaster. Under Windows, you can check the current
mode by launching the Windows Device Manager and
looking for properties of the IDE ATA/ATAPI Controller’s
primary and secondary channel. DMA transfer mode is en-
abled by default, but may be turned off by the system
should hardware problems occur.
Ö In Sequel you can record up to eight stereo tracks at a
time.
Audio hardware and driver
The hardware and its driver can have some effect on reg-
ular performance. A badly written driver can reduce the
performance of your computer. But where the hardware
driver design makes the most difference is with latency.
This is especially true when using Sequel for Windows.
• Under Windows, ASIO drivers written specifically for
the hardware are more efficient than a DirectX driver and
produce shorter latency times.
• Under Mac OS X, audio hardware with properly written
Mac OS X (Core Audio) drivers can be very efficient and
produce very low latency times.
Optimizing processor scheduling (Windows
only)
To get the lowest possible latencies when using ASIO un-
der Windows XP (on a single CPU system), the system
performance has to be optimized for “Background ser-
vices”:
1. Open the Windows Control Panel from the “Start”
menu and select “System”.
2. Select the “Advanced” tab and click the “Settings”
button in the “Performance” section. The “Performance
Options” dialog is opened.
3. Select the “Advanced” tab.
4. In the “Processor Scheduling” section, select “Adjust
for best performance of: Background services”.
5. Click “OK” to close the dialogs.
!
Again, we strongly recommend that you use audio
hardware for which there is a specific ASIO driver!