Getting the most out of OASYS PCI's DSPs
OASYS PCI Website
Contents
Keep an eye on the Resource Monitor window
Sample rate affects processing power
Record OASYS PCI synths and effects to disk
Use Send and Output Busses to share Effects
Turn off unused Mixer Channels
Output Bus "To Master" can change DSP processing requirements
Keep an eye on the Resource
Monitor window
The Resource Monitor window gives you an instant display of OASYS PCI's DSP and CPU usage. This lets you know how much DSP power you're using, and how much is still free.
It also shows the results of any of the optimization techniques explained below, so that you can figure out which ones are most effective in a particular case.
Adjust number of
voices
This is the most immediate and effective way of optimizing DSP usage for OASYS PCI.
The OASYS PCI uses fixed voice allocation, which means that if you want to play six-note chords on an electric piano sound, you must tell the system to reserve six voices for that Program. This is done through the Patch's Number of Voices parameter, in the Edit Program window.
You should try to set the number of voices just as high as necessary, and no higher. The fewer voices you reserve for one Patch, the more that will be available for other Patches, or for Effects.
Sample rate affects processing power
The sample rate affects the processing power available to the OASYS PCI. You'll get about 8% more processing power for synthesizers and/or effects at 44.1kHz than at 48kHz.
For examples of how this effects how many voices you can play, and how many effects you can use, see How many effects can I use at once? and How many voices can I play at once?
Record OASYS PCI synths and
effects to disk
If you've maxed out OASYS PCI's DSP processing power, and still want to add more OASYS PCI synths and effects, here's an easy solution: record the existing OASYS PCI tracks into your digital audio program, clear off the DSPs, and start over again.
To do this:
1. Record the OASYS PCI synths and effects into your audio program.
Via ASIO, you can record up to 12 channels (six stereo) simultaneously, all in the digital domain. If you're using OASYS PCI with another audio program, use ADAT, S/PDIF, or analog I/O.
For more information, see the OASYS PCI Users Guide, under "Using Audio Programs."
2. Save the OASYS PCI Multi in its current state, just in case you want to edit the recorded tracks at a later time.
3a. If you've only used a few channels in the OASYS PCI Multi, switch the channel outputs to Off. This will clear the Patches and Effects from the DSPs, freeing up space for new plug-ins.
or
3b. Close the old Multi, and start a new one from scratch.
Use Send and Output Busses to
share Effects
Each Mixer Channel can have its own Insert Effects, which allows for very powerful and flexible sound-shaping. However, if several Channels each use a number of resource-hungry Effects, this can eat up DSP resources pretty quickly.
If several Channels are using similar Insert Effects, it may make sense for them to share the effects through a Send Bus or Output Bus instead. This will free up DSP resources, which can then be used in other ways.
For more information, see the OASYS PCI Users Guide, under "Using Effects."
Optimizing physical bus
usage
The OASYS PCI s a certain number of physical busses, used to communicate between the DSP chips on the card. These physical busses are used to create the Mixer Channels, Send Busses, and Output Busses.
The Detailed view of the Resource monitor shows how many of the physical busses are in use. You can turn off Mixer Channels and Send Busses to optimize the use of these physical busses.
Turn off unused Mixer
Channels
If a Mixer Channel's Input Type is set to "Off," or if the Output and Sends are all set to "Off," the Channel will be turned off, and will not use a physical bus.
Turn off unused Send
Busses
If the Send Bus Output is set to "Off," or if no Mixer Channels are assigned to a Send Bus and the Send Bus's Stream Input is set to "None," the Send Bus will be turned off, and will not use a physical bus.
Output Bus "To Master" can change
DSP processing requirements
Activating an Output Bus's To Master function may sometimes require the Programs and Effects to be re-arranged within the DSPs. This may either increase or decrease the effective amount of DSP processing power available. In extreme cases, if a Multi was already using up almost all of the available DSP processing power, this may put the processing requirements over the edge, so that the Multi is too big to be played.
If this happen, you can reduce the number of Output Busses routed to the Master output, or use other methods described in this section to reduce the DSP processing load.
Disable meters
If things are running very tight with CPU processing power, you can disable meters entirely. To do this, select Disable Meters from the File menu.
If you pull down the File menu again, you'll notice that the item's name has changed to Enable meters. To re-enable the meters, select Enable Meters from the File menu.
Copyright 1999-2002 Korg Inc. FAQ Version: 8/19/02