This article shows how to use the Modular mixer DSP management to save ressources.

The following animation show how much DSP takes a 24 channels/6 stereo aux  mixer.From there, it is possible to switch some parts off DSP, by using the dsp management of each module.

Here is a project where modules are added. Stem takes the most ressources, which is normal as it is the central part of the mixing network, and here all functions are swicthed "on". Channels are quite light and MB7 is not very DSP hungry, while the resources required by Sidechainers are negligible.
The DSP usage shown is the default one (as devices are loaded, with all channels and features are active, which is there default setting).

After the animation, we're going to see where it is possible to switch a few things off to gain ressources, in order to load a few more effects or allow a few more connections.

1. Stem Bus DSP Management

You have seen in the above animation that Stem is the most DSP consuming device, which is normal because it contains quite a high number of internal connections...

Remember that it is a "stereo" mixer, so it would compare to a 48 input mixer... with 6 stereo aux sends, which would be 12 aux on regular mixers....

DSP management has been pushed so it allows to switch off small things here and there, which at the end of the day, allow to save significant amount of ressources.

In Stems you can save dsp by switching off:

1. Un-used channels, by pressing the "off" button near the channel number
2. Bus sends, by using the panel that is accessible with the big "DSP" button on the toolbar.

Additionally, to help visual organisation, Bus sends that are deactivated are simply hidden from the mixer and not shown, as if they didn't exist at all.

You can free almost 1 DSP by de-activating what you don't need.

Just press on a group to deactivate it. The potis will also disapear from the surface.

Using groups of 4 does not allow to deactivate absolutely all bus sends that are not in use, but it allows to save more dsp than having dsp feature on each aux send, which would take more resources than the present system by groups of 4. Moreover, it is much more comfortable to use groups of 4, rather than having to manage all 168 bus sends separately.

2. Channels DSP

On channel modules, you can turn the channel Off by pressing the Off switch.

Additionally, any filter that shows " - - " in the Filter type display, is automatically loaded off dsp.

Moreover, channels come in various versions which are more or less sophisticated, and so it is possible to optimize DSP usage by choosing the right modules, rather than loading a lot of sophisticated channels where most functions will be left unusued most of the time. That's why channels come with a great variety, to be able to build simple or less simple mixers.

Read more about channels on that page