How many UAD plug-ins you can run with any given UAD-2 device greatly depends on which plug ins you are using in particular and what sample rate you are working at. Most UAD plug-ins will use more DSP at higher sample rates (just as native plug-ins use more CPU at higher sample rates) so working at 44.1kHz will allow you to run the most instances of UAD plug-ins. Working at a higher sample rate, such as 96kHz for example, will essentially cut the amount of UAD plug-ins you can use simultaneously in half or more. The chart below will help you understand just how varied the DSP usage of each UAD plug-in can be - note that all values in the chart are taken at a 44.1kHz sample rate:
UAD-2 Plug-In DSP Chart
Note for Apollo Users: Apollo interfaces use DSP and memory resources for its internal mixer. Therefore, the UAD Meters will show some DSP and memory usage when Apollo is connected even if UAD plug-ins are not loaded.
Aside from adding additional UAD-2 devices to your system and/or working at lower sample rates if possible, there are a couple of things that may help you get the most out the DSP you have now:
- Disable "DSP LoadLock" by opening the UAD Control Panel and navigating to the Configuration tab. Uncheck the box next to DSP LoadLock to disable the feature. Having this feature enabled causes certain modular plug-ins such as the API Vision Channel Strip, Neve 1073 Preamp & EQ, or SSL E Series Channel Strip to use their full amount of DSP when loaded regardless of which sections of the plug-in are currently in use, while having this feature disabled causes these plug-ins to only use enough DSP to process the sections of the plug-in that are currently active. If you want to be able to enable certain features or sections in these modular plug-ins after they have already been loaded without needing to worry about your overall DSP, PGM, & MEM usage then it is best to leave this feature on, but turning it off will free up the resources from the unused sections of these plug-ins to be used by other plug-ins, typically allowing for overall higher UAD plug-in counts.
- (Apollo users only) Disable "Input Delay Compensation" in Console if you are not using UAD plug-ins in Console while tracking. This feature is used to keep multiple inputs phase aligned when using internally upsampled UAD plug-ins in Console, and also makes sure that the correct delay amount is reported to the DAW so that audio is placed correctly into the DAWs timeline. Disabling this feature when not needed will conserve a small amount of DSP. To disable, open Console, navigate to Settings > Hardware and select "Off" from the Internal Delay Compensation menu.
For more ways to conserve and optimize your DSP when using UAD plug-ins, see the Getting the Most Out of Your Available UAD-2 DSP article.