There are three filter types available in Reference 4
- Zero Latency mode
- Linear Phase mode
- Mixed mode
Each filter type differs audibly and has individual technical aspects: phase response, pre-ringing, latency figures, and processing power required. You can learn more about the topic by reviewing this article: Filter types and phase response in Reference 4
Which filter type is recommended to use?
There is no definitive correct or incorrect way of using different filter types - settings will depend on your individual mixing and monitoring needs and preferences.
However, for a simple and stable workflow (at least while getting familiar with the software), we do recommend using Zero Latency or Mixed modes for the majority of the mixing process, then switching to Linear Phase towards the end of the mixing process, to check for any phase-related issues.
Feel free to submit a support request if you still have any questions!