What can you do with the DSP add-on module?
You might have noticed already that lots of the new boards including the DAC2 Pro, DAC2 HD and Digi2 Pro support our add-on DSP module. But do you need it?
What is the DSP add-on? This board is equipped with a digital signal processor that intercepts the digital data stream from the Pi to the HiFiBerry board and can modify it. There are lots of things you can do with it. If you feel comfortable programming the DSP by yourself, you can pretty do anything that the DSP supports. Not just simple IIR filters, volume controls, compressors, but all even long FIR filters. To do this, you need to use Analog’s SigmaStudio. Note that we do only recommend this to people with previous experience with DSPs. The learning curve is steep, even though it the programming is done in a graphical way.
Alternatively you can use the DSP profiles that we provide. Settings filters can be done even from the command line using our DSPToolkit software. However, we strongly recommend to use HiFiBerryOS. This allows you to implement parametric equalizers graphically. Even without measurement tools, you can directly hear what a specific filter does as all changes are done in real time.
But we think the coolest features that HiFiBerryOS has to offer is the room acoustics equalisation. Especially in the low frequency range, no normal listening room is perfect. There are always some frequencies that create resonances. While changing the placement of the speakers can already help a lot, using additional filters can further improve the playback quality. Using our HiFiBerry measurement microphone, HiFiBerryOS can measure the frequency response of your room and automatically create correction filters that will be deployed to the DSP.
As is fully works on the digital data, there are no losses in signal quality that usually happens with DSPs that have analogue inputs and outputs.
August 5, 2021