Add DSP settings info

docs/player-support/index.md

@@ -23,3 +23,24 @@ Players can only deleted if they are unavailable or disabled. Deleting a player
 Audio quality is the principal reason why native MA players are developed. These players provide the highest quality playback experience. HA players should work and may work well but they may also have been written with a basic objective such as enabling text to speech. Therefore, if there is a MA player available and a HA integration then you should always choose the MA player. 
 
 A sample rate above 48kHz or a bit depth above 16 is considered High Resolution (Hi Res)
+
+## DSP Settings
+
+All providers have the option to apply [Digital Signal Processing](https://en.wikipedia.org/wiki/Digital_signal_processing) (DSP) filters to the audio stream. The option is found in the MA settings for each player which means that each player has its own independently configurable DSP settings.
+
+DSP settings will be disabled for all groups except AirPlay and Snapcast.
+
+The DSP path has mandatory INPUT and OUTPUT filters and optionally the following can also be added (multiple times if desired):
+
+- Parametric Equalizer
+- Tone Controls
+
+The DSP settings can be enabled and disabled via a toggle which allows easy [A-B testing](https://www.youtube.com/watch?v=KefGjPYyIO4)
+
+The line on the left of the DSP settings represents the audio path from the audio file (top) to the speaker (bottom).
+
+A dot on the line represents a filter that changes the signal. The lack of a dot indicates that the particular filter has been disabled.
+
+Using the icons at the top of the view, the additional filters can be reordered, disabled/enabled or deleted.
+
+![DSP image](../assets/screenshots/dsp.jpg)