sub mini

If you have the Sub Mini bonded to the Beam as one room there would only be one EQ setting option.  How are you setting separate EQ settings for the Beam & Sub?

The poster above is correct.  There is no individual bass adjustment for the Beam, that adjustment would be for the whole room.  Bass is routed from the Beam to the Sub Mini by the crossover, not the level on the Beam.  Increase the overall level to normal, and then adjust toe Sub level to your liking (or use Trueplay to adjust things automatically). 

It really depends upon your source as to how much low end you get from any sub. Is the source music, movies or both. If movies are they streamed in stereo or Dolby Digital 5.1. The Beam Gen 1 will not output Dolby Atmos.

On another note you mentioned that you were getting distorted sound from the Beam. Did you contact Sonos to determine if there was a blown speaker? Adding a Sub would not resolve your low end issue.

​@Joe Chris as others have indicated you need to rely on the crossover point to reroute the bass from the beam and not the EQ. This will be preset by Sonos based on the capabilities of each product. But, if you have a blown speaker in the beam IMHO  this is not a good solution to your issue as the speaker will still be required to handle some of the signal in the low mids as a minimum and the distortion will still be there even if it is less pronounced. The presence of the distortion will have a negative impact on your listening experience and this may get worse as the speaker or deteriorates. This is because the sub does not “replace” the speaker in the beam it just allows it to be used to target a more specific part of the audio spectrum. Speak to Sonos to see if the speaker is damaged and determine what, if anything, can be done if it is. 

I currently have the EQ bass level set at -10 and the sub level set at +15. I understand now the EQ bass is for the whole audio.  I thought it was just the beams bass level.  Either way the main issue was I was trying to cover the distortion from the beams bass to the sub mini.  At these settings I definitely see improvement on movies for sure, but for music you can still slightly hear at higher volumes.  I do not have a crossover adjustment on my app.  Where would I adjust that from?  

There is no cross-over adjustment for a sub bonded to a Beam but there is a phase adjustment in Sub Audio. FYI to provide complete information on the subject there is a crossover adjustment when a sub is bonded to a Sonos amp.

You do have a “loudness” adjustment when listening to audio at low volumes. However as I previously mentioned you should verify if the Beam has a blown speaker or damaged chip.