Turn off atmos for music?

It depends on the type and source of the music.  When I'm listening to Qobuz through my computer to the AVR (Denon) using HDMI I listen in stereo (2.2).  If it's a multichannel DVD, SACD or BlueRay disc from your disc player you are listening to then Dolby or DTS will select the discrete sound channel parameters.  If you are listening to the radio then you should choose stereo.  But then again you could choose a 7 channel stereo setting if that is what you want.  I have B&W speakers (full range and surround) with Polk in ceiling back and Atmos and have had no issues with timbre between them.  Happy listening.

While there are some multi channel recordings of music out there the vast majority of recordings are in stereo (2 channel). If you are listening to 2 channel recordings through a home theater receiver with surround speakers on then any sound coming from the surround speakers is created by the receivers DSP "digital signal processor" in other words it is created artificially and is not part of the recording and thus undesirable by most audiophiles. But it's up to you if you like it or not. Systems designed for home theater and systems designed for stereo music have different priority's. Music systems try for purity of the musical presentation and home theater systems are more about special effects. Thus most typical HT systems are not the best for music it's just not their main focus. It doesn't mean they can't be good at music it just means you have to work at it and understand what it takes to put a good system together that can do both. Many like myself prefer a combo two channel theater system. Properly set up can be great for both with in certain limits. 

Yes thanks for responses. I should specify I actually like to listen to music in multichannel. I know this isn't the purist way. I like the spacious sense of size and envelopment with the multichannel. I run a focal aria system 5.2.2. I don't get bothered by the ceiling speakers but I do wonder if there is an avr setting to turn them off to play in 5.2 for example. 

You may have an avr that allows you to pick the allowable channels for a given input when you are in setup mode.  Check out your avr manual.  A final point from me would be if you have a disc player with 5.1 analog out connections and a receiver with 5.1 analog in and you play some multichannel program material you will get to listen to 5.1 only.  Hope this helps.

Most HT receivers and processors have a stereo mode which disables all but the L/R and subwoofer speakers.

They have additional modes which can be thought of as "fun" such as Neo6 and Dolby music modes which engage the center and surround, and possibly the height speakers as well. 

No one can tell you if you’ll like them, and it’s not like you’ll hurt the recording if you do, so go ahead and experiment. I personally like the Neo6 music mode and how it fills in the center. Few others do. :-)