Yes. the Sonos Five speakers do work horizontally, as well as vertically as a stereo pair. The support documentation says this:

———

Speaker orientation guidelines

You can place a Sonos Five, Play:5 (gen2) or Play:3 in either a horizontal or vertical orientation.

A horizontal speaker will output stereo audio over a wide soundstage while a vertical speaker will output mono audio/single audio channel. When placing a single speaker, we recommend using a horizontal orientation. 

When either horizontal or vertical, make sure all four rubber feet are sitting completely on the flat surface. 

———

I will just add to the above with this slight clarification…

A single vertical speaker will not play in stereo (it’s mono audio only), whereas a single horizontal will have a left/right channel. Two speakers paired in stereo will play in stereo regardless of orientation.

If using the Fives as a stereo pair, then orient vertically with tweeters on the inside for a sharper stereo image, or put the tweeters on the outside for a slightly wider, but possibly more diffuse soundstage.

Hope that helps.

Thanks Ken for the concise answer.  The second 5 arrives in a few hours so I will give all your suggestions a go!

Cheers,

Ivan

Ivan, what orientation did you settle on, vertical pair or horizontal pair?

I went vertical with the Sonos controls each facing the inner side.  After a proper Trueplay using an iPhone 6 I had laying around, the soundscape is quite impressive.  Also note I did set the two Fives as a Stereo Pair.

Hope this helps.

Cheers

Me too, that’s how I like them.

Definitely vertical,with tweeters on inside.This is a killer set up!….I,myself and a pal have it and we are in disbelief as to how good these work.

Good luck