.......

[Shannon]

I play subs from my cell phone almost exclusively. It has a mono speaker, and the results are acceptable for me. It's not the best it could be though. I keep my cell phone in my pocket, perched on top of my wallet, so the speaker sticks out of my pocket and isn't obstructed. The only issue you get from this is the possibility of having your pants or shorts adjust the volume setting without you knowing it when you sit down, so when I sit down, I just take my phone out of my pocket and point it at myself on the table.

If your speakers are stereo, they will be better than mono. The more perfect the stereo separation you get, the better your results will be, which is why headphones/earbuds are best, as long as you keep the volume safe with them while using ultrasonics.