I'm working on setting up my gym (13x14 room) and currently have M3s in there. I tested it out using my EP500 as well as an EP350 (borrowed from my other rooms) and both sounded great but no noticeable benefit to the 500 over the 350 in that size room. I definitely want a subwoofer but since it's a gym would prefer not to buy a 350. Would an EP125 be noticeably worse than the EP350 in that size of a room?

With the right amp the m3's can put out a nice bit of bass on their own. Turn up the bass. What are the floors and how many people in this room at a time?

I have 3/8 inch rubberized floor throughout. I tried turning up the bass, it's not bad, but pretty big difference with a subwoofer. Generally it's just me working out, but occasionally I will have up to 5 in there on computrainers.

I was hoping someone with a ep125 would chime in. I only have tried the 500. Personally for that room I'd just grab a 350 or 500 from the refurb or b stock area. I agree though....always better with a sub.

I did some more tests and have come to the conclusion that even the 350 is overkill for that size room. I ended up ordering an ep175, I think it will be the perfect size.

On another note I alternated between my M3s and M60s and without the subwoofer there is a big difference. With the subwoofer (I used the ep350 for the test) , they are so close. I guess with a good subwoofer you really can get away with bookshelves.