Does size matter?

I was wondering if the size of the muffler matters to how its goin to sound. I have heard some people say the larger the muffler, the deeper sound you can get from it. Is this true? I'm getting ready to do my exhaust system and I'm going for something deep, not like the tin-can sound. Its going to be a custom exhaust so I'm looking for any suggestions on a muffler.

It's not the size, it's how you use it :)
Just buy an Apexi cannon-style muffler from any website and weld it onto some 2.5" piping.