I'm just wondering: When I'm driving my 94 accord ex, once i hit 2000 rpm, it makes this kinda loud muffler sound. It dose it only at 2000 rpm. i'm just wondering what that is. I kinda like that sound. (stock muffler)

 

heat shield on cat........

 

I've had the same thing on my car since I bought it. I'm not sure if it's the heat shield on the cat or exhaust spring-bolts going soft.
I don't know anybody who can do this for me personally, but if you can get the front end up in the air and have someone hold the engine so the noise is constant, just scoot under there and eyeball where it's coming from.

 

put a metal band around the cat and the noise will go away. it's a common problem