I have a low cost alternative to the EIH for anyone on a tight budget.
Use
these combined with something like
these .
First the ear buds go in, then the ear protectors over that.
I have used this set up very succesfully for live drum monitoring for the last several months, as well as for setting up mics by myself for recording.
This worked excellently to help me find the best mic placement while playing the drums myself (I'm not a drummer, I had no choice this instance)
The only hurdles with this setup:
You will need a headphone extension cord and a way to support the connection up and behind the drummer, or fasten it somehow to a belt loop. The cord is very short.
The isolation is excelent and the sound of the earbuds is pretty good too, great low end. The foam makes them fairly comfortable.
You also don't need as much output from your headphone amp since the speakers are right in your ears.
I picked up "The Plug" at Kmart for about $15.00
For around $30.00 bucks a good budget solution for drummers.