Dunno about the PSR2k but my 740 has an unbalanced mono mic input at 50k and since the 2000 was a follow on from the 740 they're probably the same. The gain is very low so you probably need a mic transformer at the very least with a dynamic mic in spite of what it says in the manual. The 740 case is molded to take batteries but the hole is covered with a metal plate. I think the intention was to use them but they decided that it took too much power so it got canned. Same with the 2000.