Dunno if anyone has asked about this sound isolation thingy.

I'm hunting for a pair of headphones with excellent noise isolation from outside. You see, I'm doing mixing/monitoring/balancing on a live environment. And the position of the sound crew is fixed right beside the musicians. Since I can't move to a quieter spot, I guess the only option I have is to get headphones with strong isolation.

The details which I checked online are pretty limited. Most of them are talking about sound isolation from the headphones to outside. But I'm gathering details of isolation from outside to inside instead. And the other recommendation is to get noise-cancelling headphones, which I doubt will work because those are meant for a different frequency. I believe those are meant for planes and MRT and will not work on a situation where there is a live band next to you. They aren't rockers, but enough to disrupt.

Was previously using a cheap Philips headphone. One of those stock models which you can get from any IT store. Didn't work for me. Then, I tested with my personal BeyerDynamic DT770 and it worked well. But those cans are too expensive to leave it around. Right now, I'm using a temporary Creative HQ1600 (another one of those from IT store).

I'm currently planning to get either an Audio Technica M50 or Sony MDR 7506. I've tested the M50 before but it was in a quiet surrounding. The 7506 on the other hand is like world standard for mixing recording. But it might work only in studios, not live environment.

Has anyone used either one of those models before? Other suggestions most welcomed. Take note that I'm looking for sound isolation, not pleasure listening. And would prefer a flat frequency (optional). Budget around RM400-RM600.