Not worth your time
the worst part was of course the story line. this movie doesn't even get gory (if you can call it gory at all) until it is 2/3's into it. and even then, you only have about a solid 5-10 minutes worth of actual 'horror' scenes. the premise was pretty awful to. in order to do the invocations, they had to be in this 'magically acoustic' room, of which there is nothing 'special' about in design, it is just an old sound recording room, thousands of rooms like it with the same exact 'sound' to them. also there was no specific reason why anyone would want to do the invocations. nothing to gain whatsoever, no special powers, no trip to some other reality, no trip to hell... only you uncontrollably killing people, seeing flashes of horrible things and acting more crazy than possessed, oh and did I mention seizures and cutting yourself? the ending was even horrible. the woman electrocutes the guy (and the demon) by knocking an old style metal microphone, the ones with the slits in them, onto a puddle of water. no way would it have ever caused that to happen. and then it even sends a charge back to the console to blow the sound studio equipment out, effectively stopping the guy and the demon(?!). it could have been much better. if you have some time to kill and dont care whatsoever how horribly you spend it, well then this movie is for you. for the rest of you, don't bother, it isn't worth your time.
I would rate it 2/10