Oops...Black holes in a studio ?

Hi I went to my friend's room which is planned to be a home mixing room in the future...as we was running some tests, we placed the speakers in several positions and we was playing some sine frequency's to figure out which is the best position to start with the setup is not requiring any insulation just some frequency control and shaping (he's away from people and noise.....really away) anyway i was going to the rest room when my friend was walking thru the room to figure out the most annoying corners and the most good spots for each freq we test (honestly i'm not really sure about this process but that's what i did back in time for my home studio 3-4 y ago that's it :roll: ) 200Hz sine was playing continuously, and suddenly i felt that the sound went off for a fraction (like a fast mute un-mute) forget about the WC now i stepped back the same effect again (this is the first time i've experienced this ) i was aligning my head in this spot moving it from left to right, clockwise an so on "it was matter of few millimeters" in a specific point the bass sound will go and i can listen to the props vibration in the room window desk rows it's like if i canceled the sine sound without taking out the room effect caused by the vibration i belive that in un-treated room the sound specially bass freqs will vary from a place to other but is it possible to go so close to zero in a specific point I've tried this with these freqs 2000Hz = the sound vary the amplitude 800Hz = couldn't find the spot 600Hz = couldn't 200Hz =found Can somebody explain this thing why the black hole Sorry for my english thnx

how's yer current acoustics set up in that room? any pix/drawings/ more info?

no treatment is actually installed a normal rectangular room i want to know what is this phenomena .... why this happen in general

ps-2205-ycho wrote:

Can somebody explain this thing why the black hole

Peaks and nulls are caused by acoustic interference. Peaks are generally only a few dB, but nulls can be nearly infinitely deep. See the first section of this article: http://www.realtraps.com/facts.htm There's also a video that shows this. Find Non-Modal Peaks and Nulls on this page: http://www.realtraps.com/videos.htm The Comb Filtering video also discusses this phenomenon. --Ethan