First off grab this quick sample from here:
http://neilyboy.mtco.com/doug/diginoise.mp3I am using a set of Panasonic WM-61A caps that I performed the 'linkwitz' mod (reversing the polarity, to get less distortion with higher spl) > home made battery box > home-made ipod line-in connector hack (
http://www.sparkfun.com/commerce/product_info.php?products_id=704) > ipod nano (rockboxed). Keep in mind im I just going for 'cheap' and 'tiny'.
My main goal (after I figure out if this diginoise can be corrected) is to rig up some 61a caps in a hat to a female 1/8" mini-plug which can all be worn without discomfort or looking to obvious. So I am then able to run a M/M 1/8" cable from the plug to a battery box in a pocket then out to the recorder. I do not want to get into the 'why'. Yes this would produce nothing worth sharing but its honestly just for 'giggles' although I am impressed with just how well the cheap little 61a's perform. Ok onto the recording and question itself.
This recording was done only as a test to see just how 'stealth' I could be on a sub $100 budget. This recording was doomed from the beginning as I was only asked to go to the show about 2 hours before it started and I lived an hour away. Then when we arrived all the seats were filled except the two seats stage left and below the speakers in the room. So this recording was done at butt-level as it was rigged up in a hat that I sat on the seat next to me. This had no chance at getting a decent pull but I wanted to try it out to see how it would work. See picture here to see my position in the room.
I was basically behind and to the right of the stage in the back corner of the room.
The reason I am posting this here is to find out just what is producing this 'diginoise' which is very annoying throught the recording. Do not mind the 'white noise' which is heard throught the entire recording (this was caused by me having to run the recorder at +25 gain as the venue was not what I expected it to be). It was a very 'comfy' venue which seated only about 40-60 people. The music was very quiet and hard for the caps to pickup.
The noise I am asking about starts around the 0:33 - 1:11 mark of this sample. It comes and goes throught the entire recording. I am just wondering if it was caused by something not being shielded properly or what. I am going to run some more tests on it at home tonight to see if running different mics / power supplies to the ipod produce the same noise and then go from there (as it may be an issue with the home-made, line-in dock connector). I was just curious to see if anyone has had similar experiences and heard something similar?
I figure I can narrow it down by eliminating things from the mic's to the bb to the connector but thought I would throw this out there to see if someone would know just what I should be looking at first.
Thanks for the read and if I need to provide any other info just ask.
Neil