I just did the test.
1) Taped silence for 2 min at +12db on the jb3.
2) Taped silence for 2 min at 0db on the jb3 and boosted by +12db in Cool Edit Pro.
I didn't hear any difference between the two. I couldn't hear any hard drive noise or beeping on either. The snow coming from my speakers from being up that loud enough to try to hear anything and the hard drive on my computer effectively covered any noise that was recorded by my jb3.
What I did notice was that the wavform of test 1 was higher than the waveform of the test 2.
I spoke into the mics at the beginning of the tests to indicate which test was which. The levels of my voice on the first one is higher. I spoke from pretty much the same spot.
I normalized a 30 sec sample from each clip to 0db. I could easily hear beeps every 5-10 sec or so in both clips. The beeps from both tests sounded about the same loudness to me.
My conclusion: I think that the beeping from the jb3 is the same in both tests. As long as you're not listening to dead air, I don't think the beeping is a problem.
Here is are links to mp3s of my two tests
There is a short intro saying which test is which.
At about 20 sec the levels are normalized to 0db until about 50 sec.
Then the levels drop back to the "unmolested" levels.
http://www.horaenterprises.com/mp3/test1.mp3http://www.horaenterprises.com/mp3/test2.mp3YMMV.