> Can you briefly explain the process of differentiating system noise
> from mic noise.
John,
Briefly, by comparing mic hiss with a dummy input load, conventionally
Message: 150ohms.
Subject: If you haven't got one, buy a 150ohm resistor from Radio
Shack and shove it into XLR sockets 2 and 3.
With my MKH's there is a characteristic dip in the HF mic noise
profile which I can recognise on a power spectrum. I'm in a quiet
place and often hear mic hiss outdoors, but I confirmed this by piling
bedclothes on my mics and turning everything off in the house that
vibrates. (interestingly I still got a low level 50Hz mains hum
probably from the house wiring) I've got "calibrated ears" and 6 to 10
dBs swamps a similar signal. I now know by ear what the mic noise
level is and let this drown the mixer noise with the dummy input load
and fader settings.
I also record "native" with a Tascam DR-100 without a mixer where the
system noise is the Tascam XLR input stage. I've never managed to hear
quantisation noise from the digital stage which is going to be around
90dB below peak or lower.
You can't get away from mic noise, so if you drown other noises
(primarily hiss) with mic hiss, you can't do better at the lower
levels. This setting is about right for a normal speaking voice at 1
to 2 metres and is fine for my wildlife and only a close pheasant has
hit the limiter in the mixer.
David
David Brinicombe
North Devon, UK
Cogito cogito ergo cogito sum - Ambrose Bierce
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