naturerecordists
[Top] [All Lists]

Re: EIN values and bits

Subject: Re: EIN values and bits
From: "Avocet" madl74
Date: Tue Dec 4, 2012 9:36 am ((PST))
> Why isn't it better to aim for
> the maximum possible signal level initially in order to end up
> with the maximum s/n at the end?

John,

With analogue recording like tape, you always had a nagging recorder
noise level which you had to keep below the other noises in the
recording chain. Digital recording on the other hand gives you a very
wide dynamic range.

As Dan said with a 24 bit recording you have 21 bits to play with and
each bit represents 6dB, giving a huge range of 126dB. Thus if you
under record by 40dB, you still have a range of 86dB which is still
much better than your analogue stages before and after the recording
process.

As an example, the thermal noise of moving air molecules is around 0dB
sound pressure level and the threshold of ear damage is about 90dB
SPL, so under recording by 40dB still gives you a 126-90 = 36dB
leeway. The practical s/n limit is in the analogue stages before and
after the digital recording.

David

David Brinicombe
North Devon, UK
Cogito cogito ergo cogito sum - Ambrose Bierce







<Prev in Thread] Current Thread [Next in Thread>
Admin

The University of NSW School of Computer and Engineering takes no responsibility for the contents of this archive. It is purely a compilation of material sent by many people to the naturerecordists mailing list. It has not been checked for accuracy nor its content verified in any way. If you wish to get material removed from the archive or have other queries about the archive e-mail Andrew Taylor at this address: andrewt@cse.unsw.EDU.AU