Message-ID: <19084.200104111303@gemini>
From: "James Moritz" <j.r.moritz@herts.ac.uk>
Organization: University of Hertfordshire
To: rsgb_lf_group@blacksheep.org
Date: Wed, 11 Apr 2001 14:03:27 +0000
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Subject: Re: LF: WOLF - a question
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Dear Mike, LF Group,

When trying to recover a noisy signal with Wolf, it seems to be 
sufficient to set the audio level so that the louder bangs and cracks 
cause overload of the soundcard, but most of the time clipping is 
not occurring. I do this using Spectrum Lab's input monitor scope 
display, setting audio level so the normally green trace blinks red 
on the noise peaks every few seconds. I have not used Cool Edit 
in anger, but looking in the help files indicates that the 0dB level is 
the overload point. There are also a couple of overload indicators 
just to the right of the 0dB marks; however, once "lit", these stay 
on, so are not very useful in this context. I think setting the audio 
level so that 0dB is reached only on noise peaks should be OK. 
Ignore very big peaks, so long as they only cause occasional 
overloads.

The audio level is not very critical - I think the figure quoted is 
signal should be between 20dB and 50dB down on overload level. 
If the signal is not audible with the noise level set as above, this 
condition will be satisfied. If the signal is audible, setting the signal 
level so it is about 20 - 30dB down on the overload level seems to 
work well.

Cheers, Jim Moritz
73 de M0BMU