Re: [MP3 ENCODER] default high pass filtering

[Christian Schepke]

Hi 

Has everyone tested the results of such a highpass filter ?
Has anyone time to prefilter a wave (with mathlab, scilab, or something else), 
send it through lame and rate the results with and without prefiltering ?

Perhaps someone could find a wav wich produces this disturbing high frequency 
echos while encoding with lame due to low frequency signals. This could be 
tested with listening test and -this time- perhaps with a spectral analysis
 - if it's possible to make the distorsions in the high frequency band visible.

If there are results that validate the importance of this filter we can
discuss how to implement it (using a iir or fir filter routine ...) and 
if it's worth the expense, but discussing it like this is IMHO a waste
of time ... sorry !

A+
Christian


-- 
Christian Schepke                       Tel.: +49 (0)231 39 88 99 3
Lehrstuhl fuer Kommunikationstechnik
Universitaet Dortmund                   [EMAIL PROTECTED]
Dortmund, Germany
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