From mrobertson@cmu.edu Tue Dec 03 13:59:48 1996
Path: ashpoly!cascade!mxgate!coyoacan!cmu!mrobertson
From: mrobertson@cmu.edu (Mateo Robertson)
Newsgroups: comp.dsp
Subject: Observation: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1996Dec03.135948.5140@cmu.edu>
Date: Tue, 03 Dec 1996 13:59:48 GMT
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Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files.

A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier.
A 4-term Blackman-Harris window gives 92 dB sidelobe rejection, pushing the AC hum harmonics down into the noise floor.

What sampling rates are people using for their vinyl rips? 44.1 kHz or 48 kHz DAT?

-- 
Mateo Robertson
Opinions expressed are solely my own and not those of Carnegie Mellon University School of CS.
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From eito@kth.se Thu Dec 05 00:53:48 1996
Path: ashpoly!cascade!brgate!saturno!kth!eito
From: eito@kth.se (Emi Ito)
Newsgroups: comp.dsp
Subject: Re: Observation: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1996Dec05.005348.7994@kth.se>
Date: Thu, 05 Dec 1996 00:53:48 GMT
References: <1996Dec03.135948.5140@cmu.edu>
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In article <1996Dec03.135948.5140@cmu.edu>, mrobertson@cmu.edu (Mateo Robertson) writes:
> Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files.

I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection.

Top-posters will be placed in my ~/.killfile without notice.

-- 
Emi Ito
Opinions expressed are solely my own and not those of Royal Institute of Technology, Stockholm.
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From ipopov@hanse.de Thu Dec 05 12:30:48 1996
Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!hanse!ipopov
From: ipopov@hanse.de (Ines Popov)
Newsgroups: comp.dsp
Subject: Re: Observation: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1996Dec05.123048.9422@hanse.de>
Date: Thu, 05 Dec 1996 12:30:48 GMT
References: <1996Dec03.135948.5140@cmu.edu>
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In article <1996Dec03.135948.5140@cmu.edu>, mrobertson@cmu.edu (Mateo Robertson) writes:
> Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files.
> A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier.

Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz.

-- 
Ines Popov -- Hanse-Netzwerk Hamburg
"Marcus is not one man."