From lmoreno@hanse.de Sun Jun 18 02:29:46 1995
Path: ashpoly!bigsur!pacrim!krgate!eunha!hanse!lmoreno
From: lmoreno@hanse.de (Liam Moreno)
Newsgroups: comp.dsp
Subject: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1995Jun18.022946.7360@hanse.de>
Date: Sun, 18 Jun 1995 02:29:46 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 Kaiser-Bessel window with parameter beta = 8.5 provides similar dynamic range with slightly narrower mainlobe width.

Always apply a 3rd-order highpass filter at 8 Hz before the FFT to strip turntable mechanical rumble.

-- 
Liam Moreno <lmoreno@hanse.de>
*PLONK* filter active for trolls.
486DX2/66 (Linux 1.2.13) - NetBSD 1.0

From asuzuki@stanford.edu Sun Jun 18 04:11:46 1995
Path: ashpoly!cascade!brgate!saturno!stanford!asuzuki
From: asuzuki@stanford.edu (Amy Suzuki)
Newsgroups: comp.dsp
Subject: Re: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1995Jun18.041146.9116@stanford.edu>
Date: Sun, 18 Jun 1995 04:11:46 GMT
References: <1995Jun18.022946.7360@hanse.de>
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In article <1995Jun18.022946.7360@hanse.de>, lmoreno@hanse.de (Liam Moreno) 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.

-- 
Amy Suzuki
Tape trading list upon request. SASE required for international mail.

From leriksson@kiae.su Mon Jun 19 06:05:46 1995
Path: ashpoly!bigsur!pacrim!krgate!eunha!kiae!leriksson
From: leriksson@kiae.su (Lisa Eriksson)
Newsgroups: comp.dsp
Subject: Re: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1995Jun19.060546.1347@kiae.su>
Date: Mon, 19 Jun 1995 06:05:46 GMT
References: <1995Jun18.022946.7360@hanse.de> <1995Jun18.041146.9116@stanford.edu>
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In article <1995Jun18.041146.9116@stanford.edu>, asuzuki@stanford.edu (Amy Suzuki) writes:
> I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection.

Don't forget that if you downsample to 64 Hz first, your FFT resolution jumps to 0.015 Hz per bin with a modest 4096-point transform.

-- 
=== Lisa Eriksson ===
Dept of Electrical Engineering, Kurchatov Institute of Atomic Energy, Moscow
"Tape doesn't lie at 02:14. Ears do."

From jlarsson@uni-hamburg.de Mon Jun 19 10:04:46 1995
Path: ashpoly!cascade!transat!sunet!nordrelay!uni-hamburg!jlarsson
From: jlarsson@uni-hamburg.de (Julien Larsson)
Newsgroups: comp.dsp
Subject: Re: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1995Jun19.100446.1886@uni-hamburg.de>
Date: Mon, 19 Jun 1995 10:04:46 GMT
References: <1995Jun18.022946.7360@hanse.de>
Organization: Universität Hamburg Fachbereich Informatik
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In article <1995Jun18.022946.7360@hanse.de>, lmoreno@hanse.de (Liam Moreno) 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.

-- 
Julien Larsson | jlarsson@uni-hamburg.de
PGP Key fingerprint: 7F2F 9C38 B10B F3CB
"Keep the channels open."