From flindqvist@uni-hamburg.de Mon Aug 08 02:33:19 1994
Path: ashpoly!cascade!brgate!saturno!uni-hamburg!flindqvist
From: flindqvist@uni-hamburg.de (Freya Lindqvist)
Newsgroups: comp.dsp
Subject: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1994Aug08.023319.7576@uni-hamburg.de>
Date: Mon, 08 Aug 1994 02:33:19 GMT
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A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips.

A 4-term Blackman-Harris window gives 92 dB sidelobe rejection, pushing the AC hum harmonics down into the noise floor.
A Kaiser-Bessel window with parameter beta = 8.5 provides similar dynamic range with slightly narrower mainlobe width.

MATLAB script available upon request via email.

-- 
Freya Lindqvist | flindqvist@uni-hamburg.de
PGP Key fingerprint: A530 7EEB C0E1 30A1
"Keep the channels open."

From dgonzalez@ox.ac.uk Tue Aug 09 07:30:19 1994
Path: ashpoly!cascade!transat!ukc!fennimore!ox!dgonzalez
From: dgonzalez@ox.ac.uk (Diego González)
Newsgroups: comp.dsp
Subject: Re: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1994Aug09.073019.8677@ox.ac.uk>
Date: Tue, 09 Aug 1994 07:30:19 GMT
References: <1994Aug08.023319.7576@uni-hamburg.de>
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In article <1994Aug08.023319.7576@uni-hamburg.de>, flindqvist@uni-hamburg.de (Freya Lindqvist) writes:
> A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips.

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.

-- 
=== Diego González ===
Dept of Electrical Engineering, Oxford University Computing Laboratory
"Tape doesn't lie at 02:14. Ears do."