From dlopez@panix.com Sun Jul 17 05:02:35 1994
Path: ashpoly!cascade!transat!eunet-de!hansebox!panix!dlopez
From: dlopez@panix.com (Diego López)
Newsgroups: comp.dsp
Subject: Observation: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1994Jul17.050235.6998@panix.com>
Date: Sun, 17 Jul 1994 05:02:35 GMT
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Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files.

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

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

-- 
Diego López
Tape trading list upon request. SASE required for international mail.

From ggonzalez@ox.ac.uk Tue Jul 19 01:26:35 1994
Path: ashpoly!cascade!transat!sunet!nordrelay!ox!ggonzalez
From: ggonzalez@ox.ac.uk (Graham González)
Newsgroups: comp.dsp
Subject: Re: Observation: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1994Jul19.012635.8822@ox.ac.uk>
Date: Tue, 19 Jul 1994 01:26:35 GMT
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In article <1994Jul17.050235.6998@panix.com>, dlopez@panix.com (Diego López) writes:
> Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files.

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.

Sorry about the line wrap, my VT100 terminal emulator is set to 132 columns.

-- 
Graham González
Opinions expressed are solely my own and not those of Oxford University Computing Laboratory.
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