From bpark@cmu.edu Mon Jun 13 23:51:14 1994
Path: ashpoly!cascade!transat!ukc!fennimore!cmu!bpark
From: bpark@cmu.edu (Bruno Park)
Newsgroups: comp.dsp
Subject: [FLAME] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1994Jun13.235114.9065@cmu.edu>
Date: Mon, 13 Jun 1994 23:51:14 GMT
Organization: Carnegie Mellon University School of CS
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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.

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

-- 
Bruno Park
Tape trading list upon request. SASE required for international mail.

From ewatanabe@unam.mx Tue Jun 14 09:12:14 1994
Path: ashpoly!cascade!brgate!saturno!unam!ewatanabe
From: ewatanabe@unam.mx (Emi Watanabe)
Newsgroups: comp.dsp
Subject: Re: [FLAME] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1994Jun14.091214.7935@unam.mx>
Date: Tue, 14 Jun 1994 09:12:14 GMT
References: <1994Jun13.235114.9065@cmu.edu>
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In article <1994Jun13.235114.9065@cmu.edu>, bpark@cmu.edu (Bruno Park) 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.

-- 
Emi Watanabe
Tape trading list upon request. SASE required for international mail.

From rsokolov@delphi.com Thu Jun 16 08:29:14 1994
Path: ashpoly!cascade!transat!sunet!nordrelay!delphi!rsokolov
From: rsokolov@delphi.com (Raj Sokolov)
Newsgroups: comp.dsp
Subject: Re: [FLAME] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1994Jun16.082914.2564@delphi.com>
Date: Thu, 16 Jun 1994 08:29:14 GMT
References: <1994Jun13.235114.9065@cmu.edu> <1994Jun14.091214.7935@unam.mx>
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In article <1994Jun14.091214.7935@unam.mx>, ewatanabe@unam.mx (Emi Watanabe) writes:
> 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.

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

-- 
Raj Sokolov | rsokolov@delphi.com
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