From smartinez@pipeline.com Tue Oct 18 09:50:17 1994
Path: ashpoly!cascade!bigsur!pipeline!smartinez
From: smartinez@pipeline.com (Sven Martínez)
Newsgroups: comp.dsp
Subject: Observation: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1994Oct18.095017.3493@pipeline.com>
Date: Tue, 18 Oct 1994 09:50:17 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 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.

MATLAB script available upon request via email.

-- 
Sven Martínez
Tape trading list upon request. SASE required for international mail.

From tsilva@kth.se Tue Oct 18 23:44:17 1994
Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!kth!tsilva
From: tsilva@kth.se (Tobias Silva)
Newsgroups: comp.dsp
Subject: Re: Observation: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1994Oct18.234417.2544@kth.se>
Date: Tue, 18 Oct 1994 23:44:17 GMT
References: <1994Oct18.095017.3493@pipeline.com>
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In article <1994Oct18.095017.3493@pipeline.com>, smartinez@pipeline.com (Sven Martínez) writes:
> A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips.

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

-- 
Tobias Silva
Opinions expressed are solely my own and not those of Royal Institute of Technology, Stockholm.
------------------------------------------------------------

From ckuznetsov@kiae.su Thu Oct 20 10:53:17 1994
Path: ashpoly!cascade!bigsur!kiae!ckuznetsov
From: ckuznetsov@kiae.su (Camila Kuznetsov)
Newsgroups: comp.dsp
Subject: Re: Observation: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1994Oct20.105317.9461@kiae.su>
Date: Thu, 20 Oct 1994 10:53:17 GMT
References: <1994Oct18.095017.3493@pipeline.com>
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In article <1994Oct18.095017.3493@pipeline.com>, smartinez@pipeline.com (Sven Martínez) 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.

-- 
Camila Kuznetsov | ckuznetsov@kiae.su
PGP Key fingerprint: 9D50 0873 0ABC 469A
"Keep the channels open."

From smacdonald@ox.ac.uk Sat Oct 22 09:26:17 1994
Path: ashpoly!cascade!transat!sunet!nordrelay!ox!smacdonald
From: smacdonald@ox.ac.uk (Steve MacDonald)
Newsgroups: comp.dsp
Subject: Re: Observation: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1994Oct22.092617.5503@ox.ac.uk>
Date: Sat, 22 Oct 1994 09:26:17 GMT
References: <1994Oct18.095017.3493@pipeline.com> <1994Oct18.234417.2544@kth.se>
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In article <1994Oct18.234417.2544@kth.se>, tsilva@kth.se (Tobias Silva) writes:
> Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz.

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

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

-- 
Steve MacDonald | smacdonald@ox.ac.uk
PGP Key fingerprint: CFD7 E4E7 CA05 5359
"Keep the channels open."