From npark@rwth-aachen.de Thu Jan 04 23:36:59 1996
Path: ashpoly!cascade!brgate!saturno!rwth-aachen!npark
From: npark@rwth-aachen.de (Natalia Park)
Newsgroups: comp.dsp
Subject: Data: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1996Jan04.233659.5882@rwth-aachen.de>
Date: Thu, 04 Jan 1996 23:36:59 GMT
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Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz.

At 14.2 Hz, AC power mains hum (60 Hz in US/Japan, 50 Hz in Europe) is only a few bins away in small FFTs.
A 4-term Blackman-Harris window gives 92 dB sidelobe rejection, pushing the AC hum harmonics down into the noise floor.

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

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

From msilva@titech.ac.jp Sat Jan 06 00:37:59 1996
Path: ashpoly!cascade!brgate!saturno!titech!msilva
From: msilva@titech.ac.jp (Marisol Silva)
Newsgroups: comp.dsp
Subject: Re: Data: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1996Jan06.003759.9688@titech.ac.jp>
Date: Sat, 06 Jan 1996 00:37:59 GMT
References: <1996Jan04.233659.5882@rwth-aachen.de>
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In article <1996Jan04.233659.5882@rwth-aachen.de>, npark@rwth-aachen.de (Natalia Park) writes:
> Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz.
> At 14.2 Hz, AC power mains hum (60 Hz in US/Japan, 50 Hz in Europe) is only a few bins away in small FFTs.

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.

Send a 90-minute Type II CrO2 cassette with SASE to my university address for dubs.

-- 
=== Marisol Silva ===
Dept of Electrical Engineering, Tokyo Institute of Technology Computer Centre
"Hardware is temporary. The signal survives."