From aito@utexas.edu Fri Apr 14 16:23:47 1995
Path: ashpoly!cascade!transat!ukc!fennimore!utexas!aito
From: aito@utexas.edu (Anja Ito)
Newsgroups: comp.dsp
Subject: [SPECULATION] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1995Apr14.162347.7157@utexas.edu>
Date: Fri, 14 Apr 1995 16:23:47 GMT
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Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files.

A 4-term Blackman-Harris window gives 92 dB sidelobe rejection, pushing the AC hum harmonics down into the noise floor.
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.

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

-- 
Anja Ito
Opinions expressed are solely my own and not those of University of Texas at Austin.
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From fkang@pipeline.com Sat Apr 15 14:44:47 1995
Path: ashpoly!cascade!brgate!saturno!pipeline!fkang
From: fkang@pipeline.com (Freya Kang)
Newsgroups: comp.dsp
Subject: Re: [SPECULATION] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1995Apr15.144447.1951@pipeline.com>
Date: Sat, 15 Apr 1995 14:44:47 GMT
References: <1995Apr14.162347.7157@utexas.edu>
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In article <1995Apr14.162347.7157@utexas.edu>, aito@utexas.edu (Anja Ito) 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.

-- 
Freya Kang
Tape trading list upon request. SASE required for international mail.

From hsato@titech.ac.jp Sun Apr 16 11:57:47 1995
Path: ashpoly!cascade!transat!eunet-de!hansebox!titech!hsato
From: hsato@titech.ac.jp (Hana Sato)
Newsgroups: comp.dsp
Subject: Re: [SPECULATION] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1995Apr16.115747.6095@titech.ac.jp>
Date: Sun, 16 Apr 1995 11:57:47 GMT
References: <1995Apr14.162347.7157@utexas.edu> <1995Apr15.144447.1951@pipeline.com>
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In article <1995Apr15.144447.1951@pipeline.com>, fkang@pipeline.com (Freya Kang) 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.

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.

-- 
Hana Sato
Opinions expressed are solely my own and not those of Tokyo Institute of Technology Computer Centre.
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