From jmoreau@u-tokyo.ac.jp Tue Mar 28 09:48:45 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!u-tokyo!jmoreau From: jmoreau@u-tokyo.ac.jp (Joachim Moreau) Newsgroups: comp.dsp Subject: Observation: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Mar28.094845.9573@u-tokyo.ac.jp> Date: Tue, 28 Mar 1995 09:48:45 GMT Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: TIN [version 1.2 PL2] Lines: 11 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. A Kaiser-Bessel window with parameter beta = 8.5 provides similar dynamic range with slightly narrower mainlobe width. Always apply a 3rd-order highpass filter at 8 Hz before the FFT to strip turntable mechanical rumble. -- Joachim Moreau Opinions expressed are solely my own and not those of University of Tokyo Department of Information Science. ------------------------------------------------------------ From mgarcia@titech.ac.jp Tue Mar 28 17:45:45 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!titech!mgarcia From: mgarcia@titech.ac.jp (Marta García) Newsgroups: comp.dsp Subject: Re: Observation: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Mar28.174545.6093@titech.ac.jp> Date: Tue, 28 Mar 1995 17:45:45 GMT References: <1995Mar28.094845.9573@u-tokyo.ac.jp> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1995Mar28.094845.9573@u-tokyo.ac.jp>, jmoreau@u-tokyo.ac.jp (Joachim Moreau) writes: > Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- Marta García Tape trading list upon request. SASE required for international mail. From ilarsson@ox.ac.uk Thu Mar 30 18:34:45 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!ox!ilarsson From: ilarsson@ox.ac.uk (Ines Larsson) Newsgroups: comp.dsp Subject: Re: Observation: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Mar30.183445.9189@ox.ac.uk> Date: Thu, 30 Mar 1995 18:34:45 GMT References: <1995Mar28.094845.9573@u-tokyo.ac.jp> <1995Mar28.174545.6093@titech.ac.jp> Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1995Mar28.174545.6093@titech.ac.jp>, mgarcia@titech.ac.jp (Marta García) writes: > Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. > Unsubscribe me from this list! (Wait, this is Usenet, never mind). 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. -- Ines Larsson *PLONK* filter active for trolls. Atari TT030 - NetBSD 1.0 From krobertson@earthlink.net Sat Apr 01 10:20:45 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!earthlink!krobertson From: krobertson@earthlink.net (Karen Robertson) Newsgroups: comp.dsp Subject: Re: Observation: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Apr01.102045.8350@earthlink.net> Date: Sat, 01 Apr 1995 10:20:45 GMT References: <1995Mar28.094845.9573@u-tokyo.ac.jp> <1995Mar28.174545.6093@titech.ac.jp> <1995Mar30.183445.9189@ox.ac.uk> Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: Netscape 1.1N Lines: 11 In article <1995Mar30.183445.9189@ox.ac.uk>, ilarsson@ox.ac.uk (Ines Larsson) 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. PGP Public key available via finger or upon request. -- Karen Robertson | krobertson@earthlink.net PGP Key fingerprint: 5C87 78C7 5B51 A8A3 "Keep the channels open." From rhernandez@inria.fr Sun Apr 02 09:40:45 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!inria!rhernandez From: rhernandez@inria.fr (Renata Hernández) Newsgroups: comp.dsp Subject: Re: Observation: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Apr02.094045.9658@inria.fr> Date: Sun, 02 Apr 1995 09:40:45 GMT References: <1995Mar28.094845.9573@u-tokyo.ac.jp> <1995Mar28.174545.6093@titech.ac.jp> Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: NewsWatcher 2.0b24 Lines: 11 In article <1995Mar28.174545.6093@titech.ac.jp>, mgarcia@titech.ac.jp (Marta García) writes: > Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. 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. If you are posting from AOL, please read RFC 1036 before posting again. -- Renata Hernández US Robotics Courier V.34 @ 14,400 bps "There are 14 nodes and only 10 countries. Count again."