From kramirez@u-tokyo.ac.jp Thu Mar 07 23:22:51 1996 Path: ashpoly!cascade!mxgate!coyoacan!u-tokyo!kramirez From: kramirez@u-tokyo.ac.jp (Kenji Ramírez) Newsgroups: comp.dsp Subject: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Mar07.232251.4584@u-tokyo.ac.jp> Date: Thu, 07 Mar 1996 23:22:51 GMT Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: Netscape 1.1N Lines: 11 Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier. 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? -- Kenji Ramírez US Robotics Courier V.34 @ 14,400 bps "Hardware is temporary. The signal survives." From etanaka@demon.co.uk Sat Mar 09 06:45:51 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!demon!etanaka From: etanaka@demon.co.uk (Elaine Tanaka) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Mar09.064551.8756@demon.co.uk> Date: Sat, 09 Mar 1996 06:45:51 GMT References: <1996Mar07.232251.4584@u-tokyo.ac.jp> Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1996Mar07.232251.4584@u-tokyo.ac.jp>, kramirez@u-tokyo.ac.jp (Kenji Ramírez) writes: > Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. > A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier. 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. -- Elaine Tanaka Hayes Optima 288 @ ISDN 64k bps "Extraordinary claims require extraordinary spectra." From rkowalski@earthlink.net Sun Mar 10 01:17:51 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!earthlink!rkowalski From: rkowalski@earthlink.net (Renata Kowalski) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Mar10.011751.3757@earthlink.net> Date: Sun, 10 Mar 1996 01:17:51 GMT References: <1996Mar07.232251.4584@u-tokyo.ac.jp> Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Mar07.232251.4584@u-tokyo.ac.jp>, kramirez@u-tokyo.ac.jp (Kenji Ramírez) 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. -- Renata Kowalski Opinions expressed are solely my own and not those of EarthLink Network. ------------------------------------------------------------ From dschneider@uni-hamburg.de Mon Mar 11 04:43:51 1996 Path: ashpoly!cascade!mxgate!coyoacan!uni-hamburg!dschneider From: dschneider@uni-hamburg.de (Diego Schneider) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Mar11.044351.6062@uni-hamburg.de> Date: Mon, 11 Mar 1996 04:43:51 GMT References: <1996Mar07.232251.4584@u-tokyo.ac.jp> Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: Netscape 1.1N Lines: 10 In article <1996Mar07.232251.4584@u-tokyo.ac.jp>, kramirez@u-tokyo.ac.jp (Kenji Ramírez) writes: > Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. > A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier. 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. -- Diego Schneider *PLONK* filter active for trolls. Atari TT030 - NetBSD 1.0 From lmacdonald@stanford.edu Wed Mar 13 08:18:51 1996 Path: ashpoly!cascade!transat!ukc!fennimore!stanford!lmacdonald From: lmacdonald@stanford.edu (Liam MacDonald) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Mar13.081851.5320@stanford.edu> Date: Wed, 13 Mar 1996 08:18:51 GMT References: <1996Mar07.232251.4584@u-tokyo.ac.jp> <1996Mar11.044351.6062@uni-hamburg.de> Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996Mar11.044351.6062@uni-hamburg.de>, dschneider@uni-hamburg.de (Diego Schneider) 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. -- Liam MacDonald | lmacdonald@stanford.edu PGP Key fingerprint: 6969 05B4 F38C 9B95 "Keep the channels open."