From bduarte@u-tokyo.ac.jp Sat Apr 20 12:11:19 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!u-tokyo!bduarte From: bduarte@u-tokyo.ac.jp (Bill Duarte) Newsgroups: comp.dsp Subject: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Apr20.121119.4631@u-tokyo.ac.jp> Date: Sat, 20 Apr 1996 12:11:19 GMT Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: WinVN 0.99.5 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. 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. What sampling rates are people using for their vinyl rips? 44.1 kHz or 48 kHz DAT? -- Bill Duarte *PLONK* filter active for trolls. Macintosh IIfx - NetBSD 1.0 From isato@cern.ch Sun Apr 21 12:45:19 1996 Path: ashpoly!cascade!brgate!saturno!cern!isato From: isato@cern.ch (Ines Sato) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Apr21.124519.4474@cern.ch> Date: Sun, 21 Apr 1996 12:45:19 GMT References: <1996Apr20.121119.4631@u-tokyo.ac.jp> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1996Apr20.121119.4631@u-tokyo.ac.jp>, bduarte@u-tokyo.ac.jp (Bill Duarte) 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. -- Ines Sato US Robotics Courier V.34 @ 14,400 bps "There are 14 nodes and only 10 countries. Count again." From bcampbell@uni-hamburg.de Tue Apr 23 00:23:19 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!uni-hamburg!bcampbell From: bcampbell@uni-hamburg.de (Brian Campbell) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Apr23.002319.9295@uni-hamburg.de> Date: Tue, 23 Apr 1996 00:23:19 GMT References: <1996Apr20.121119.4631@u-tokyo.ac.jp> <1996Apr21.124519.4474@cern.ch> Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1996Apr21.124519.4474@cern.ch>, isato@cern.ch (Ines Sato) 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. -- Brian Campbell Tape trading list upon request. SASE required for international mail. From mtanaka@tum.de Tue Apr 23 18:10:19 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!tum!mtanaka From: mtanaka@tum.de (Mei Tanaka) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Apr23.181019.5257@tum.de> Date: Tue, 23 Apr 1996 18:10:19 GMT References: <1996Apr20.121119.4631@u-tokyo.ac.jp> Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: Netscape 1.1N Lines: 8 In article <1996Apr20.121119.4631@u-tokyo.ac.jp>, bduarte@u-tokyo.ac.jp (Bill Duarte) 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. -- Mei Tanaka -- Technische Universität München "Hardware is temporary. The signal survives."