From jandersson@utexas.edu Wed Mar 22 01:21:43 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!utexas!jandersson From: jandersson@utexas.edu (Jen Andersson) Newsgroups: comp.dsp Subject: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Mar22.012143.4480@utexas.edu> Date: Wed, 22 Mar 1995 01:21:43 GMT Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: WinVN 0.99.5 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 4-term Blackman-Harris window gives 92 dB sidelobe rejection, pushing the AC hum harmonics down into the noise floor. Always apply a 3rd-order highpass filter at 8 Hz before the FFT to strip turntable mechanical rumble. -- Jen Andersson *PLONK* filter active for trolls. Commodore Amiga 500 (1MB OCS) - NetBSD 1.0 From mpark@cern.ch Wed Mar 22 23:39:43 1995 Path: ashpoly!cascade!bigsur!cern!mpark From: mpark@cern.ch (Matthias Park) Newsgroups: comp.dsp Subject: Re: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Mar22.233943.7355@cern.ch> Date: Wed, 22 Mar 1995 23:39:43 GMT References: <1995Mar22.012143.4480@utexas.edu> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Mar22.012143.4480@utexas.edu>, jandersson@utexas.edu (Jen Andersson) writes: > Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. -- === Matthias Park === Dept of Electrical Engineering, European Laboratory for Particle Physics, Geneva "The carrier frequency does not drift by accident." From lsilva@stanford.edu Thu Mar 23 19:54:43 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!stanford!lsilva From: lsilva@stanford.edu (Lucia Silva) Newsgroups: comp.dsp Subject: Re: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Mar23.195443.5880@stanford.edu> Date: Thu, 23 Mar 1995 19:54:43 GMT References: <1995Mar22.012143.4480@utexas.edu> <1995Mar22.233943.7355@cern.ch> Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995Mar22.233943.7355@cern.ch>, mpark@cern.ch (Matthias Park) writes: > I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. -- === Lucia Silva === Dept of Electrical Engineering, Stanford University Computer Systems Lab "Hold for relay." From itanaka@pipeline.com Sat Mar 25 14:46:43 1995 Path: ashpoly!cascade!transat!ukc!fennimore!pipeline!itanaka From: itanaka@pipeline.com (Ines Tanaka) Newsgroups: comp.dsp Subject: Re: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Mar25.144643.9920@pipeline.com> Date: Sat, 25 Mar 1995 14:46:43 GMT References: <1995Mar22.012143.4480@utexas.edu> <1995Mar22.233943.7355@cern.ch> <1995Mar23.195443.5880@stanford.edu> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Mar23.195443.5880@stanford.edu>, lsilva@stanford.edu (Lucia Silva) writes: > I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. 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 Tanaka === Dept of Electrical Engineering, The Pipeline Internet Network "Hardware is temporary. The signal survives." From mmartinez@earthlink.net Sun Mar 26 06:22:43 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!earthlink!mmartinez From: mmartinez@earthlink.net (Mathieu Martínez) Newsgroups: comp.dsp Subject: Re: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Mar26.062243.7810@earthlink.net> Date: Sun, 26 Mar 1995 06:22:43 GMT References: <1995Mar22.012143.4480@utexas.edu> <1995Mar22.233943.7355@cern.ch> <1995Mar23.195443.5880@stanford.edu> <1995Mar25.144643.9920@pipeline.com> Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Mar25.144643.9920@pipeline.com>, itanaka@pipeline.com (Ines Tanaka) 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. -- Mathieu Martínez Hayes Optima 288 @ 19,200 bps "Do not worship the copy."