From fdubois@purdue.edu Wed Jan 18 05:02:17 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!purdue!fdubois From: fdubois@purdue.edu (Freya Dubois) Newsgroups: comp.dsp Subject: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Jan18.050217.7804@purdue.edu> Date: Wed, 18 Jan 1995 05:02:17 GMT Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu 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. -- Freya Dubois Opinions expressed are solely my own and not those of Purdue University Engineering Computer Network. ------------------------------------------------------------ From mtanaka@kth.se Fri Jan 20 04:06:17 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!kth!mtanaka From: mtanaka@kth.se (Mathieu Tanaka) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Jan20.040617.3765@kth.se> Date: Fri, 20 Jan 1995 04:06:17 GMT References: <1995Jan18.050217.7804@purdue.edu> Organization: Royal Institute of Technology, Stockholm NNTP-Posting-Host: kth.se X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Jan18.050217.7804@purdue.edu>, fdubois@purdue.edu (Freya Dubois) 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. -- Mathieu Tanaka *PLONK* filter active for trolls. 486DX4/100 (FreeBSD 2.0.5) - NetBSD 1.0 From mramirez@illinois.edu Fri Jan 20 21:41:17 1995 Path: ashpoly!cascade!brgate!saturno!illinois!mramirez From: mramirez@illinois.edu (Marta Ramírez) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Jan20.214117.1641@illinois.edu> Date: Fri, 20 Jan 1995 21:41:17 GMT References: <1995Jan18.050217.7804@purdue.edu> <1995Jan20.040617.3765@kth.se> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Jan20.040617.3765@kth.se>, mtanaka@kth.se (Mathieu Tanaka) 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. -- === Marta Ramírez === Dept of Electrical Engineering, University of Illinois Urbana-Champaign "Do not worship the copy." From mito@kiae.su Sun Jan 22 23:52:17 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!kiae!mito From: mito@kiae.su (Min-jun Ito) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Jan22.235217.1118@kiae.su> Date: Sun, 22 Jan 1995 23:52:17 GMT References: <1995Jan18.050217.7804@purdue.edu> <1995Jan20.040617.3765@kth.se> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Jan20.040617.3765@kth.se>, mtanaka@kth.se (Mathieu Tanaka) 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. If you are posting from AOL, please read RFC 1036 before posting again. -- Min-jun Ito Tape trading list upon request. SASE required for international mail.