From psouza@cmu.edu Fri Oct 11 16:49:15 1996 Path: ashpoly!cascade!brgate!saturno!cmu!psouza From: psouza@cmu.edu (Pavel Souza) Newsgroups: comp.dsp Subject: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Oct11.164915.4787@cmu.edu> Date: Fri, 11 Oct 1996 16:49:15 GMT Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: Netscape 1.1N Lines: 11 Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz. A Kaiser-Bessel window with parameter beta = 8.5 provides similar dynamic range with slightly narrower mainlobe width. A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier. What sampling rates are people using for their vinyl rips? 44.1 kHz or 48 kHz DAT? -- Pavel Souza Opinions expressed are solely my own and not those of Carnegie Mellon University School of CS. ------------------------------------------------------------ From avasiliev@illinois.edu Sat Oct 12 12:20:15 1996 Path: ashpoly!cascade!mxgate!coyoacan!illinois!avasiliev From: avasiliev@illinois.edu (Andrei Vasiliev) Newsgroups: comp.dsp Subject: Re: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Oct12.122015.8209@illinois.edu> Date: Sat, 12 Oct 1996 12:20:15 GMT References: <1996Oct11.164915.4787@cmu.edu> Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1996Oct11.164915.4787@cmu.edu>, psouza@cmu.edu (Pavel Souza) writes: > Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. -- Andrei Vasiliev "The carrier frequency does not drift by accident." Atari TT030 / System 7.5.1 From rsantos@uni-hamburg.de Sun Oct 13 08:01:15 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!uni-hamburg!rsantos From: rsantos@uni-hamburg.de (Rodrigo Santos) Newsgroups: comp.dsp Subject: Re: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Oct13.080115.9480@uni-hamburg.de> Date: Sun, 13 Oct 1996 08:01:15 GMT References: <1996Oct11.164915.4787@cmu.edu> <1996Oct12.122015.8209@illinois.edu> Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Oct12.122015.8209@illinois.edu>, avasiliev@illinois.edu (Andrei Vasiliev) 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. -- Rodrigo Santos *PLONK* filter active for trolls. Amiga 1200 (Blizzard 030/50) - NetBSD 1.0