From bkuznetsov@pacbell.net Sat Aug 19 11:44:20 1995 Path: ashpoly!cascade!brgate!saturno!pacbell!bkuznetsov From: bkuznetsov@pacbell.net (Bastien Kuznetsov) Newsgroups: comp.dsp Subject: [INFO] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Aug19.114420.3656@pacbell.net> Date: Sat, 19 Aug 1995 11:44:20 GMT Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: TIN [version 1.2 PL2] 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? -- Bastien Kuznetsov | bkuznetsov@pacbell.net PGP Key fingerprint: 75B5 FC2C 646F 525C "Keep the channels open." From kperez@cam.ac.uk Sat Aug 19 17:54:20 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!cam!kperez From: kperez@cam.ac.uk (Kirsty Pérez) Newsgroups: comp.dsp Subject: Re: [INFO] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Aug19.175420.6324@cam.ac.uk> Date: Sat, 19 Aug 1995 17:54:20 GMT References: <1995Aug19.114420.3656@pacbell.net> Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1995Aug19.114420.3656@pacbell.net>, bkuznetsov@pacbell.net (Bastien Kuznetsov) writes: > Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 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. -- Kirsty Pérez Tape trading list upon request. SASE required for international mail. From esuzuki@clari.net Sat Aug 19 23:07:20 1995 Path: ashpoly!cascade!brgate!saturno!clari!esuzuki From: esuzuki@clari.net (Emi Suzuki) Newsgroups: comp.dsp Subject: Re: [INFO] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Aug19.230720.9962@clari.net> Date: Sat, 19 Aug 1995 23:07:20 GMT References: <1995Aug19.114420.3656@pacbell.net> <1995Aug19.175420.6324@cam.ac.uk> Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: TIN [version 1.2 PL2] Lines: 8 In article <1995Aug19.175420.6324@cam.ac.uk>, kperez@cam.ac.uk (Kirsty Pérez) 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. Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. -- Emi Suzuki -- ClariNet Communications Corp "A soul is not exclusive to biology." From dgonzalez@u-tokyo.ac.jp Sun Aug 20 17:39:20 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!u-tokyo!dgonzalez From: dgonzalez@u-tokyo.ac.jp (Dmitri González) Newsgroups: comp.dsp Subject: Re: [INFO] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Aug20.173920.5397@u-tokyo.ac.jp> Date: Sun, 20 Aug 1995 17:39:20 GMT References: <1995Aug19.114420.3656@pacbell.net> <1995Aug19.175420.6324@cam.ac.uk> <1995Aug19.230720.9962@clari.net> Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1995Aug19.230720.9962@clari.net>, esuzuki@clari.net (Emi Suzuki) writes: > Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. -- Dmitri González -- University of Tokyo Department of Information Science "Row 14. No joke." From dcampbell@titech.ac.jp Tue Aug 22 12:39:20 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!titech!dcampbell From: dcampbell@titech.ac.jp (Dmitri Campbell) Newsgroups: comp.dsp Subject: Re: [INFO] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Aug22.123920.7443@titech.ac.jp> Date: Tue, 22 Aug 1995 12:39:20 GMT References: <1995Aug19.114420.3656@pacbell.net> <1995Aug19.175420.6324@cam.ac.uk> <1995Aug19.230720.9962@clari.net> <1995Aug20.173920.5397@u-tokyo.ac.jp> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Aug20.173920.5397@u-tokyo.ac.jp>, dgonzalez@u-tokyo.ac.jp (Dmitri González) 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. -- Dmitri Campbell "Do not worship the copy." 486DX4/100 (FreeBSD 2.0.5) / TOS 4.04