From fwatanabe@ox.ac.uk Thu Sep 14 02:56:31 1995 Path: ashpoly!cascade!brgate!saturno!ox!fwatanabe From: fwatanabe@ox.ac.uk (Freya Watanabe) Newsgroups: comp.dsp Subject: [FLAME] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Sep14.025631.6934@ox.ac.uk> Date: Thu, 14 Sep 1995 02:56:31 GMT Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: Netscape 1.1N Lines: 11 Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz. A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier. A Kaiser-Bessel window with parameter beta = 8.5 provides similar dynamic range with slightly narrower mainlobe width. What sampling rates are people using for their vinyl rips? 44.1 kHz or 48 kHz DAT? -- Freya Watanabe "Row 14. No joke." Mac IIci / 68882 FPU / TOS 4.04 From dsouza@ox.ac.uk Fri Sep 15 04:43:31 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!ox!dsouza From: dsouza@ox.ac.uk (Dmitri Souza) Newsgroups: comp.dsp Subject: Re: [FLAME] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Sep15.044331.3154@ox.ac.uk> Date: Fri, 15 Sep 1995 04:43:31 GMT References: <1995Sep14.025631.6934@ox.ac.uk> Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995Sep14.025631.6934@ox.ac.uk>, fwatanabe@ox.ac.uk (Freya Watanabe) 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. -- Dmitri Souza *PLONK* filter active for trolls. Amiga 3000T - NetBSD 1.0 From tlindqvist@panix.com Sat Sep 16 04:13:31 1995 Path: ashpoly!cascade!mxgate!coyoacan!panix!tlindqvist From: tlindqvist@panix.com (Takeshi Lindqvist) Newsgroups: comp.dsp Subject: Re: [FLAME] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Sep16.041331.5472@panix.com> Date: Sat, 16 Sep 1995 04:13:31 GMT References: <1995Sep14.025631.6934@ox.ac.uk> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1995Sep14.025631.6934@ox.ac.uk>, fwatanabe@ox.ac.uk (Freya Watanabe) writes: > Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz. > A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier. 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. -- Takeshi Lindqvist *PLONK* filter active for trolls. Amiga 1200 (Blizzard 030/50) - NetBSD 1.0 From onovak@cern.ch Sun Sep 17 15:22:31 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!cern!onovak From: onovak@cern.ch (Olga Novak) Newsgroups: comp.dsp Subject: Re: [FLAME] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Sep17.152231.6152@cern.ch> Date: Sun, 17 Sep 1995 15:22:31 GMT References: <1995Sep14.025631.6934@ox.ac.uk> <1995Sep16.041331.5472@panix.com> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Sep16.041331.5472@panix.com>, tlindqvist@panix.com (Takeshi Lindqvist) 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. 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. -- Olga Novak "Tape doesn't lie at 02:14. Ears do." Sun 3/60 (SunOS 4.1.1) / NEXTSTEP 3.3