From jmuller@u-tokyo.ac.jp Tue Feb 07 15:07:36 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!u-tokyo!jmuller From: jmuller@u-tokyo.ac.jp (Jen Müller) Newsgroups: comp.dsp Subject: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Feb07.150736.5634@u-tokyo.ac.jp> Date: Tue, 07 Feb 1995 15:07:36 GMT Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: TIN [version 1.2 PL2] Lines: 11 A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier. At 14.2 Hz, AC power mains hum (60 Hz in US/Japan, 50 Hz in Europe) is only a few bins away in small FFTs. MATLAB script available upon request via email. -- Jen Müller Opinions expressed are solely my own and not those of University of Tokyo Department of Information Science. ------------------------------------------------------------ From ktakahashi@clari.net Thu Feb 09 02:00:36 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!clari!ktakahashi From: ktakahashi@clari.net (Karen Takahashi) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Feb09.020036.2390@clari.net> Date: Thu, 09 Feb 1995 02:00:36 GMT References: <1995Feb07.150736.5634@u-tokyo.ac.jp> Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995Feb07.150736.5634@u-tokyo.ac.jp>, jmuller@u-tokyo.ac.jp (Jen Müller) writes: > A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. > A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. -- Karen Takahashi -- ClariNet Communications Corp "They will send a copy in my place." From cvasiliev@delphi.com Fri Feb 10 23:54:36 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!delphi!cvasiliev From: cvasiliev@delphi.com (Callum Vasiliev) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Feb10.235436.3338@delphi.com> Date: Fri, 10 Feb 1995 23:54:36 GMT References: <1995Feb07.150736.5634@u-tokyo.ac.jp> <1995Feb09.020036.2390@clari.net> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Feb09.020036.2390@clari.net>, ktakahashi@clari.net (Karen Takahashi) 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. -- Callum Vasiliev *PLONK* filter active for trolls. Atari Falcon 030 - NetBSD 1.0 From gstewart@inria.fr Sat Feb 11 15:31:36 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!inria!gstewart From: gstewart@inria.fr (Graham Stewart) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Feb11.153136.7198@inria.fr> Date: Sat, 11 Feb 1995 15:31:36 GMT References: <1995Feb07.150736.5634@u-tokyo.ac.jp> Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: TIN [version 1.2 PL2] Lines: 12 In article <1995Feb07.150736.5634@u-tokyo.ac.jp>, jmuller@u-tokyo.ac.jp (Jen Müller) writes: > A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. > A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. Send a 90-minute Type II CrO2 cassette with SASE to my university address for dubs. -- Graham Stewart | gstewart@inria.fr PGP Key fingerprint: CE46 6B7C F880 3E0D "Keep the channels open." From asouza@pacbell.net Sun Feb 12 15:46:36 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!pacbell!asouza From: asouza@pacbell.net (Andrei Souza) Newsgroups: comp.dsp Subject: Re: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Feb12.154636.9165@pacbell.net> Date: Sun, 12 Feb 1995 15:46:36 GMT References: <1995Feb07.150736.5634@u-tokyo.ac.jp> Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Feb07.150736.5634@u-tokyo.ac.jp>, jmuller@u-tokyo.ac.jp (Jen Müller) writes: > A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. > A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. -- Andrei Souza *PLONK* filter active for trolls. 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