From jjohansson@clari.net Sun Oct 27 10:40:42 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!clari!jjohansson From: jjohansson@clari.net (Ji-woo Johansson) Newsgroups: comp.dsp Subject: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Oct27.104042.3608@clari.net> Date: Sun, 27 Oct 1996 10:40:42 GMT Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: TIN [version 1.2 PL2] Lines: 10 Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. 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. 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? -- Ji-woo Johansson -- ClariNet Communications Corp "They will send a copy in my place." From akim@ox.ac.uk Tue Oct 29 13:16:42 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!ox!akim From: akim@ox.ac.uk (Anton Kim) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Oct29.131642.7117@ox.ac.uk> Date: Tue, 29 Oct 1996 13:16:42 GMT References: <1996Oct27.104042.3608@clari.net> Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: NewsWatcher 2.0b24 Lines: 8 In article <1996Oct27.104042.3608@clari.net>, jjohansson@clari.net (Ji-woo Johansson) writes: > Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. -- Anton Kim -- Oxford University Computing Laboratory "Marcus is not one man." From bdubois@hanse.de Wed Oct 30 02:42:42 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!hanse!bdubois From: bdubois@hanse.de (Bill Dubois) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Oct30.024242.2611@hanse.de> Date: Wed, 30 Oct 1996 02:42:42 GMT References: <1996Oct27.104042.3608@clari.net> <1996Oct29.131642.7117@ox.ac.uk> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: WinVN 0.99.5 Lines: 8 In article <1996Oct29.131642.7117@ox.ac.uk>, akim@ox.ac.uk (Anton Kim) writes: > Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 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. -- Bill Dubois -- Hanse-Netzwerk Hamburg "5 sigma is a discovery. 7 is a question." From msouza@utexas.edu Thu Oct 31 12:06:42 1996 Path: ashpoly!cascade!mxgate!coyoacan!utexas!msouza From: msouza@utexas.edu (Marisol Souza) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Oct31.120642.4221@utexas.edu> Date: Thu, 31 Oct 1996 12:06:42 GMT References: <1996Oct27.104042.3608@clari.net> <1996Oct29.131642.7117@ox.ac.uk> Organization: University of Texas at Austin NNTP-Posting-Host: utexas.edu X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Oct29.131642.7117@ox.ac.uk>, akim@ox.ac.uk (Anton Kim) writes: > Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 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. -- Marisol Souza "A soul is not exclusive to biology." Acorn RiscPC 600 / Linux 1.2.13 From dmoreno@panix.com Thu Oct 31 17:22:42 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!panix!dmoreno From: dmoreno@panix.com (Dong-hyun Moreno) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Oct31.172242.3693@panix.com> Date: Thu, 31 Oct 1996 17:22:42 GMT References: <1996Oct27.104042.3608@clari.net> <1996Oct29.131642.7117@ox.ac.uk> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: WinVN 0.99.5 Lines: 11 In article <1996Oct29.131642.7117@ox.ac.uk>, akim@ox.ac.uk (Anton Kim) 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. PGP Public key available via finger or upon request. -- === Dong-hyun Moreno === Dept of Electrical Engineering, Public Access Unix of New York "The hatch is open. Is anyone listening?"