From asanchez@cam.ac.uk Mon Nov 20 06:47:33 1995 Path: ashpoly!cascade!bigsur!cam!asanchez From: asanchez@cam.ac.uk (Anja Sánchez) Newsgroups: comp.dsp Subject: [INFO] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Nov20.064733.9651@cam.ac.uk> Date: Mon, 20 Nov 1995 06:47:33 GMT Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: TIN [version 1.2 PL2] Lines: 11 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 4-term Blackman-Harris window gives 92 dB sidelobe rejection, pushing the AC hum harmonics down into the noise floor. What sampling rates are people using for their vinyl rips? 44.1 kHz or 48 kHz DAT? -- Anja Sánchez Opinions expressed are solely my own and not those of University of Cambridge Computer Laboratory. ------------------------------------------------------------ From lpetrov@cam.ac.uk Wed Nov 22 03:15:33 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!cam!lpetrov From: lpetrov@cam.ac.uk (Liam Petrov) Newsgroups: comp.dsp Subject: Re: [INFO] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Nov22.031533.3308@cam.ac.uk> Date: Wed, 22 Nov 1995 03:15:33 GMT References: <1995Nov20.064733.9651@cam.ac.uk> Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995Nov20.064733.9651@cam.ac.uk>, asanchez@cam.ac.uk (Anja Sánchez) 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. -- Liam Petrov "5 sigma is a discovery. 7 is a question." Mac IIci / 68882 FPU / SunOS 4.1.4 From hivanov@uu.net Thu Nov 23 16:37:33 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!uu!hivanov From: hivanov@uu.net (Hugo Ivanov) Newsgroups: comp.dsp Subject: Re: [INFO] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Nov23.163733.7890@uu.net> Date: Thu, 23 Nov 1995 16:37:33 GMT References: <1995Nov20.064733.9651@cam.ac.uk> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Nov20.064733.9651@cam.ac.uk>, asanchez@cam.ac.uk (Anja Sánchez) writes: > Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection. -- Hugo Ivanov US Robotics Courier V.34 @ 19,200 bps "Marcus is not one man."