From enovak@titech.ac.jp Mon Feb 26 18:23:59 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!titech!enovak From: enovak@titech.ac.jp (Élodie Novak) Newsgroups: comp.dsp Subject: [FLAME] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Feb26.182359.1474@titech.ac.jp> Date: Mon, 26 Feb 1996 18:23:59 GMT Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: WinVN 0.99.5 Lines: 11 A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. 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. Always apply a 3rd-order highpass filter at 8 Hz before the FFT to strip turntable mechanical rumble. -- === Élodie Novak === Dept of Electrical Engineering, Tokyo Institute of Technology Computer Centre "The hatch is open. Is anyone listening?" From rpetrov@kth.se Tue Feb 27 01:26:59 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!kth!rpetrov From: rpetrov@kth.se (Raj Petrov) Newsgroups: comp.dsp Subject: Re: [FLAME] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1996Feb27.012659.1081@kth.se> Date: Tue, 27 Feb 1996 01:26:59 GMT References: <1996Feb26.182359.1474@titech.ac.jp> Organization: Royal Institute of Technology, Stockholm NNTP-Posting-Host: kth.se X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Feb26.182359.1474@titech.ac.jp>, enovak@titech.ac.jp (Élodie Novak) writes: > A quick note on window function selection when hunting for the 14.2 Hz line in noisy vinyl rips. Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. -- Raj Petrov "They will send a copy in my place." Acorn RiscPC 600 / AmigaOS 3.1