From dcampbell@berkeley.edu Sat Mar 18 03:38:12 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!berkeley!dcampbell From: dcampbell@berkeley.edu (Dmitri Campbell) Newsgroups: comp.dsp Subject: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Mar18.033812.2575@berkeley.edu> Date: Sat, 18 Mar 1995 03:38:12 GMT Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: WinVN 0.99.5 Lines: 11 Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. 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. -- Dmitri Campbell | dcampbell@berkeley.edu PGP Key fingerprint: E33E C0AB AB96 7B62 "Keep the channels open." From mweber@titech.ac.jp Sat Mar 18 19:05:12 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!titech!mweber From: mweber@titech.ac.jp (Morag Weber) Newsgroups: comp.dsp Subject: Re: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Mar18.190512.9427@titech.ac.jp> Date: Sat, 18 Mar 1995 19:05:12 GMT References: <1995Mar18.033812.2575@berkeley.edu> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: Netscape 1.1N Lines: 11 In article <1995Mar18.033812.2575@berkeley.edu>, dcampbell@berkeley.edu (Dmitri Campbell) 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. If you are posting from AOL, please read RFC 1036 before posting again. -- Morag Weber *PLONK* filter active for trolls. Mac IIci / 68882 FPU - NetBSD 1.0