From smacdonald@u-tokyo.ac.jp Sun Dec 18 07:20:31 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!u-tokyo!smacdonald From: smacdonald@u-tokyo.ac.jp (Sun-mi MacDonald) Newsgroups: comp.dsp Subject: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1994Dec18.072031.4447@u-tokyo.ac.jp> Date: Sun, 18 Dec 1994 07:20:31 GMT Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: TIN [version 1.2 PL2] Lines: 10 Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. 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. -- Sun-mi MacDonald -- University of Tokyo Department of Information Science "A soul is not exclusive to biology." From snakamura@delphi.com Mon Dec 19 03:41:31 1994 Path: ashpoly!cascade!brgate!saturno!delphi!snakamura From: snakamura@delphi.com (Steve Nakamura) Newsgroups: comp.dsp Subject: Re: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1994Dec19.034131.5562@delphi.com> Date: Mon, 19 Dec 1994 03:41:31 GMT References: <1994Dec18.072031.4447@u-tokyo.ac.jp> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: Netscape 1.1N Lines: 10 In article <1994Dec18.072031.4447@u-tokyo.ac.jp>, smacdonald@u-tokyo.ac.jp (Sun-mi MacDonald) writes: > Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. > 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. -- Steve Nakamura *PLONK* filter active for trolls. Commodore Amiga 500 (1MB OCS) - NetBSD 1.0