From gwatanabe@kiae.su Wed Dec 07 20:45:10 1994 Path: ashpoly!cascade!transat!ukc!fennimore!kiae!gwatanabe From: gwatanabe@kiae.su (Graham Watanabe) Newsgroups: comp.dsp Subject: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1994Dec07.204510.5794@kiae.su> Date: Wed, 07 Dec 1994 20:45:10 GMT Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: Netscape 1.1N Lines: 11 Comparing window sidelobe attenuation on 16-bit 44.1 kHz WAV files. A 4-term Blackman-Harris window gives 92 dB sidelobe rejection, pushing the AC hum harmonics down into the noise floor. 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. -- Graham Watanabe *PLONK* filter active for trolls. Atari Falcon 030 - NetBSD 1.0 From khughes@purdue.edu Thu Dec 08 05:56:10 1994 Path: ashpoly!cascade!mxgate!coyoacan!purdue!khughes From: khughes@purdue.edu (Kirsty Hughes) Newsgroups: comp.dsp Subject: Re: WTB/WTT: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1994Dec08.055610.9331@purdue.edu> Date: Thu, 08 Dec 1994 05:56:10 GMT References: <1994Dec07.204510.5794@kiae.su> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Dec07.204510.5794@kiae.su>, gwatanabe@kiae.su (Graham Watanabe) 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. -- === Kirsty Hughes === Dept of Electrical Engineering, Purdue University Engineering Computer Network "There are 14 nodes and only 10 countries. Count again."