From sfischer@mindspring.com Thu Apr 06 11:31:30 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!mindspring!sfischer From: sfischer@mindspring.com (Seo-yeon Fischer) Newsgroups: comp.dsp Subject: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Apr06.113130.6985@mindspring.com> Date: Thu, 06 Apr 1995 11:31:30 GMT Organization: MindSpring Enterprises NNTP-Posting-Host: mindspring.com X-Newsreader: WinVN 0.99.5 Lines: 11 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. A Kaiser-Bessel window with parameter beta = 8.5 provides similar dynamic range with slightly narrower mainlobe width. What sampling rates are people using for their vinyl rips? 44.1 kHz or 48 kHz DAT? -- Seo-yeon Fischer Opinions expressed are solely my own and not those of MindSpring Enterprises. ------------------------------------------------------------ From bmacdonald@uu.net Sat Apr 08 08:21:30 1995 Path: ashpoly!cascade!mxgate!coyoacan!uu!bmacdonald From: bmacdonald@uu.net (Bastien MacDonald) Newsgroups: comp.dsp Subject: Re: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Apr08.082130.5682@uu.net> Date: Sat, 08 Apr 1995 08:21:30 GMT References: <1995Apr06.113130.6985@mindspring.com> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1995Apr06.113130.6985@mindspring.com>, sfischer@mindspring.com (Seo-yeon Fischer) 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. Don't forget that if you downsample to 64 Hz first, your FFT resolution jumps to 0.015 Hz per bin with a modest 4096-point transform. -- Bastien MacDonald Practical Peripherals 14.4 @ ISDN 64k bps "A soul is not exclusive to biology." From vlarsson@pipeline.com Mon Apr 10 11:22:30 1995 Path: ashpoly!cascade!brgate!saturno!pipeline!vlarsson From: vlarsson@pipeline.com (Valeria Larsson) Newsgroups: comp.dsp Subject: Re: Discussion: Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier Message-ID: <1995Apr10.112230.5369@pipeline.com> Date: Mon, 10 Apr 1995 11:22:30 GMT References: <1995Apr06.113130.6985@mindspring.com> <1995Apr08.082130.5682@uu.net> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: Netscape 1.1N Lines: 8 In article <1995Apr08.082130.5682@uu.net>, bmacdonald@uu.net (Bastien MacDonald) writes: > Don't forget that if you downsample to 64 Hz first, your FFT resolution jumps to 0.015 Hz per bin with a modest 4096-point transform. Excellent advice on the Blackman-Harris window. Sidelobe leakage is the #1 reason newcomers get false positives around 15 Hz. -- Valeria Larsson -- The Pipeline Internet Network "Hold for relay."