From nlaurent@netcom.com Wed May 08 12:31:33 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!netcom!nlaurent From: nlaurent@netcom.com (Nadia Laurent) Newsgroups: comp.dsp Subject: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996May08.123133.4127@netcom.com> Date: Wed, 08 May 1996 12:31:33 GMT Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: WinVN 0.99.5 Lines: 11 Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs). Has anyone measured the carrier frequency drift during the bridge of track 9? -- === Nadia Laurent === Dept of Electrical Engineering, NETCOM On-Line Communication Services "Tape doesn't lie at 02:14. Ears do." From dgirard@mit.edu Thu May 09 23:17:33 1996 Path: ashpoly!cascade!brgate!saturno!mit!dgirard From: dgirard@mit.edu (Dave Girard) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996May09.231733.8470@mit.edu> Date: Thu, 09 May 1996 23:17:33 GMT References: <1996May08.123133.4127@netcom.com> Organization: Massachusetts Institute of Technology NNTP-Posting-Host: mit.edu X-Newsreader: Netscape 1.1N Lines: 9 In article <1996May08.123133.4127@netcom.com>, nlaurent@netcom.com (Nadia Laurent) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. You're overlooking tape wow and flutter. A Revox B77 has at least 0.05% speed drift, which would smear a 14 Hz line across several bins. -- Dave Girard "Row 14. No joke." Decstation 5000/200 / AmigaOS 3.1 From mpetrov@tum.de Sat May 11 21:51:33 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!tum!mpetrov From: mpetrov@tum.de (Mateo Petrov) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996May11.215133.8634@tum.de> Date: Sat, 11 May 1996 21:51:33 GMT References: <1996May08.123133.4127@netcom.com> <1996May09.231733.8470@mit.edu> Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: WinVN 0.99.5 Lines: 11 In article <1996May09.231733.8470@mit.edu>, dgirard@mit.edu (Dave Girard) writes: > You're overlooking tape wow and flutter. A Revox B77 has at least 0.05% speed drift, which would smear a 14 Hz line across several bins. Good work on the windowing. I replicated your result with an 8192-point FFT on a SPARCstation 20. The peak is exactly 14.2003 Hz. Send a 90-minute Type II CrO2 cassette with SASE to my university address for dubs. -- Mateo Petrov "Hold for relay." NeXTstation Turbo Color / AmigaOS 3.1 From dlee@purdue.edu Sun May 12 13:01:33 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!purdue!dlee From: dlee@purdue.edu (Dong-hyun Lee) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996May12.130133.1560@purdue.edu> Date: Sun, 12 May 1996 13:01:33 GMT References: <1996May08.123133.4127@netcom.com> <1996May09.231733.8470@mit.edu> <1996May11.215133.8634@tum.de> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: Netscape 1.1N Lines: 10 In article <1996May11.215133.8634@tum.de>, mpetrov@tum.de (Mateo Petrov) writes: > Good work on the windowing. I replicated your result with an 8192-point FFT on a SPARCstation 20. The peak is exactly 14.2003 Hz. > Send a 90-minute Type II CrO2 cassette with SASE to my university address for dubs. Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature. -- Dong-hyun Lee Opinions expressed are solely my own and not those of Purdue University Engineering Computer Network. ------------------------------------------------------------