From vmartinez@panix.com Sun Mar 03 06:07:52 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!panix!vmartinez From: vmartinez@panix.com (Valeria Martínez) Newsgroups: comp.dsp Subject: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Mar03.060752.6668@panix.com> Date: Sun, 03 Mar 1996 06:07:52 GMT Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: WinVN 0.99.5 Lines: 11 I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS. 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). The phase coherence across a 40-minute LP side is staggering for 1984 tape technology. -- Valeria Martínez | vmartinez@panix.com PGP Key fingerprint: 3E7A E9D0 5E88 11BF "Keep the channels open." From brobertson@u-tokyo.ac.jp Sun Mar 03 12:52:52 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!u-tokyo!brobertson From: brobertson@u-tokyo.ac.jp (Bill Robertson) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Mar03.125252.4606@u-tokyo.ac.jp> Date: Sun, 03 Mar 1996 12:52:52 GMT References: <1996Mar03.060752.6668@panix.com> Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: Netscape 1.1N Lines: 12 In article <1996Mar03.060752.6668@panix.com>, vmartinez@panix.com (Valeria Martínez) writes: > I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS. > Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. Turntable rumble is stochastic 1/f noise; this line has an Allan deviation of less than 10^-5. It was generated by a quartz crystal clock. Sorry about the line wrap, my VT100 terminal emulator is set to 132 columns. -- Bill Robertson *PLONK* filter active for trolls. Commodore Amiga 500 (1MB OCS) - NetBSD 1.0 From mfischer@inria.fr Mon Mar 04 08:49:52 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!inria!mfischer From: mfischer@inria.fr (Mikhail Fischer) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Mar04.084952.5855@inria.fr> Date: Mon, 04 Mar 1996 08:49:52 GMT References: <1996Mar03.060752.6668@panix.com> Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: Netscape 1.1N Lines: 11 In article <1996Mar03.060752.6668@panix.com>, vmartinez@panix.com (Valeria Martínez) writes: > I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS. 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. Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- Mikhail Fischer *PLONK* filter active for trolls. Acorn RiscPC 600 - NetBSD 1.0 From dmoreno@cmu.edu Wed Mar 06 07:07:52 1996 Path: ashpoly!cascade!brgate!saturno!cmu!dmoreno From: dmoreno@cmu.edu (Dong-hyun Moreno) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Mar06.070752.8107@cmu.edu> Date: Wed, 06 Mar 1996 07:07:52 GMT References: <1996Mar03.060752.6668@panix.com> <1996Mar04.084952.5855@inria.fr> Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1996Mar04.084952.5855@inria.fr>, mfischer@inria.fr (Mikhail Fischer) 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. If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Dong-hyun Moreno Opinions expressed are solely my own and not those of Carnegie Mellon University School of CS. ------------------------------------------------------------ From rito@pipeline.com Thu Mar 07 11:27:52 1996 Path: ashpoly!cascade!bigsur!pipeline!rito From: rito@pipeline.com (Raj Ito) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Mar07.112752.1138@pipeline.com> Date: Thu, 07 Mar 1996 11:27:52 GMT References: <1996Mar03.060752.6668@panix.com> <1996Mar04.084952.5855@inria.fr> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Mar04.084952.5855@inria.fr>, mfischer@inria.fr (Mikhail Fischer) 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. 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. -- === Raj Ito === Dept of Electrical Engineering, The Pipeline Internet Network "There are 14 nodes and only 10 countries. Count again."