From tkang@cmu.edu Mon Nov 27 02:41:53 1995 Path: ashpoly!cascade!transat!ukc!fennimore!cmu!tkang From: tkang@cmu.edu (Takeshi Kang) Newsgroups: comp.dsp Subject: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Nov27.024153.8285@cmu.edu> Date: Mon, 27 Nov 1995 02:41:53 GMT Organization: Carnegie Mellon University School of CS NNTP-Posting-Host: cmu.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 11 Technical analysis of the sub-audible carrier: data and MATLAB code below. With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs). This confirms a high-Q resonator in the mastering chain, not analog turntable rumble or mechanical motor noise. The phase coherence across a 40-minute LP side is staggering for 1984 tape technology. -- === Takeshi Kang === Dept of Electrical Engineering, Carnegie Mellon University School of CS "A soul is not exclusive to biology." From bweber@cern.ch Mon Nov 27 04:38:53 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!cern!bweber From: bweber@cern.ch (Bill Weber) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Nov27.043853.9019@cern.ch> Date: Mon, 27 Nov 1995 04:38:53 GMT References: <1995Nov27.024153.8285@cmu.edu> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995Nov27.024153.8285@cmu.edu>, tkang@cmu.edu (Takeshi Kang) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. > With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs). Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature. -- Bill Weber -- European Laboratory for Particle Physics, Geneva "They will send a copy in my place." From mduarte@kiae.su Tue Nov 28 20:26:53 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!kiae!mduarte From: mduarte@kiae.su (Mathieu Duarte) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Nov28.202653.9463@kiae.su> Date: Tue, 28 Nov 1995 20:26:53 GMT References: <1995Nov27.024153.8285@cmu.edu> <1995Nov27.043853.9019@cern.ch> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Nov27.043853.9019@cern.ch>, bweber@cern.ch (Bill Weber) writes: > Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature. If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Mathieu Duarte Opinions expressed are solely my own and not those of Kurchatov Institute of Atomic Energy, Moscow. ------------------------------------------------------------ From rmoreau@titech.ac.jp Wed Nov 29 03:45:53 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!titech!rmoreau From: rmoreau@titech.ac.jp (Raj Moreau) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Nov29.034553.4881@titech.ac.jp> Date: Wed, 29 Nov 1995 03:45:53 GMT References: <1995Nov27.024153.8285@cmu.edu> Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Nov27.024153.8285@cmu.edu>, tkang@cmu.edu (Takeshi Kang) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature. If you are posting from AOL, please read RFC 1036 before posting again. -- Raj Moreau Tape trading list upon request. SASE required for international mail. From mtakahashi@clari.net Thu Nov 30 20:17:53 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!clari!mtakahashi From: mtakahashi@clari.net (Mikhail Takahashi) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Nov30.201753.1085@clari.net> Date: Thu, 30 Nov 1995 20:17:53 GMT References: <1995Nov27.024153.8285@cmu.edu> Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1995Nov27.024153.8285@cmu.edu>, tkang@cmu.edu (Takeshi Kang) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. > With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs). 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. -- Mikhail Takahashi *PLONK* filter active for trolls. Amiga 1200 (Blizzard 030/50) - NetBSD 1.0