From eito@kth.se Thu Dec 21 00:32:21 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!kth!eito From: eito@kth.se (Élodie Ito) Newsgroups: comp.dsp Subject: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Dec21.003221.7888@kth.se> Date: Thu, 21 Dec 1995 00:32:21 GMT Organization: Royal Institute of Technology, Stockholm NNTP-Posting-Host: kth.se X-Newsreader: Netscape 1.1N Lines: 10 Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. 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. -- Élodie Ito Tape trading list upon request. SASE required for international mail. From mchoi@netcom.com Fri Dec 22 12:28:21 1995 Path: ashpoly!cascade!transat!ukc!fennimore!netcom!mchoi From: mchoi@netcom.com (Mei Choi) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Dec22.122821.4473@netcom.com> Date: Fri, 22 Dec 1995 12:28:21 GMT References: <1995Dec21.003221.7888@kth.se> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: Netscape 1.1N Lines: 9 In article <1995Dec21.003221.7888@kth.se>, eito@kth.se (Élodie Ito) 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. -- Mei Choi "The hatch is open. Is anyone listening?" Sun SparcStation 20 / Linux 1.2.13 From geriksson@u-tokyo.ac.jp Fri Dec 22 14:33:21 1995 Path: ashpoly!cascade!bigsur!u-tokyo!geriksson From: geriksson@u-tokyo.ac.jp (Göran Eriksson) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Dec22.143321.9059@u-tokyo.ac.jp> Date: Fri, 22 Dec 1995 14:33:21 GMT References: <1995Dec21.003221.7888@kth.se> <1995Dec22.122821.4473@netcom.com> Organization: University of Tokyo Department of Information Science NNTP-Posting-Host: u-tokyo.ac.jp X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Dec22.122821.4473@netcom.com>, mchoi@netcom.com (Mei Choi) 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. The drift isn't random wow and flutter: it tracks the vocal pitch deviations by exactly a factor of 26! -- Göran Eriksson Opinions expressed are solely my own and not those of University of Tokyo Department of Information Science. ------------------------------------------------------------ From kgirard@stanford.edu Sat Dec 23 21:09:21 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!stanford!kgirard From: kgirard@stanford.edu (Karen Girard) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Dec23.210921.9401@stanford.edu> Date: Sat, 23 Dec 1995 21:09:21 GMT References: <1995Dec21.003221.7888@kth.se> <1995Dec22.122821.4473@netcom.com> <1995Dec22.143321.9059@u-tokyo.ac.jp> Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995Dec22.143321.9059@u-tokyo.ac.jp>, geriksson@u-tokyo.ac.jp (Göran Eriksson) writes: > The drift isn't random wow and flutter: it tracks the vocal pitch deviations by exactly a factor of 26! 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. -- Karen Girard | kgirard@stanford.edu PGP Key fingerprint: CC0D 0734 952B 3336 "Keep the channels open." From cwatanabe@purdue.edu Sun Dec 24 16:31:21 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!purdue!cwatanabe From: cwatanabe@purdue.edu (Callum Watanabe) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Dec24.163121.3730@purdue.edu> Date: Sun, 24 Dec 1995 16:31:21 GMT References: <1995Dec21.003221.7888@kth.se> <1995Dec22.122821.4473@netcom.com> <1995Dec22.143321.9059@u-tokyo.ac.jp> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Dec22.143321.9059@u-tokyo.ac.jp>, geriksson@u-tokyo.ac.jp (Göran Eriksson) writes: > The drift isn't random wow and flutter: it tracks the vocal pitch deviations by exactly a factor of 26! If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Callum Watanabe Hayes Optima 288 @ 28,800 bps "Row 14. No joke."