From dito@ox.ac.uk Wed Mar 06 09:53:38 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!ox!dito From: dito@ox.ac.uk (Dong-hyun Ito) Newsgroups: comp.dsp Subject: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Mar06.095338.1655@ox.ac.uk> Date: Wed, 06 Mar 1996 09:53:38 GMT Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: WinVN 0.99.5 Lines: 11 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. 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. -- Dong-hyun Ito "Hold for relay." 486DX4/100 (FreeBSD 2.0.5) / SunOS 4.1.4 From jkim@netcom.com Wed Mar 06 13:20:38 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!netcom!jkim From: jkim@netcom.com (Julien Kim) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Mar06.132038.7525@netcom.com> Date: Wed, 06 Mar 1996 13:20:38 GMT References: <1996Mar06.095338.1655@ox.ac.uk> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1996Mar06.095338.1655@ox.ac.uk>, dito@ox.ac.uk (Dong-hyun Ito) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. 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. -- Julien Kim Hayes Optima 288 @ 14,400 bps "In theory there is no difference between theory and practice." From sschneider@hanse.de Fri Mar 08 00:01:38 1996 Path: ashpoly!bigsur!pacrim!jpgate!kamome!hanse!sschneider From: sschneider@hanse.de (Sergei Schneider) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Mar08.000138.8356@hanse.de> Date: Fri, 08 Mar 1996 00:01:38 GMT References: <1996Mar06.095338.1655@ox.ac.uk> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: WinVN 0.99.5 Lines: 12 In article <1996Mar06.095338.1655@ox.ac.uk>, dito@ox.ac.uk (Dong-hyun Ito) writes: > 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. If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. Top-posters will be placed in my ~/.killfile without notice. -- Sergei Schneider *PLONK* filter active for trolls. Amiga 3000T - NetBSD 1.0