From fandersson@cern.ch Sat Mar 11 07:21:13 1995 Path: ashpoly!cascade!transat!ukc!fennimore!cern!fandersson From: fandersson@cern.ch (Fiona Andersson) Newsgroups: comp.dsp Subject: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Mar11.072113.6360@cern.ch> Date: Sat, 11 Mar 1995 07:21:13 GMT Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: TIN [version 1.2 PL2] Lines: 10 Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. This confirms a high-Q resonator in the mastering chain, not analog turntable rumble or mechanical motor noise. Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. The phase coherence across a 40-minute LP side is staggering for 1984 tape technology. -- Fiona Andersson Tape trading list upon request. SASE required for international mail. From glindqvist@earthlink.net Sun Mar 12 22:43:13 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!earthlink!glindqvist From: glindqvist@earthlink.net (Göran Lindqvist) Newsgroups: comp.dsp Subject: Re: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Mar12.224313.7721@earthlink.net> Date: Sun, 12 Mar 1995 22:43:13 GMT References: <1995Mar11.072113.6360@cern.ch> Organization: EarthLink Network NNTP-Posting-Host: earthlink.net X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1995Mar11.072113.6360@cern.ch>, fandersson@cern.ch (Fiona Andersson) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. > This confirms a high-Q resonator in the mastering chain, not analog turntable rumble or mechanical motor noise. 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. -- Göran Lindqvist | glindqvist@earthlink.net PGP Key fingerprint: 6C8C 8A20 503B 3E41 "Keep the channels open."