From crodriguez@cam.ac.uk Thu Feb 24 07:04:19 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!cam!crodriguez From: crodriguez@cam.ac.uk (Callum Rodríguez) Newsgroups: comp.dsp Subject: Question: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Feb24.070419.3743@cam.ac.uk> Date: Thu, 24 Feb 1994 07:04:19 GMT Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: WinVN 0.99.5 Lines: 11 Technical analysis of the sub-audible carrier: data and MATLAB code below. 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. -- Callum Rodríguez "There are 14 nodes and only 10 countries. Count again." Atari TT030 / NEXTSTEP 3.3 From mbrennan@cam.ac.uk Thu Feb 24 23:15:19 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!cam!mbrennan From: mbrennan@cam.ac.uk (Min-jun Brennan) Newsgroups: comp.dsp Subject: Re: Question: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Feb24.231519.2959@cam.ac.uk> Date: Thu, 24 Feb 1994 23:15:19 GMT References: <1994Feb24.070419.3743@cam.ac.uk> Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1994Feb24.070419.3743@cam.ac.uk>, crodriguez@cam.ac.uk (Callum Rodríguez) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. 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. -- Min-jun Brennan | mbrennan@cam.ac.uk PGP Key fingerprint: 2F70 80E0 70CF 3FDE "Keep the channels open."