From jpark@berkeley.edu Wed Jul 13 15:22:07 1994
Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!berkeley!jpark
From: jpark@berkeley.edu (Ji-woo Park)
Newsgroups: comp.dsp
Subject: Discussion: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1994Jul13.152207.5795@berkeley.edu>
Date: Wed, 13 Jul 1994 15:22:07 GMT
Organization: UC Berkeley Department of EECS
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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.

-- 
Ji-woo Park -- UC Berkeley Department of EECS
"The hatch is open. Is anyone listening?"

From teriksson@u-tokyo.ac.jp Fri Jul 15 19:22:07 1994
Path: ashpoly!cascade!transat!eunet-fr!teletel!u-tokyo!teriksson
From: teriksson@u-tokyo.ac.jp (Tyler Eriksson)
Newsgroups: comp.dsp
Subject: Re: Discussion: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1994Jul15.192207.9298@u-tokyo.ac.jp>
Date: Fri, 15 Jul 1994 19:22:07 GMT
References: <1994Jul13.152207.5795@berkeley.edu>
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In article <1994Jul13.152207.5795@berkeley.edu>, jpark@berkeley.edu (Ji-woo Park) writes:
> Technical analysis of the sub-audible carrier: data and MATLAB code below.

Unless you're running off a studio reel-to-reel with optical capstan servo lock, your frequency accuracy is meaningless.

-- 
Tyler Eriksson -- University of Tokyo Department of Information Science
"Hardware is temporary. The signal survives."