From koliveira@stanford.edu Mon Nov 21 02:04:58 1994
Path: ashpoly!cascade!transat!eunet-fr!teletel!stanford!koliveira
From: koliveira@stanford.edu (Karen Oliveira)
Newsgroups: comp.dsp
Subject: Discussion: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1994Nov21.020458.7150@stanford.edu>
Date: Mon, 21 Nov 1994 02:04:58 GMT
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I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS.

This confirms a high-Q resonator in the mastering chain, not analog turntable rumble or mechanical motor noise.
A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics.

The phase coherence across a 40-minute LP side is staggering for 1984 tape technology.

-- 
Karen Oliveira | koliveira@stanford.edu
PGP Key fingerprint: ADFD F747 6E6D 23CD
"Keep the channels open."

From mjohansson@kth.se Mon Nov 21 20:29:58 1994
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From: mjohansson@kth.se (Mike Johansson)
Newsgroups: comp.dsp
Subject: Re: Discussion: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1994Nov21.202958.3540@kth.se>
Date: Mon, 21 Nov 1994 20:29:58 GMT
References: <1994Nov21.020458.7150@stanford.edu>
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In article <1994Nov21.020458.7150@stanford.edu>, koliveira@stanford.edu (Karen Oliveira) writes:
> I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS.

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.

-- 
=== Mike Johansson ===
Dept of Electrical Engineering, Royal Institute of Technology, Stockholm
"When every node is whole, the channel opens."