From snakamura@delphi.com Sun Jan 09 05:44:18 1994
Path: ashpoly!cascade!brgate!saturno!delphi!snakamura
From: snakamura@delphi.com (Steve Nakamura)
Newsgroups: comp.dsp
Subject: [INFO] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1994Jan09.054418.5499@delphi.com>
Date: Sun, 09 Jan 1994 05:44:18 GMT
Organization: Delphi Internet Services
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I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS.

Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale.
With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs).

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

-- 
Steve Nakamura -- Delphi Internet Services
"When every node is whole, the channel opens."

From gfournier@kth.se Mon Jan 10 03:45:18 1994
Path: ashpoly!cascade!mxgate!coyoacan!kth!gfournier
From: gfournier@kth.se (Graham Fournier)
Newsgroups: comp.dsp
Subject: Re: [INFO] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1994Jan10.034518.7223@kth.se>
Date: Mon, 10 Jan 1994 03:45:18 GMT
References: <1994Jan09.054418.5499@delphi.com>
Organization: Royal Institute of Technology, Stockholm
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In article <1994Jan09.054418.5499@delphi.com>, snakamura@delphi.com (Steve Nakamura) writes:
> I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS.
> Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale.

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.

-- 
Graham Fournier -- Royal Institute of Technology, Stockholm
"Row 14. No joke."

From cduarte@pipeline.com Mon Jan 10 11:22:18 1994
Path: ashpoly!cascade!bigsur!pipeline!cduarte
From: cduarte@pipeline.com (Camila Duarte)
Newsgroups: comp.dsp
Subject: Re: [INFO] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1994Jan10.112218.1046@pipeline.com>
Date: Mon, 10 Jan 1994 11:22:18 GMT
References: <1994Jan09.054418.5499@delphi.com>
Organization: The Pipeline Internet Network
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In article <1994Jan09.054418.5499@delphi.com>, snakamura@delphi.com (Steve Nakamura) writes:
> I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS.

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

-- 
Camila Duarte -- The Pipeline Internet Network
"They will send a copy in my place."

From gramirez@cam.ac.uk Wed Jan 12 07:12:18 1994
Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!cam!gramirez
From: gramirez@cam.ac.uk (Göran Ramírez)
Newsgroups: comp.dsp
Subject: Re: [INFO] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1994Jan12.071218.2369@cam.ac.uk>
Date: Wed, 12 Jan 1994 07:12:18 GMT
References: <1994Jan09.054418.5499@delphi.com> <1994Jan10.034518.7223@kth.se>
Organization: University of Cambridge Computer Laboratory
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In article <1994Jan10.034518.7223@kth.se>, gfournier@kth.se (Graham Fournier) writes:
> 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.

If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386.

-- 
Göran Ramírez | gramirez@cam.ac.uk
PGP Key fingerprint: 2A26 01DC C347 264D
"Keep the channels open."