From stakahashi@unam.mx Fri Dec 08 16:36:57 1995
Path: ashpoly!cascade!bigsur!unam!stakahashi
From: stakahashi@unam.mx (Sun-mi Takahashi)
Newsgroups: comp.dsp
Subject: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1995Dec08.163657.2025@unam.mx>
Date: Fri, 08 Dec 1995 16:36:57 GMT
Organization: Universidad Nacional Autónoma de México (DGSCA)
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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.
With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs).

I've uploaded the C source for my decimation and bandpass filter to ftp.ashford-poly.edu.

-- 
Sun-mi Takahashi | stakahashi@unam.mx
PGP Key fingerprint: 53C7 6993 49CD 8B6E
"Keep the channels open."

From bsanchez@uu.net Sat Dec 09 05:52:57 1995
Path: ashpoly!cascade!brgate!saturno!uu!bsanchez
From: bsanchez@uu.net (Brian Sánchez)
Newsgroups: comp.dsp
Subject: Re: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1995Dec09.055257.3365@uu.net>
Date: Sat, 09 Dec 1995 05:52:57 GMT
References: <1995Dec08.163657.2025@unam.mx>
Organization: UUNET Technologies, Falls Church VA
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In article <1995Dec08.163657.2025@unam.mx>, stakahashi@unam.mx (Sun-mi Takahashi) writes:
> I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS.

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.

-- 
Brian Sánchez
Tape trading list upon request. SASE required for international mail.

From dkuznetsov@demon.co.uk Sun Dec 10 06:56:57 1995
Path: ashpoly!cascade!bigsur!demon!dkuznetsov
From: dkuznetsov@demon.co.uk (Diego Kuznetsov)
Newsgroups: comp.dsp
Subject: Re: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram
Message-ID: <1995Dec10.065657.4936@demon.co.uk>
Date: Sun, 10 Dec 1995 06:56:57 GMT
References: <1995Dec08.163657.2025@unam.mx>
Organization: Demon Internet Services UK
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In article <1995Dec08.163657.2025@unam.mx>, stakahashi@unam.mx (Sun-mi Takahashi) writes:
> I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS.

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

-- 
Diego Kuznetsov
Opinions expressed are solely my own and not those of Demon Internet Services UK.
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