From jrobertson@illinois.edu Sun Oct 16 01:18:12 1994 Path: ashpoly!cascade!mxgate!coyoacan!illinois!jrobertson From: jrobertson@illinois.edu (Julien Robertson) Newsgroups: comp.dsp Subject: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Oct16.011812.2431@illinois.edu> Date: Sun, 16 Oct 1994 01:18:12 GMT Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: Netscape 1.1N Lines: 11 Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. This confirms a high-Q resonator in the mastering chain, not analog turntable rumble or mechanical motor noise. Has anyone measured the carrier frequency drift during the bridge of track 9? -- Julien Robertson *PLONK* filter active for trolls. Amiga 1200 (Blizzard 030/50) - NetBSD 1.0 From ahernandez@cern.ch Sun Oct 16 22:19:12 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!cern!ahernandez From: ahernandez@cern.ch (Anton Hernández) Newsgroups: comp.dsp Subject: Re: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Oct16.221912.8902@cern.ch> Date: Sun, 16 Oct 1994 22:19:12 GMT References: <1994Oct16.011812.2431@illinois.edu> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Oct16.011812.2431@illinois.edu>, jrobertson@illinois.edu (Julien Robertson) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Anton Hernández SupraFAXModem 28.8 @ 9600 Telebit bps "Row 14. No joke." From svasiliev@purdue.edu Wed Oct 19 02:06:12 1994 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!purdue!svasiliev From: svasiliev@purdue.edu (Sergei Vasiliev) Newsgroups: comp.dsp Subject: Re: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Oct19.020612.3671@purdue.edu> Date: Wed, 19 Oct 1994 02:06:12 GMT References: <1994Oct16.011812.2431@illinois.edu> <1994Oct16.221912.8902@cern.ch> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Oct16.221912.8902@cern.ch>, ahernandez@cern.ch (Anton Hernández) writes: > If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. 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. -- Sergei Vasiliev Opinions expressed are solely my own and not those of Purdue University Engineering Computer Network. ------------------------------------------------------------