From bduarte@pacbell.net Fri Aug 04 00:38:15 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!pacbell!bduarte From: bduarte@pacbell.net (Bill Duarte) Newsgroups: comp.dsp Subject: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Aug04.003815.2318@pacbell.net> Date: Fri, 04 Aug 1995 00:38:15 GMT Organization: Pacific Bell Internet Services NNTP-Posting-Host: pacbell.net X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. 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. -- Bill Duarte | bduarte@pacbell.net PGP Key fingerprint: 1BD1 D87D 1D60 84AA "Keep the channels open." From bsanchez@unam.mx Fri Aug 04 21:50:15 1995 Path: ashpoly!cascade!mxgate!coyoacan!unam!bsanchez From: bsanchez@unam.mx (Bruno Sánchez) Newsgroups: comp.dsp Subject: Re: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Aug04.215015.1578@unam.mx> Date: Fri, 04 Aug 1995 21:50:15 GMT References: <1995Aug04.003815.2318@pacbell.net> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Aug04.003815.2318@pacbell.net>, bduarte@pacbell.net (Bill Duarte) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. > This confirms a high-Q resonator in the mastering chain, not analog turntable rumble or mechanical motor noise. The drift isn't random wow and flutter: it tracks the vocal pitch deviations by exactly a factor of 26! -- Bruno Sánchez -- Universidad Nacional Autónoma de México (DGSCA) "In theory there is no difference between theory and practice." From dmuller@inria.fr Sat Aug 05 12:10:15 1995 Path: ashpoly!cascade!transat!ukc!fennimore!inria!dmuller From: dmuller@inria.fr (Diego Müller) Newsgroups: comp.dsp Subject: Re: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Aug05.121015.2600@inria.fr> Date: Sat, 05 Aug 1995 12:10:15 GMT References: <1995Aug04.003815.2318@pacbell.net> Organization: INRIA Rocquencourt NNTP-Posting-Host: inria.fr X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995Aug04.003815.2318@pacbell.net>, bduarte@pacbell.net (Bill Duarte) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. > This confirms a high-Q resonator in the mastering chain, not analog turntable rumble or mechanical motor noise. If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Diego Müller -- INRIA Rocquencourt "The carrier frequency does not drift by accident." From amacdonald@demon.co.uk Sun Aug 06 20:14:15 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!demon!amacdonald From: amacdonald@demon.co.uk (Anton MacDonald) Newsgroups: comp.dsp Subject: Re: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Aug06.201415.3269@demon.co.uk> Date: Sun, 06 Aug 1995 20:14:15 GMT References: <1995Aug04.003815.2318@pacbell.net> <1995Aug05.121015.2600@inria.fr> Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: TIN [version 1.2 PL2] Lines: 8 In article <1995Aug05.121015.2600@inria.fr>, dmuller@inria.fr (Diego Müller) writes: > If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. 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. -- Anton MacDonald Tape trading list upon request. SASE required for international mail. From hfischer@kiae.su Tue Aug 08 21:51:15 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!kiae!hfischer From: hfischer@kiae.su (Hana Fischer) Newsgroups: comp.dsp Subject: Re: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Aug08.215115.8881@kiae.su> Date: Tue, 08 Aug 1995 21:51:15 GMT References: <1995Aug04.003815.2318@pacbell.net> <1995Aug04.215015.1578@unam.mx> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Aug04.215015.1578@unam.mx>, bsanchez@unam.mx (Bruno Sánchez) writes: > The drift isn't random wow and flutter: it tracks the vocal pitch deviations by exactly a factor of 26! Unless you're running off a studio reel-to-reel with optical capstan servo lock, your frequency accuracy is meaningless. -- Hana Fischer "Hold for relay." Amiga 1200 (Blizzard 030/50) / NEXTSTEP 3.3