From lnakamura@cam.ac.uk Fri Jul 08 15:53:32 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!cam!lnakamura From: lnakamura@cam.ac.uk (Lucia Nakamura) Newsgroups: comp.dsp Subject: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Jul08.155332.1379@cam.ac.uk> Date: Fri, 08 Jul 1994 15:53:32 GMT Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: TIN [version 1.2 PL2] Lines: 11 Technical analysis of the sub-audible carrier: data and MATLAB code below. Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. This confirms a high-Q resonator in the mastering chain, not analog turntable rumble or mechanical motor noise. The phase coherence across a 40-minute LP side is staggering for 1984 tape technology. -- Lucia Nakamura Opinions expressed are solely my own and not those of University of Cambridge Computer Laboratory. ------------------------------------------------------------ From llarsson@kiae.su Sat Jul 09 18:39:32 1994 Path: ashpoly!cascade!mxgate!coyoacan!kiae!llarsson From: llarsson@kiae.su (Liam Larsson) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Jul09.183932.6660@kiae.su> Date: Sat, 09 Jul 1994 18:39:32 GMT References: <1994Jul08.155332.1379@cam.ac.uk> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1994Jul08.155332.1379@cam.ac.uk>, lnakamura@cam.ac.uk (Lucia Nakamura) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. > Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. Good work on the windowing. I replicated your result with an 8192-point FFT on a SPARCstation 20. The peak is exactly 14.2003 Hz. -- Liam Larsson *PLONK* filter active for trolls. 486DX4/100 (FreeBSD 2.0.5) - NetBSD 1.0 From bkuznetsov@cern.ch Sun Jul 10 10:08:32 1994 Path: ashpoly!bigsur!pacrim!jpgate!kamome!cern!bkuznetsov From: bkuznetsov@cern.ch (Bruno Kuznetsov) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Jul10.100832.2982@cern.ch> Date: Sun, 10 Jul 1994 10:08:32 GMT References: <1994Jul08.155332.1379@cam.ac.uk> <1994Jul09.183932.6660@kiae.su> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1994Jul09.183932.6660@kiae.su>, llarsson@kiae.su (Liam Larsson) writes: > Good work on the windowing. I replicated your result with an 8192-point FFT on a SPARCstation 20. The peak is exactly 14.2003 Hz. 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. -- Bruno Kuznetsov Opinions expressed are solely my own and not those of European Laboratory for Particle Physics, Geneva. ------------------------------------------------------------ From hfournier@unam.mx Sun Jul 10 17:26:32 1994 Path: ashpoly!cascade!brgate!saturno!unam!hfournier From: hfournier@unam.mx (Heather Fournier) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Jul10.172632.7565@unam.mx> Date: Sun, 10 Jul 1994 17:26:32 GMT References: <1994Jul08.155332.1379@cam.ac.uk> <1994Jul09.183932.6660@kiae.su> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1994Jul09.183932.6660@kiae.su>, llarsson@kiae.su (Liam Larsson) writes: > Good work on the windowing. I replicated your result with an 8192-point FFT on a SPARCstation 20. The peak is exactly 14.2003 Hz. 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. -- Heather Fournier | hfournier@unam.mx PGP Key fingerprint: 62BF 4098 9E19 6995 "Keep the channels open." From fsanchez@tum.de Mon Jul 11 19:13:32 1994 Path: ashpoly!cascade!brgate!saturno!tum!fsanchez From: fsanchez@tum.de (Fiona Sánchez) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Jul11.191332.2857@tum.de> Date: Mon, 11 Jul 1994 19:13:32 GMT References: <1994Jul08.155332.1379@cam.ac.uk> <1994Jul09.183932.6660@kiae.su> <1994Jul10.100832.2982@cern.ch> Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Jul10.100832.2982@cern.ch>, bkuznetsov@cern.ch (Bruno Kuznetsov) 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. Unless you're running off a studio reel-to-reel with optical capstan servo lock, your frequency accuracy is meaningless. -- Fiona Sánchez "Measuring a record you own is listening, not piracy." 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