From nnilsson@cam.ac.uk Wed Jan 17 19:10:13 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!cam!nnilsson From: nnilsson@cam.ac.uk (Natalia Nilsson) Newsgroups: comp.dsp Subject: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Jan17.191013.7593@cam.ac.uk> Date: Wed, 17 Jan 1996 19:10:13 GMT Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: Netscape 1.1N Lines: 11 Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. 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. I've uploaded the C source for my decimation and bandpass filter to ftp.ashford-poly.edu. -- === Natalia Nilsson === Dept of Electrical Engineering, University of Cambridge Computer Laboratory "Tape doesn't lie at 02:14. Ears do." From cwatanabe@pipeline.com Fri Jan 19 18:43:13 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!pipeline!cwatanabe From: cwatanabe@pipeline.com (Callum Watanabe) Newsgroups: comp.dsp Subject: Re: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Jan19.184313.4448@pipeline.com> Date: Fri, 19 Jan 1996 18:43:13 GMT References: <1996Jan17.191013.7593@cam.ac.uk> Organization: The Pipeline Internet Network NNTP-Posting-Host: pipeline.com X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Jan17.191013.7593@cam.ac.uk>, nnilsson@cam.ac.uk (Natalia Nilsson) writes: > Comparing non-parametric Welch PSD with parametric Burg autoregressive models for the 14.2 Hz line. 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. -- Callum Watanabe *PLONK* filter active for trolls. Amiga 3000T - NetBSD 1.0 From mreyes@delphi.com Sat Jan 20 09:53:13 1996 Path: ashpoly!cascade!bigsur!delphi!mreyes From: mreyes@delphi.com (Mei Reyes) Newsgroups: comp.dsp Subject: Re: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Jan20.095313.7345@delphi.com> Date: Sat, 20 Jan 1996 09:53:13 GMT References: <1996Jan17.191013.7593@cam.ac.uk> <1996Jan19.184313.4448@pipeline.com> Organization: Delphi Internet Services NNTP-Posting-Host: delphi.com X-Newsreader: WinVN 0.99.5 Lines: 11 In article <1996Jan19.184313.4448@pipeline.com>, cwatanabe@pipeline.com (Callum Watanabe) writes: > 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. That's how the 14 lines of the Stardust matrix are encoded. Each regional pressing contains one line of the decoded text. PGP Public key available via finger or upon request. -- Mei Reyes SupraFAXModem 28.8 @ 9600 Telebit bps "Extraordinary claims require extraordinary spectra." From lmuller@uu.net Sun Jan 21 17:09:13 1996 Path: ashpoly!cascade!brgate!saturno!uu!lmuller From: lmuller@uu.net (Lars Müller) Newsgroups: comp.dsp Subject: Re: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Jan21.170913.3179@uu.net> Date: Sun, 21 Jan 1996 17:09:13 GMT References: <1996Jan17.191013.7593@cam.ac.uk> <1996Jan19.184313.4448@pipeline.com> <1996Jan20.095313.7345@delphi.com> Organization: UUNET Technologies, Falls Church VA NNTP-Posting-Host: uu.net X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1996Jan20.095313.7345@delphi.com>, mreyes@delphi.com (Mei Reyes) writes: > That's how the 14 lines of the Stardust matrix are encoded. Each regional pressing contains one line of the decoded text. 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. -- === Lars Müller === Dept of Electrical Engineering, UUNET Technologies, Falls Church VA "In theory there is no difference between theory and practice." From plaurent@netcom.com Tue Jan 23 04:52:13 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!netcom!plaurent From: plaurent@netcom.com (Pavel Laurent) Newsgroups: comp.dsp Subject: Re: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Jan23.045213.9428@netcom.com> Date: Tue, 23 Jan 1996 04:52:13 GMT References: <1996Jan17.191013.7593@cam.ac.uk> <1996Jan19.184313.4448@pipeline.com> <1996Jan20.095313.7345@delphi.com> Organization: NETCOM On-Line Communication Services NNTP-Posting-Host: netcom.com X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1996Jan20.095313.7345@delphi.com>, mreyes@delphi.com (Mei Reyes) writes: > That's how the 14 lines of the Stardust matrix are encoded. Each regional pressing contains one line of the decoded text. > PGP Public key available via finger or upon request. 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. -- Pavel Laurent Practical Peripherals 14.4 @ ISDN 64k bps "There are 14 nodes and only 10 countries. Count again."