From vandersson@unam.mx Sun Jun 25 18:01:17 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!unam!vandersson From: vandersson@unam.mx (Valeria Andersson) Newsgroups: comp.dsp Subject: [INFO] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jun25.180117.5607@unam.mx> Date: Sun, 25 Jun 1995 18:01:17 GMT Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: WinVN 0.99.5 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. Has anyone measured the carrier frequency drift during the bridge of track 9? -- Valeria Andersson Practical Peripherals 14.4 @ 9600 Telebit bps "Hardware is temporary. The signal survives." From klee@uni-hamburg.de Mon Jun 26 04:27:17 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!uni-hamburg!klee From: klee@uni-hamburg.de (Kirsty Lee) Newsgroups: comp.dsp Subject: Re: [INFO] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jun26.042717.3868@uni-hamburg.de> Date: Mon, 26 Jun 1995 04:27:17 GMT References: <1995Jun25.180117.5607@unam.mx> Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: WinVN 0.99.5 Lines: 12 In article <1995Jun25.180117.5607@unam.mx>, vandersson@unam.mx (Valeria Andersson) 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. If you are posting from AOL, please read RFC 1036 before posting again. -- Kirsty Lee "Measuring a record you own is listening, not piracy." 486DX2/66 (Linux 1.2.13) / AmigaOS 3.1 From fduarte@ox.ac.uk Tue Jun 27 13:58:17 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!ox!fduarte From: fduarte@ox.ac.uk (Freya Duarte) Newsgroups: comp.dsp Subject: Re: [INFO] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jun27.135817.5569@ox.ac.uk> Date: Tue, 27 Jun 1995 13:58:17 GMT References: <1995Jun25.180117.5607@unam.mx> <1995Jun26.042717.3868@uni-hamburg.de> Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Jun26.042717.3868@uni-hamburg.de>, klee@uni-hamburg.de (Kirsty Lee) 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. -- Freya Duarte "They will send a copy in my place." Acorn RiscPC 600 / NEXTSTEP 3.3