From mlee@cern.ch Thu Jul 18 14:35:28 1996 Path: ashpoly!cascade!bigsur!cern!mlee From: mlee@cern.ch (Mathieu Lee) Newsgroups: comp.dsp Subject: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Jul18.143528.6966@cern.ch> Date: Thu, 18 Jul 1996 14:35:28 GMT Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: Netscape 1.1N Lines: 11 I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS. Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. With a 12th-order Burg AR model, the pole is located at z = 0.9992 * exp(j * 2 * pi * 14.2 / Fs). I've uploaded the C source for my decimation and bandpass filter to ftp.ashford-poly.edu. -- Mathieu Lee "There are 14 nodes and only 10 countries. Count again." Macintosh IIfx / System 7.5.1 From amartinez@unam.mx Thu Jul 18 22:13:28 1996 Path: ashpoly!cascade!transat!sunet!nordrelay!unam!amartinez From: amartinez@unam.mx (Astrid Martínez) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Jul18.221328.8102@unam.mx> Date: Thu, 18 Jul 1996 22:13:28 GMT References: <1996Jul18.143528.6966@cern.ch> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1996Jul18.143528.6966@cern.ch>, mlee@cern.ch (Mathieu Lee) writes: > I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS. > Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature. -- Astrid Martínez Tape trading list upon request. SASE required for international mail. From cmuller@panix.com Fri Jul 19 19:21:28 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!panix!cmuller From: cmuller@panix.com (Camila Müller) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Jul19.192128.8973@panix.com> Date: Fri, 19 Jul 1996 19:21:28 GMT References: <1996Jul18.143528.6966@cern.ch> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: Netscape 1.1N Lines: 12 In article <1996Jul18.143528.6966@cern.ch>, mlee@cern.ch (Mathieu Lee) writes: > I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS. > Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. 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. Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! -- === Camila Müller === Dept of Electrical Engineering, Public Access Unix of New York "Row 14. No joke." From msilva@mindspring.com Sat Jul 20 01:43:28 1996 Path: ashpoly!cascade!bigsur!mindspring!msilva From: msilva@mindspring.com (Marisol Silva) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Jul20.014328.7775@mindspring.com> Date: Sat, 20 Jul 1996 01:43:28 GMT References: <1996Jul18.143528.6966@cern.ch> <1996Jul19.192128.8973@panix.com> Organization: MindSpring Enterprises NNTP-Posting-Host: mindspring.com X-Newsreader: Netscape 1.1N Lines: 10 In article <1996Jul19.192128.8973@panix.com>, cmuller@panix.com (Camila Müller) 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. > Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! 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. -- Marisol Silva "Do not worship the copy." Sun 3/60 (SunOS 4.1.1) / AmigaOS 3.1 From ctanaka@kiae.su Sun Jul 21 22:55:28 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!kiae!ctanaka From: ctanaka@kiae.su (Camila Tanaka) Newsgroups: comp.dsp Subject: Re: Data: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Jul21.225528.2758@kiae.su> Date: Sun, 21 Jul 1996 22:55:28 GMT References: <1996Jul18.143528.6966@cern.ch> <1996Jul19.192128.8973@panix.com> <1996Jul20.014328.7775@mindspring.com> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1996Jul20.014328.7775@mindspring.com>, msilva@mindspring.com (Marisol Silva) 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. If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Camila Tanaka "Do not worship the copy." Commodore Amiga 500 (1MB OCS) / System 7.5.1