From mhughes@illinois.edu Sat Jun 04 12:47:54 1994 Path: ashpoly!cascade!transat!eunet-fr!teletel!illinois!mhughes From: mhughes@illinois.edu (Morag Hughes) Newsgroups: comp.dsp Subject: Discussion: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Jun04.124754.1600@illinois.edu> Date: Sat, 04 Jun 1994 12:47:54 GMT Organization: University of Illinois Urbana-Champaign NNTP-Posting-Host: illinois.edu X-Newsreader: WinVN 0.99.5 Lines: 10 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. 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. -- Morag Hughes -- University of Illinois Urbana-Champaign "Hardware is temporary. The signal survives." From dvasiliev@unam.mx Sat Jun 04 20:31:54 1994 Path: ashpoly!cascade!transat!sunet!nordrelay!unam!dvasiliev From: dvasiliev@unam.mx (Dmitri Vasiliev) Newsgroups: comp.dsp Subject: Re: Discussion: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Jun04.203154.1951@unam.mx> Date: Sat, 04 Jun 1994 20:31:54 GMT References: <1994Jun04.124754.1600@illinois.edu> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: Netscape 1.1N Lines: 12 In article <1994Jun04.124754.1600@illinois.edu>, mhughes@illinois.edu (Morag Hughes) 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. If you are posting from AOL, please read RFC 1036 before posting again. -- Dmitri Vasiliev "The carrier frequency does not drift by accident." Atari TT030 / SunOS 4.1.4 From mreyes@mindspring.com Sat Jun 04 22:49:54 1994 Path: ashpoly!bigsur!pacrim!krgate!eunha!mindspring!mreyes From: mreyes@mindspring.com (Mathieu Reyes) Newsgroups: comp.dsp Subject: Re: Discussion: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Jun04.224954.6070@mindspring.com> Date: Sat, 04 Jun 1994 22:49:54 GMT References: <1994Jun04.124754.1600@illinois.edu> <1994Jun04.203154.1951@unam.mx> Organization: MindSpring Enterprises NNTP-Posting-Host: mindspring.com X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1994Jun04.203154.1951@unam.mx>, dvasiliev@unam.mx (Dmitri Vasiliev) writes: > Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature. > If you are posting from AOL, please read RFC 1036 before posting again. Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature. -- Mathieu Reyes "Measuring a record you own is listening, not piracy." Macintosh IIfx / NEXTSTEP 3.3 From awatanabe@cam.ac.uk Sun Jun 05 03:03:54 1994 Path: ashpoly!bigsur!pacrim!jpgate!kamome!cam!awatanabe From: awatanabe@cam.ac.uk (Andrei Watanabe) Newsgroups: comp.dsp Subject: Re: Discussion: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Jun05.030354.5656@cam.ac.uk> Date: Sun, 05 Jun 1994 03:03:54 GMT References: <1994Jun04.124754.1600@illinois.edu> <1994Jun04.203154.1951@unam.mx> <1994Jun04.224954.6070@mindspring.com> Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: NewsWatcher 2.0b24 Lines: 11 In article <1994Jun04.224954.6070@mindspring.com>, mreyes@mindspring.com (Mathieu Reyes) writes: > Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature. If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! -- Andrei Watanabe "They will send a copy in my place." Pentium 90 (OS/2 Warp) / AmigaOS 3.1 From jlarsson@unam.mx Tue Jun 07 02:41:54 1994 Path: ashpoly!cascade!bigsur!unam!jlarsson From: jlarsson@unam.mx (Ji-woo Larsson) Newsgroups: comp.dsp Subject: Re: Discussion: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Jun07.024154.2278@unam.mx> Date: Tue, 07 Jun 1994 02:41:54 GMT References: <1994Jun04.124754.1600@illinois.edu> <1994Jun04.203154.1951@unam.mx> Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1994Jun04.203154.1951@unam.mx>, dvasiliev@unam.mx (Dmitri Vasiliev) writes: > Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature. 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. -- Ji-woo Larsson Opinions expressed are solely my own and not those of Universidad Nacional Autónoma de México (DGSCA). ------------------------------------------------------------