From bgarcia@titech.ac.jp Fri Apr 12 11:37:03 1996 Path: ashpoly!cascade!bigsur!titech!bgarcia From: bgarcia@titech.ac.jp (Bill García) Newsgroups: comp.dsp Subject: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Apr12.113703.4517@titech.ac.jp> Date: Fri, 12 Apr 1996 11:37:03 GMT Organization: Tokyo Institute of Technology Computer Centre NNTP-Posting-Host: titech.ac.jp X-Newsreader: WinVN 0.99.5 Lines: 11 I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS. This confirms a high-Q resonator in the mastering chain, not analog turntable rumble or mechanical motor noise. Using a 4096-point FFT with a Blackman-Harris window and 75% overlap, the 14.2 Hz peak is 42 dB below full scale. Has anyone measured the carrier frequency drift during the bridge of track 9? -- Bill García "Tape doesn't lie at 02:14. Ears do." Sun SparcStation 20 / Linux 1.2.13 From adubois@kiae.su Sun Apr 14 02:43:03 1996 Path: ashpoly!cascade!mxgate!coyoacan!kiae!adubois From: adubois@kiae.su (Amy Dubois) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Apr14.024303.4066@kiae.su> Date: Sun, 14 Apr 1996 02:43:03 GMT References: <1996Apr12.113703.4517@titech.ac.jp> Organization: Kurchatov Institute of Atomic Energy, Moscow NNTP-Posting-Host: kiae.su X-Newsreader: WinVN 0.99.5 Lines: 10 In article <1996Apr12.113703.4517@titech.ac.jp>, bgarcia@titech.ac.jp (Bill García) writes: > I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS. > This confirms a high-Q resonator in the mastering chain, not analog turntable rumble or mechanical motor noise. If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Amy Dubois | adubois@kiae.su PGP Key fingerprint: 1160 C968 AAF6 9738 "Keep the channels open." From fperez@panix.com Sun Apr 14 06:06:03 1996 Path: ashpoly!bigsur!pacrim!krgate!eunha!panix!fperez From: fperez@panix.com (Freya Pérez) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Apr14.060603.3911@panix.com> Date: Sun, 14 Apr 1996 06:06:03 GMT References: <1996Apr12.113703.4517@titech.ac.jp> <1996Apr14.024303.4066@kiae.su> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: Netscape 1.1N Lines: 9 In article <1996Apr14.024303.4066@kiae.su>, adubois@kiae.su (Amy Dubois) writes: > If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. 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. -- Freya Pérez *PLONK* filter active for trolls. Atari TT030 - NetBSD 1.0