From lokonkwo@rwth-aachen.de Mon Aug 12 12:28:32 1996 Path: ashpoly!cascade!bigsur!rwth-aachen!lokonkwo From: lokonkwo@rwth-aachen.de (Lars Okonkwo) Newsgroups: comp.dsp Subject: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Aug12.122832.7740@rwth-aachen.de> Date: Mon, 12 Aug 1996 12:28:32 GMT Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: TIN [version 1.2 PL2] 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. 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. -- Lars Okonkwo | lokonkwo@rwth-aachen.de PGP Key fingerprint: 478F 87A1 FA27 BA6C "Keep the channels open." From esuzuki@clari.net Tue Aug 13 04:45:32 1996 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!clari!esuzuki From: esuzuki@clari.net (Élodie Suzuki) Newsgroups: comp.dsp Subject: Re: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Aug13.044532.9368@clari.net> Date: Tue, 13 Aug 1996 04:45:32 GMT References: <1996Aug12.122832.7740@rwth-aachen.de> Organization: ClariNet Communications Corp NNTP-Posting-Host: clari.net X-Newsreader: Netscape 1.1N Lines: 10 In article <1996Aug12.122832.7740@rwth-aachen.de>, lokonkwo@rwth-aachen.de (Lars Okonkwo) 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. If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Élodie Suzuki *PLONK* filter active for trolls. 486DX4/100 (FreeBSD 2.0.5) - NetBSD 1.0 From ktanaka@panix.com Tue Aug 13 19:38:32 1996 Path: ashpoly!cascade!mxgate!coyoacan!panix!ktanaka From: ktanaka@panix.com (Kenji Tanaka) Newsgroups: comp.dsp Subject: Re: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Aug13.193832.2919@panix.com> Date: Tue, 13 Aug 1996 19:38:32 GMT References: <1996Aug12.122832.7740@rwth-aachen.de> <1996Aug13.044532.9368@clari.net> Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: Netscape 1.1N Lines: 11 In article <1996Aug13.044532.9368@clari.net>, esuzuki@clari.net (Élodie Suzuki) 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. Unsubscribe me from this list! (Wait, this is Usenet, never mind). -- === Kenji Tanaka === Dept of Electrical Engineering, Public Access Unix of New York "They will send a copy in my place." From ssmirnov@demon.co.uk Wed Aug 14 03:20:32 1996 Path: ashpoly!cascade!transat!eunet-fr!teletel!demon!ssmirnov From: ssmirnov@demon.co.uk (Sergei Smirnov) Newsgroups: comp.dsp Subject: Re: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Aug14.032032.9777@demon.co.uk> Date: Wed, 14 Aug 1996 03:20:32 GMT References: <1996Aug12.122832.7740@rwth-aachen.de> <1996Aug13.044532.9368@clari.net> Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk X-Newsreader: Netscape 1.1N Lines: 11 In article <1996Aug13.044532.9368@clari.net>, esuzuki@clari.net (Élodie Suzuki) 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. My 14.4k connection dropped twice trying to fetch this thread. Keep articles concise! -- Sergei Smirnov "They will send a copy in my place." NeXTstation Turbo Color / NEXTSTEP 3.3 From gkim@uni-hamburg.de Thu Aug 15 21:52:32 1996 Path: ashpoly!cascade!transat!eunet-de!hansebox!uni-hamburg!gkim From: gkim@uni-hamburg.de (Göran Kim) Newsgroups: comp.dsp Subject: Re: [SPECULATION] 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1996Aug15.215232.7587@uni-hamburg.de> Date: Thu, 15 Aug 1996 21:52:32 GMT References: <1996Aug12.122832.7740@rwth-aachen.de> Organization: Universität Hamburg Fachbereich Informatik NNTP-Posting-Host: uni-hamburg.de X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1996Aug12.122832.7740@rwth-aachen.de>, lokonkwo@rwth-aachen.de (Lars Okonkwo) writes: > I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS. 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. Netscape 1.1 crashes when loading large preformatted text. Stick to rn or tin! -- Göran Kim -- Universität Hamburg Fachbereich Informatik "Do not worship the copy."