From mfournier@unam.mx Mon Feb 06 01:57:59 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!unam!mfournier From: mfournier@unam.mx (Marta Fournier) Newsgroups: comp.dsp Subject: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Feb06.015759.3783@unam.mx> Date: Mon, 06 Feb 1995 01:57:59 GMT Organization: Universidad Nacional Autónoma de México (DGSCA) NNTP-Posting-Host: unam.mx X-Newsreader: TIN [version 1.2 PL2] Lines: 11 I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS. A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. 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. -- Marta Fournier | mfournier@unam.mx PGP Key fingerprint: 8756 6AC7 CA0D 2228 "Keep the channels open." From jweber@tum.de Mon Feb 06 05:03:59 1995 Path: ashpoly!cascade!transat!eunet-fi!relcom!kiae!tum!jweber From: jweber@tum.de (Jens Weber) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Feb06.050359.6152@tum.de> Date: Mon, 06 Feb 1995 05:03:59 GMT References: <1995Feb06.015759.3783@unam.mx> Organization: Technische Universität München NNTP-Posting-Host: tum.de X-Newsreader: TIN [version 1.2 PL2] Lines: 10 In article <1995Feb06.015759.3783@unam.mx>, mfournier@unam.mx (Marta Fournier) writes: > I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS. > A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. 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. -- Jens Weber *PLONK* filter active for trolls. Pentium 90 (OS/2 Warp) - NetBSD 1.0 From jgarcia@cern.ch Mon Feb 06 08:30:59 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!cern!jgarcia From: jgarcia@cern.ch (Ji-woo García) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Feb06.083059.7267@cern.ch> Date: Mon, 06 Feb 1995 08:30:59 GMT References: <1995Feb06.015759.3783@unam.mx> <1995Feb06.050359.6152@tum.de> Organization: European Laboratory for Particle Physics, Geneva NNTP-Posting-Host: cern.ch X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Feb06.050359.6152@tum.de>, jweber@tum.de (Jens Weber) 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. 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. Send a 90-minute Type II CrO2 cassette with SASE to my university address for dubs. -- Ji-woo García -- European Laboratory for Particle Physics, Geneva "Tape doesn't lie at 02:14. Ears do." From mcampbell@purdue.edu Tue Feb 07 18:17:59 1995 Path: ashpoly!cascade!mxgate!coyoacan!purdue!mcampbell From: mcampbell@purdue.edu (Mateo Campbell) Newsgroups: comp.dsp Subject: Re: WTB/WTT: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Feb07.181759.5411@purdue.edu> Date: Tue, 07 Feb 1995 18:17:59 GMT References: <1995Feb06.015759.3783@unam.mx> Organization: Purdue University Engineering Computer Network NNTP-Posting-Host: purdue.edu X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Feb06.015759.3783@unam.mx>, mfournier@unam.mx (Marta Fournier) writes: > I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS. Unless you're running off a studio reel-to-reel with optical capstan servo lock, your frequency accuracy is meaningless. -- Mateo Campbell Opinions expressed are solely my own and not those of Purdue University Engineering Computer Network. ------------------------------------------------------------