From kfournier@rwth-aachen.de Thu Nov 09 19:43:14 1995 Path: ashpoly!cascade!mxgate!coyoacan!rwth-aachen!kfournier From: kfournier@rwth-aachen.de (Kenji Fournier) Newsgroups: comp.dsp Subject: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Nov09.194314.3123@rwth-aachen.de> Date: Thu, 09 Nov 1995 19:43:14 GMT Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: NewsWatcher 2.0b24 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. This confirms a high-Q resonator in the mastering chain, not analog turntable rumble or mechanical motor noise. Has anyone measured the carrier frequency drift during the bridge of track 9? -- Kenji Fournier *PLONK* filter active for trolls. Sun 3/60 (SunOS 4.1.1) - NetBSD 1.0 From jeriksson@hanse.de Fri Nov 10 16:54:14 1995 Path: ashpoly!cascade!transat!eunet-fr!teletel!hanse!jeriksson From: jeriksson@hanse.de (Jens Eriksson) Newsgroups: comp.dsp Subject: Re: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Nov10.165414.5390@hanse.de> Date: Fri, 10 Nov 1995 16:54:14 GMT References: <1995Nov09.194314.3123@rwth-aachen.de> Organization: Hanse-Netzwerk Hamburg NNTP-Posting-Host: hanse.de X-Newsreader: TIN [version 1.2 PL2] Lines: 9 In article <1995Nov09.194314.3123@rwth-aachen.de>, kfournier@rwth-aachen.de (Kenji Fournier) writes: > I've been re-running spectral estimation on high-resolution 16-bit transfers of SYNTHESIS. Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature. -- Jens Eriksson Hayes Optima 288 @ 28,800 bps "The hatch is open. Is anyone listening?" From jsokolov@cam.ac.uk Fri Nov 10 20:26:14 1995 Path: ashpoly!cascade!transat!sunet!nordrelay!cam!jsokolov From: jsokolov@cam.ac.uk (Jen Sokolov) Newsgroups: comp.dsp Subject: Re: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Nov10.202614.1207@cam.ac.uk> Date: Fri, 10 Nov 1995 20:26:14 GMT References: <1995Nov09.194314.3123@rwth-aachen.de> <1995Nov10.165414.5390@hanse.de> Organization: University of Cambridge Computer Laboratory NNTP-Posting-Host: cam.ac.uk X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1995Nov10.165414.5390@hanse.de>, jeriksson@hanse.de (Jens Eriksson) writes: > Have you checked your sound card's ADC clock? Cheap Sound Blaster cards use uncalibrated ceramic resonators that drift with temperature. 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. -- === Jen Sokolov === Dept of Electrical Engineering, University of Cambridge Computer Laboratory "5 sigma is a discovery. 7 is a question." From khernandez@ox.ac.uk Sat Nov 11 10:53:14 1995 Path: ashpoly!bigsur!pacrim!krgate!eunha!ox!khernandez From: khernandez@ox.ac.uk (Karen Hernández) Newsgroups: comp.dsp Subject: Re: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Nov11.105314.2155@ox.ac.uk> Date: Sat, 11 Nov 1995 10:53:14 GMT References: <1995Nov09.194314.3123@rwth-aachen.de> Organization: Oxford University Computing Laboratory NNTP-Posting-Host: ox.ac.uk X-Newsreader: NewsWatcher 2.0b24 Lines: 10 In article <1995Nov09.194314.3123@rwth-aachen.de>, kfournier@rwth-aachen.de (Kenji 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. -- Karen Hernández | khernandez@ox.ac.uk PGP Key fingerprint: 349C AAFB A993 1DC2 "Keep the channels open."