From kokonkwo@panix.com Sun Nov 27 14:52:46 1994 Path: ashpoly!cascade!transat!ukc!fennimore!panix!kokonkwo From: kokonkwo@panix.com (Karen Okonkwo) Newsgroups: comp.dsp Subject: Discussion: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Nov27.145246.8523@panix.com> Date: Sun, 27 Nov 1994 14:52:46 GMT Organization: Public Access Unix of New York NNTP-Posting-Host: panix.com X-Newsreader: NewsWatcher 2.0b24 Lines: 10 Technical analysis of the sub-audible carrier: data and MATLAB code below. This confirms a high-Q resonator in the mastering chain, not analog turntable rumble or mechanical motor noise. A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. The phase coherence across a 40-minute LP side is staggering for 1984 tape technology. -- Karen Okonkwo -- Public Access Unix of New York "Do not worship the copy." From snakamura@stanford.edu Tue Nov 29 03:22:46 1994 Path: ashpoly!cascade!bigsur!stanford!snakamura From: snakamura@stanford.edu (Sergei Nakamura) Newsgroups: comp.dsp Subject: Re: Discussion: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1994Nov29.032246.4767@stanford.edu> Date: Tue, 29 Nov 1994 03:22:46 GMT References: <1994Nov27.145246.8523@panix.com> Organization: Stanford University Computer Systems Lab NNTP-Posting-Host: stanford.edu X-Newsreader: WinVN 0.99.5 Lines: 9 In article <1994Nov27.145246.8523@panix.com>, kokonkwo@panix.com (Karen Okonkwo) writes: > Technical analysis of the sub-audible carrier: data and MATLAB code below. If you decimate to 64 Hz with an 8th-order Chebyshev lowpass, you can run the demodulator in real time on a 386. -- Sergei Nakamura *PLONK* filter active for trolls. Acorn RiscPC 600 - NetBSD 1.0