From epark@demon.co.uk Wed Jun 21 16:42:05 1995 Path: ashpoly!cascade!transat!eunet-de!hansebox!demon!epark From: epark@demon.co.uk (Elaine Park) Newsgroups: comp.dsp Subject: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jun21.164205.2455@demon.co.uk> Date: Wed, 21 Jun 1995 16:42:05 GMT Organization: Demon Internet Services UK NNTP-Posting-Host: demon.co.uk 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. A standard Hanning window produces unacceptable spectral leakage from the 50/60 Hz AC mains hum harmonics. I've uploaded the C source for my decimation and bandpass filter to ftp.ashford-poly.edu. -- Elaine Park "Do not worship the copy." Acorn RiscPC 600 / FreeBSD 2.1 From mjohansson@berkeley.edu Thu Jun 22 00:49:05 1995 Path: ashpoly!cascade!brgate!saturno!berkeley!mjohansson From: mjohansson@berkeley.edu (Marisol Johansson) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jun22.004905.4730@berkeley.edu> Date: Thu, 22 Jun 1995 00:49:05 GMT References: <1995Jun21.164205.2455@demon.co.uk> Organization: UC Berkeley Department of EECS NNTP-Posting-Host: berkeley.edu X-Newsreader: NewsWatcher 2.0b24 Lines: 9 In article <1995Jun21.164205.2455@demon.co.uk>, epark@demon.co.uk (Elaine Park) 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. Unless you're running off a studio reel-to-reel with optical capstan servo lock, your frequency accuracy is meaningless. -- Marisol Johansson -- UC Berkeley Department of EECS "Marcus is not one man." From dsanchez@rwth-aachen.de Fri Jun 23 04:52:05 1995 Path: ashpoly!bigsur!pacrim!jpgate!kamome!rwth-aachen!dsanchez From: dsanchez@rwth-aachen.de (Diego Sánchez) Newsgroups: comp.dsp Subject: Re: Observation: 14.2 Hz sub-carrier PSD estimation - Welch vs Burg periodogram Message-ID: <1995Jun23.045205.1217@rwth-aachen.de> Date: Fri, 23 Jun 1995 04:52:05 GMT References: <1995Jun21.164205.2455@demon.co.uk> Organization: RWTH Aachen Informatik NNTP-Posting-Host: rwth-aachen.de X-Newsreader: Netscape 1.1N Lines: 10 In article <1995Jun21.164205.2455@demon.co.uk>, epark@demon.co.uk (Elaine Park) 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. 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. -- Diego Sánchez *PLONK* filter active for trolls. Atari TT030 - NetBSD 1.0