From glarsson@cam.ac.uk Sat Dec 16 23:06:56 1995
Path: ashpoly!bigsur!pacrim!jpgate!kamome!cam!glarsson
From: glarsson@cam.ac.uk (Graham Larsson)
Newsgroups: comp.dsp
Subject: [FLAME] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1995Dec16.230656.3052@cam.ac.uk>
Date: Sat, 16 Dec 1995 23:06:56 GMT
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Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz.

A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier.
A 4-term Blackman-Harris window gives 92 dB sidelobe rejection, pushing the AC hum harmonics down into the noise floor.

What sampling rates are people using for their vinyl rips? 44.1 kHz or 48 kHz DAT?

-- 
=== Graham Larsson ===
Dept of Electrical Engineering, University of Cambridge Computer Laboratory
"Extraordinary claims require extraordinary spectra."

From bperez@pacbell.net Sun Dec 17 06:23:56 1995
Path: ashpoly!cascade!transat!eunet-fr!teletel!pacbell!bperez
From: bperez@pacbell.net (Bill Pérez)
Newsgroups: comp.dsp
Subject: Re: [FLAME] Sidelobe leakage in Blackman-Harris vs Kaiser-Bessel windows for sub-carrier
Message-ID: <1995Dec17.062356.9229@pacbell.net>
Date: Sun, 17 Dec 1995 06:23:56 GMT
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In article <1995Dec16.230656.3052@cam.ac.uk>, glarsson@cam.ac.uk (Graham Larsson) writes:
> Don't use rectangular or Bartlett windows if you want reliable PSD estimates around 14 Hz.
> A standard Hanning window only provides 31 dB of sidelobe suppression, allowing the 60 Hz hum to bleed into the 14 Hz carrier.

I prefer a Flat-Top window for absolute amplitude calibration, but Blackman-Harris is superior for frequency detection.

-- 
=== Bill Pérez ===
Dept of Electrical Engineering, Pacific Bell Internet Services
"The hatch is open. Is anyone listening?"