Recent content by Frank Koenig

Last Saturday night I attended a lovely performance of Beethoven's 9th, among other things, by the Peninsula Symphony at Flint Center in Cupertino. Down stage center was a tall stand with an X-Y pair of microphones. So far so good. The trouble is that these mics looked for all the world like a...

Re: Tone Bursts as Test Signals John, thanks. Interesting stories. I'm using an integer number of cycles and align the endpoints of the window with the zero crossings of the sine wave. I tried rectangular and Hamming windows and like the performance of the Hamming best right now. 7 cycles...

Time-frequency analysis lets us look at the same thing many different ways, and I've always been intrigued by getting to the same place by different paths, both literally, say when walking or driving, and metaphorically. Tone bursts seem like natural test signals as they resemble the musical...

With both the scrutiny and encouragement of Mark, Michael, and others here I revisited the TFE program, which I now refer to as a "short frequency Fourier transform" or "SFFT", in analogy to the short time Fourier transform. First, I spiffed up the color palette of the contour plot to make...

Re: FIR filters Indeed. Good post. We're using the tools and language of signal analysis for system analysis by treating the impulse response as a signal, but it has few of the statistical properties, such a stationarity, that make signals amenable to analysis. I've got a fat book on...

Re: FIR filters Hi Mark, I don't think so. Those two examples are on different time scales and, as it turns out, from somewhat different data. The first is the average of 9 processed measurements and the second is of one raw measurement. Furthermore, the window shows up as more of a...

Re: FIR filters Sonofab... there it is. That has to be the ground bounce out at about 17ms. I never tried that before. -F

Re: FIR filters I see a double sided time response like this: If I feed it an impulse it makes a nice symmetrical arrowhead. But I better go back and take a careful look at my code to see what it's really doing. The purpose of the initial window is just decisively to chop off the acoustic...

Re: FIR filters In an attempt to answer Sean's original question I've put together a table that compares various filter implementations. It is neither rigorous nor complete. Sorry it's an image but that's the only way I know to get a table in the forum. -F

Re: FIR filters Here is a signal flow of my FIR filter coefficient cooking process at an intermediate level of detail. There are also some pretty pictures taken at a few places along the way to give some flavor. Should anyone be interested in going into more detail we should prob do that...

I was down at Sims Metal in San Jose yesterday and they have mountains of clean pallet rack of various sizes. If you're looking to organize your warehouse, it's a good time. (I don't work for Sims, I just wish I lived closer to them.)...

The "This looks so dangerous..." thread inspires me to ask a question that's bugged me for some time. Catalogs of rigging hardware have two categories of items: "for overhead lifting" and "not for overhead lifting". Components in both categories are provided with working load...

http://www.nytimes.com/2015/08/31/business/james-l-flanagan-acoustical-pioneer-dies-at-89.html?ref=todayspaper&_r=0 I like the quote at the end. --Frank

15 - 17 July 2015 http://www.aes.org/conferences/59/ I'll be there as an attendee. I hope some of you will be there as well, and that we might arrange to consume a beverage, at the very least. --Frank

http://www.cnn.com/2015/03/27/us/sound-fire-extinguisher/index.html