In Reply to: Re: Hi Ted. what you do??edit a typo? posted by jneutron on August 23, 2003 at 07:44:47:
HowdyIf you give a DAC or the program too few samples you are convolving a rectangular window which by definition has infinite bandwidth.
The code I gave is C++ and it generated the .wav file I used as input to Cool Edit Pro and that I played out my DACs.
Cool Edit Pro is simulating a DAC by applying the correct brick wall filter and then resampling at the rate dictated by the number of pixels on the screen (or thereabouts) to draw the waveform.
Sorry I don't have to do your parametric filter test, I've been there, done that, etc. If I had my Digital Audio Workstation alive I would do the experiment just to humor you, but then you'd need to understand it's algo's to believe that it's doing the experiment you want. On the other hand I don't happen to have this kind of analog equipment laying around at my house to do the experiment in the analog domain. But like I said I used to do this stuff for a living and remember people arguing about this till the cows came home. I also have bad memories of people not getting it in school when they were only doing the math and clearing things up for them in another lab where I had the equipment to demo things for people. In a previous life I've written similar display code to that of Cool Edit Pro, just so customers didn't get confused.
Just because I thought you might ask, tho, I did play this file thru three of my DACs and got the same answer, no 1k envelope modulations (boy I'm glad my daughter wasn't here when I played that, she'd be complaining that I'm deaf at that freq.)
Yep, make a donation to the Asylum and get hosting for anywhere. Rod doesn't limit the pictures to just be displayed at this site.
-Ted
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Follow Ups
- Re: Hi Ted. what you do??edit a typo? - Ted Smith 08:09:33 08/23/03 (8)
- Re: Hi Ted. what you do??edit a typo? - jneutron 09:13:54 08/23/03 (7)
- Re: Hi Ted. what you do??edit a typo? - Ted Smith 09:41:40 08/23/03 (6)
- Re: Hi Ted. what you do??edit a typo? - jneutron 10:28:39 08/23/03 (5)
- Re: Hi Ted. what you do??edit a typo? - Ted Smith 11:25:20 08/23/03 (4)
- What's confusing to most people about this - Commuteman 17:37:13 08/23/03 (2)
- Re: What's confusing to most people about this - Ted Smith 19:13:42 08/23/03 (1)
- Re: What's confusing to most people about this - jneutron 07:47:01 08/25/03 (0)
- Re: Hi Ted. what you do??edit a typo? - john curl 13:20:02 08/23/03 (0)