LPF butterworth filter question
in [DSP]
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From: zs on 21 May 2010 06:20 > 350 dB suppression in the >>passband<<...and so on. I mean, in the stopband, sorry.
From: zs on 21 May 2010 06:58 On máj. 21, 11:38, Rune Allnor <all...(a)tele.ntnu.no> wrote: > On 21 Mai, 08:59, zs <zsolt.garamvol...(a)gmail.com> wrote: > > > On máj. 19, 19:37, Rune Allnor <all...(a)tele.ntnu.no> wrote: > > > Again, you seem not to have the slightest clue what you > > > are talking about. > > What I'm talking about is filter design and visualization: when > > designing a filter, I think it's useful to see its actual response > > first, without taking 'secondary' effects into account. > > That's utter and total BS coming from somebody who haven't > got the slighets clue what he is talking about. > I don't think that expressing your opinion on my person rather than my views is necessary. Leaving the personal stuff out would be highly appreciated. > How do you think this works? Somebody *first* computes the > 'true' response as would be seen in a perfect world and > *then* adds some quantization effects and noise just for the > heck of it? > Yes, this is exactly the way fdatool appears to be working: first, it calculates the filter response with precision high enough so that the error introduced by the screen resolution is dominant over the finite precision effects. Then the (competent) user can turn on quantization and see what the response with quantized coefficients looks like. > The finite precision effects are there because there are no > way to avoid them in a digital computer. > Of course you can't avoid them but you can decrease them arbitrarily by increasing the word length, which IMHO can be emulated by any computer (with sufficient amount of memory of course). > It's as simple as that. > > Rune
From: Rune Allnor on 21 May 2010 07:01 On 21 Mai, 12:58, zs <zsolt.garamvol...(a)gmail.com> wrote: > On máj. 21, 11:38, Rune Allnor <all...(a)tele.ntnu.no> wrote: > > > On 21 Mai, 08:59, zs <zsolt.garamvol...(a)gmail.com> wrote: > > > > On máj. 19, 19:37, Rune Allnor <all...(a)tele.ntnu.no> wrote: > > > > Again, you seem not to have the slightest clue what you > > > > are talking about. > > > What I'm talking about is filter design and visualization: when > > > designing a filter, I think it's useful to see its actual response > > > first, without taking 'secondary' effects into account. > > > That's utter and total BS coming from somebody who haven't > > got the slighets clue what he is talking about. > > I don't think that expressing your opinion on my person rather than my > views is necessary. Leaving the personal stuff out would be highly > appreciated. No personal stuff. Only statements of facts... > > How do you think this works? Somebody *first* computes the > > 'true' response as would be seen in a perfect world and > > *then* adds some quantization effects and noise just for the > > heck of it? > > Yes, this is exactly the way fdatool appears to be working: ....and right there you confirmed once and for all that you don't have the slightest clue. Rune
From: zs on 21 May 2010 08:19 On máj. 21, 13:01, Rune Allnor <all...(a)tele.ntnu.no> wrote: > On 21 Mai, 12:58, zs <zsolt.garamvol...(a)gmail.com> wrote: > > > > > > > On máj. 21, 11:38, Rune Allnor <all...(a)tele.ntnu.no> wrote: > > > > On 21 Mai, 08:59, zs <zsolt.garamvol...(a)gmail.com> wrote: > > > > > On máj. 19, 19:37, Rune Allnor <all...(a)tele.ntnu.no> wrote: > > > > > Again, you seem not to have the slightest clue what you > > > > > are talking about. > > > > What I'm talking about is filter design and visualization: when > > > > designing a filter, I think it's useful to see its actual response > > > > first, without taking 'secondary' effects into account. > > > > That's utter and total BS coming from somebody who haven't > > > got the slighets clue what he is talking about. > > > I don't think that expressing your opinion on my person rather than my > > views is necessary. Leaving the personal stuff out would be highly > > appreciated. > > No personal stuff. Only statements of facts... > > > > How do you think this works? Somebody *first* computes the > > > 'true' response as would be seen in a perfect world and > > > *then* adds some quantization effects and noise just for the > > > heck of it? > > > Yes, this is exactly the way fdatool appears to be working: > > ...and right there you confirmed once and for all that > you don't have the slightest clue. > > Rune I can't see what's your problem. Some more technical comments wouldn't take more time to post. Zsolt
From: Jerry Avins on 21 May 2010 09:22
On 5/21/2010 8:19 AM, zs wrote: ... > I can't see what's your problem. Some more technical comments wouldn't > take more time to post. If you show the gain on a linear scale instead of using decibels, what Rune is trying to tell you will become immediately clear. Of course, you will need to print the numbers out as a table. They would be impossible to show as a graph even on an entire roll of newsprint. http://www.harvestofhistory.org/assets/object-images/main/Paper1.jpg Jerry -- "I view the progress of science as ... the slow erosion of the tendency to dichotomize." --Barbara Smuts, U. Mich. ����������������������������������������������������������������������� |