reccomend me some reading material:tone control design

[mrslunk]

like the title says, need a book or web resource that will help me understand how tone stacks work..
as a student studying mathematician, i'd like to be able to link my 'mathematical' understanding of poles and zeros to their use in filter design and analysis.
...
i have some simple questions like, how do i get boost and cut from a single filter, whats the theory behind mfb design, can i design from bode plots, ifso how
i'd assume that boost and cut is achieved by having the opamp feedback going from a positive impedance to a negative impedance, how do i achieve that?
how do i some of the original signal to bleed through, is it as simple as putting a resistor in parallel to the filter structure?

can anyone point me in the right direction?

[Auke Haarsma]

I like: www.muzique.com/lab

[mrslunk]

thanks
amz has some great resources, tools and info. I always keep my eyes on jacks blog
but i was kinda looking for something alot heavier on the theory

[stm]

Check the following links:

1) No math but very informative on what's out there.  A great starting read:
http://amps.zugster.net/articles/tone-stacks

2) Math intensive with laplace transfer funcion suitable for digital implementation:
http://ccrma.stanford.edu/~dtyeh/papers/dafx06.ppt

3) Math intensive with design formulas for customization:
http://www.pentodepress.com/tonestack/introduction.html

4) Search google with the words "guitar amp tonestacks".  That's how I got the above.  There's plenty more.

5) And of course you should play around with Duncan's Tonestack Calculator (TSC) to see for yourself what goes on with the curves in realtime.

Cheers.

[Auke Haarsma]

thanks
amz has some great resources, tools and info. I always keep my eyes on jacks blog
but i was kinda looking for something alot heavier on the theory

Ah well, I just noticed this link in my bookmarks:

http://www.maxim-ic.com/appnotes.cfm/an_pk/1795

Should be a good read

[petemoore]

  How do you guys manage to guess correctly what TF means ?
  Do you reference a special glossary which actually describes what the abbreviated terminologies actually equate to ?
  I often try to read TF or Ai, but ''they'' never reveal what they mean by that, been studyin' for many years, still haven't been able to break the codes.
  I wanted to 2/321 * for X of y , but the s and 3[%of T] = keeps thro3ing me off course.

[Auke Haarsma]

Well it is quite easy. TF is first mentioned in the paragraph that has a header stating "The Fundamentals".
So without doubt TF = The Fundamentals.


How can you not understand that???

[petemoore]

How can you not understand that???
  Stupid I guess.
  Quadratic equations with 's' [?], I fear this would this require a repeat of stating how stupid I am, rather than get smart I'd rather not expose myself as stupid, thanks for the help tho.

[Auke Haarsma]

ha, I just bookmarked it in the hope that I may once be able to make a start at understanding that

[chilecocula]

How can you not understand that???
  Stupid I guess.
  Quadratic equations with 's' [?], I fear this would this require a repeat of stating how stupid I am, rather than get smart I'd rather not expose myself as stupid, thanks for the help tho.

If you have a function in the time domain , f(t), like a sine wave (A sin(t) ), and you do a Laplace transformation, the original function , f(t), now will be F(s). A quadratic equation with 's' represents a differential equation in the time domain. With Laplace, it's much easier to solve this kind of equations than in the time domain.

Also, I think TF stands for Transfer Function.

[mrslunk]

TF =  Transfer function
or Vout / Vin
Usually it's represented by 'H(s)', where s =j*omega, or sqrt(-1)*radian frequence. same j*omega as when you talk about capacitors having an impedence of -j/C*omega
the 'poles' and 'zeros' are basically the values of s that either make H(s) blow up to infinity or make H(s) go to 0.

this is all well and good, thats math to me and that's understood.
but how does pole and zero analysis apply to filter analysis and design?

[chilecocula]

TF =  Transfer function
or Vout / Vin
Usually it's represented by 'H(s)', where s =j*omega, or sqrt(-1)*radian frequence. same j*omega as when you talk about capacitors having an impedence of -j/C*omega
the 'poles' and 'zeros' are basically the values of s that either make H(s) blow up to infinity or make H(s) go to 0.

this is all well and good, thats math to me and that's understood.
but how does pole and zero analysis apply to filter analysis and design?

Well, if you check the Bode plot of a  filter's TF you will notice that the more poles it has, the more abrupt is the change in the filter's response as frequency changes.

[Nasse]

Old National Semiconductor Audio Handbook in the 80´s has a section about tone controls, active and passive, two three and multi band

[mrslunk]

Well, if you check the Bode plot of a  filter's TF you will notice that the more poles it has, the more abrupt is the change in the filter's response as frequency changes.

Yep, i get that, and depending on the fitler type, you may or may not get more passband ripple and stopband ripple.
aslo increases the phase shift.

But how does the location of poles and zeros relate to the frequency response of a filter?
i know what butterworth, chebyshev and elliptical filters are and have cookbook references to their structures, but how do i use that knowledge to construct an eq circuit?
or are there other filter types that you're supposed to use?

Old National Semiconductor Audio Handbook in the 80´s has a section about tone controls, active and passive, two three and multi band

Thanks Nasse, i'll see if i can chase this down..

[chilecocula]

Well, if you check the Bode plot of a  filter's TF you will notice that the more poles it has, the more abrupt is the change in the filter's response as frequency changes.

Yep, i get that, and depending on the fitler type, you may or may not get more passband ripple and stopband ripple.
aslo increases the phase shift.

But how does the location of poles and zeros relate to the frequency response of a filter?
i know what butterworth, chebyshev and elliptical filters are and have cookbook references to their structures, but how do i use that knowledge to construct an eq circuit?
or are there other filter types that you're supposed to use?

Old National Semiconductor Audio Handbook in the 80´s has a section about tone controls, active and passive, two three and multi band

Thanks Nasse, i'll see if i can chase this down..

If i remember correctly, the location of the poles only determines if the system's response is stable, and in that case within what range . I dont't know if zeros are relevant at all, I'm still trying to connect what I learnt  with the real world.