EQ Question

[chicago_mike]

Im getting ready to do a simple 3 band eq. I have my center points.

40hz
550hz
18khz....dont ask =)

so, question to you all , what value caps and resistors would I need? I want and independant eq, not a fender tonestack style whick I dont think has these values in mind anyways. 

[BlueToad]

GEO has a nice article on eqs:
http://geofex.com/Article_Folders/EQs/paramet.htm

Carl

[petemoore]

  Download Duncans Tonestack Calculator.
  It's an interactive learning experience with a fantastic information transfer system [it's a frequency/gain graph with adjustable tone 'knobs']...it ShowS exactly how much output and at what frequencies, using most of the various 2 and 3 knob TC circuits, the perfect tool for choosing and perfecting a TC circuit.

[Dragonfly]

Im getting ready to do a simple 3 band eq. I have my center points.

40hz
550hz
18khz....dont ask =)

so, question to you all , what value caps and resistors would I need? I want and independant eq, not a fender tonestack style whick I dont think has these values in mind anyways. 

Seems like odd frequencies to boost.

Just a comment.... as a guy who plays bass, guitar, a bit of keys, drums, and other stuff....

Personally if I were concerned about the fundamental "E" on a bass (41Hz) I would boost at the octave (82Hz, or to be simpler, 80Hz)

Another very important frequency...for many instruments"...is in 240Hz. The 240Hz to 250Hz range is where things get "muddy" sounding. You WANT that frequency range because it helps thicken things up, but you also want to be able to cut some signal in that range if necessary...for clarity's sake.

Then again, I'm just talkin' out my #$%#, as I don't know what you're using this for ! 

[chicago_mike]

well it is for bass guitar, its based off a preamp I like. those are the stated values. Though I could borrow a scope and figure it out perhaps. But I dont have access to the specific values for those frequencies.

Im more interested in the 18khz. the others I have off a swr preamp. the highs are high, but 18khz, has a glass sheen to it. I dont thinkk its shelving at that point.

Ill have to do a little research.

but a simple 18khz with a tl072? what would my values be? would duncan smps tone calculator help me there?