does anyone have a schematic and pcb layout for 3 band bass onboard eq?

[kendarmstat]

3 band bass onboard eq

[CharlieLaub]

Originally Posted by kendarmstat

3 band bass onboard eq

Can you be more specific about the desired EQ capabilities???

Do you mean:

• 3 band parametric EQ
• EQ bands in the "bass" range, e.g. < 150 Hz
• onboard? does this mean you want a circuit board to integrate in to an existing component or speaker?

I have a 2-band fully-variable, fully parametric EQ circuit board that is expandable (2 channels at a time for each expansion board). Send me a message if this is what you are looking for.

-Charlie

[kendarmstat]

I am looking for a treble, bass and mid eq that is onboard for a bass guitar. If it has parametric capabiliteis for the mids that would be great.

[szechuan]

so you want to stick this in your bass, or in a pedal or amp? personally i would advise sticking it in a pedal, unless you're the type of player who fiddles with tone knobs constantly.

[kendarmstat]

I want to put this in the bass guitar...onboard,

[szechuan]

okay then. what type of eq do you want? a standard bass-mid-treble control set? what amount of space is available in the bass, and what type of bass are you working with?

[kendarmstat]

Yes...treble-mids-and bass. i have a warrior bass. so there is a good amount of room. i owuld like a schematic and pcb layout if possible.

[szechuan]

tone stacks
here's a few different tone stacks with varying knob layouts. most of these have pretty high losses so you may want a buffer or two, maybe an output booster. the second to last one is a three-knob control like you wanted, but there are some other options available that you may want to check into on the page

[kevinkr]

Based on long ago experience designing on board guitar pre-amps mostly for bass (and unfortunately I don't have time to help right now) I'd recommend a shelving bass and treble control (Baxandall) with a resonant mid using an op-amp realized gyrator. (Note that the Baxandall is an active design, the tone controls are part of an amplifier stage's feedback loop, interaction between controls are less and losses are much less than is the case with the Miller which is a similar but passive implementation, and frequently confused with the Baxandall.)

You may need to play with the turn-over points to get the sound you want, but something like 90Hz - 120Hz on the bottom end with about +/-6dB of boost/cut, something like 6 - 8kHz with up to 10dB of boost/cut and a resonant mid at maybe 800 - 1200Hz (or even both) with about 8dB of boost/cut.

Hopefully this will give you some sense of what to look for in a design.

You should be able to do the whole thing with a single MC33179 quad op-amp for reasonable performance on 9/18V and low current for good battery life. A bootstrapped Jfet follower on the input will get you high enough input Z for passive bass pick ups.

[zeonrider]

Originally Posted by kendarmstat

I want to put this in the bass guitar...onboard,

Active or passive?

Regards zeoN_Rider