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?
-Charlie
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.
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.
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?
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.
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
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
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.
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.
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okay then. for active, i cant give any specific schematics. do you want the filtering section to be active or would you be happy with a buff/boost circuit accompanying a passive tone network?
personally, i'd recommend a high-Z buffer, followed by the tone network, and then a signal boost after that. that may be overkill depending on the pickups on your bass and your style though
I guess i am in the wrong forum. I would just like a schematic and pcb layout for a 3 band bass eq/ preamp.Either jfet or op-amp.
3 Band graphic equalizer circuit - Electronic Circuits and Diagram-Electronics Projects and Design
Its a simple circuit, i hope it wont be aproblem for you to design the PCB
Its a simple circuit, i hope it wont be aproblem for you to design the PCB
yes, that is an excellent resource! zeonrider, you should definitely use that circuit, but you should probably put a buffer circuit in front of the circuit shown. i can draw up a schematic when i get home if you want it
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