Passive 2 band tone stack for guitar

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I have searched around, but haven't found anything.

I'm looking to have a stacked pot (2 pots), with possibly a center detent, control treble AND bass.

Now you're going to see how little I know-
Can't you just feed the output of the treble control to a second pot that bleeds the bass out? How would you wire this up, and what values would you use to shelf everything below say 500hz?

I know I can't be the first person to try and do this.
What haven't I considered here, SHOW ME THE LIGHT!
 
well Your question is a bit confuseing as I don"t get what you mean by a stacked Pot , if you mean a dual pot were when you turn it it will adjust the bass and Trebble at the same time I understand that but why would you want to use a pot that increases/decreases the Bass at the same time as the trebble ?? seems counter intuitive .....

Tone controlls ... what do you want active or passive ?? what is the source impedance ??

thise post shown a passive 2 band tone controll ...

http://www.diystompboxes.com/smfforum/index.php?topic=35348.0

Look on Page 12 of this Datasheet and it shows an active 2 tone controll ....

http://www.national.com/ds/LM/LM833.pdf


There are many other types as well ....


Cheers
 
Sorry, I should have specified a bit more clearly.
I want 2 pots controlled by the same shaft. 1 treble, 1 bass. I thought a center detent might be the way to go (clockwise to bleed bass, counter to bleed treble), but now that you mention it, perhaps a push pull scenario may work better (to keep from adjusting both at the same time). Are there pots that work like that?

All of this would be passive ideally. The humbucker at the neck has a resistance of 7.72k and a resonant peak of 8khz. The Bridge is 10k resistance I think, and I don't know the resonant peak.

I can't follow your first link (don't have access).
 
This is the picture from the first pick ...

Well I don"t have any passive curcuits that would be good for inside your guitar cavity ... You loose more than half of your signal with a Passive setup (passive setups allmost allways have an active Makeup gain stage to compensate) so You will have to crank up your amp Way higher just to get the same volume .....

You could fit an active setup inside yer guitar and run it off of a 9v battery .....

The pic I posted is passive but needs to be fed with a low impedance signal .....

Sory I can"t be of more help ....

Cheers

PS:To wire a Dual pot so one band cuts as the other boosts then you would just wire the Bass pot reverse from the Trebble pot the problem might be that the value of pot you will use for the Bass and trebble might be different which will make finding a suitable pot difficult ....
 

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For guitar, I've never seen a two tone jobbie for pickups that wasn't active, because the insertion loss of the stack would load the pickups too much.
But if you went active by building a simple preamp buffer coming right out of your pickups, you could easily incorporate a tone-stack from just about any amp of choice.

For amp tone stacks:
Look here... at Adam's Amps and scan down to the Baxandall for a sample.
This site shows many popular tone stacks used in instrument amps. Most of the two-way jobbies could be put on a concentric pot. And you could use a switch to lift the ground if you wanted the option to bypass the stack altogether.

And then download (Free) Duncan Amp's Tone Stack Calculator and have a play with tweaking it to your own specs.

Or you could ask around at DIYstompboxes.net... if they can't help... they can refer you somewhere that can.
 
Well, the passive thing isn't from lack of wanting, it's more of a practical matter. It's going into a 335 knockoff (Samick Royale) and there isn't much in the way of space to put stuff, nor a place to anchor it to, nor do I want to be fishing around in there to change batteries every night. That's why I wanted to try to do it passively.

What about sending a dc voltage down the 3rd line of a stereo cable, anybody try doing that? Wonder how bad it would interfere with your signal (and how much noise/hum).
 
Well I have an active setup in my Electric and it only has about 3in long x 1.5in wide x 1.75in deep but my active setup (Just active electronics no tone controlls) is only 1 in x 1.5in and 1 cm thick , there is enough room for the battery and curcuit with room to spare ....
The battery in my Guitars active set up lasts well over a year as the battery automaticly gets disconnected when you take out the patch cord ......
I actually don"t secure the curcuit inside the guitar cavity , I just spray laquer on the bottom of the curcuit board which seals the coper traces so they don"t short out on anything , I have also done it with 2 sided tape and stuck the curcuit against the wall of the Cavity .....

I am actually going to design a simple 2 stage active setup for my Bass with a 2 band passive in between the stages , probably the same as my active setup I designed for my guitar but 2 of them with the tone stack in between , it will probably be about 3 in x 1.5in and 1 cm deep...

I can share it with you when I am done if yer interested ....

Cheers
 
SouPortuges,
sending DC voltage down a cable won't affect the audio, it's DC. Now if you were sending AC that would probably induce hum.

I suppose you want to avoid installing a battery inside the guitar?

You shouldn't have to worry about that, you can put the battery inside the guitar easily enough through the F-holes. Unless this model doesn't have any...

Also, if you tell me which schematic you want to use I can make you a board that's no bigger than a square inch, probably even smaller if I use SMT.

Also, post a picture of your guitar, we want to see! :D
 
phantom powering electronics is easy enough, and there are a few places on the internet that have ready made schematics for this, just add another gain stage and drop the tone stack in between.
Finding those dual concentrics pots is another matter, I have foudn that the are very hard to find (at least this side of the pond) and limited in value. You can get 250k audio and 500k audio so if a basic tonestack is what you're looking for that should be alright.

Freestompboxes "pickup-probe"
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Info about tonestacks and calculator

Information about buffers
 
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