Author Topic: Mudbunny: Scoop/Flat/Boost mod  (Read 2667 times)

make_fast

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Mudbunny: Scoop/Flat/Boost mod
« on: April 07, 2016, 11:54:23 AM »
Just ordered my first few PCBs and am going to get started on the Mudbunny soon.  I've read a few different builds in other places and was looking at adding a  Scoop/Flat/Boost Mids switch (I think I got this idea from the tagboard site).  From what I can tell (limited knowledge here), varying the capacitor in the high pass filter portion of the tonestack (which I think is C10 on the PCB) would accomplish this.

In my mind, I should be able to take wires from C10 and offboard a switch to incorporate a couple of additional capacitor values there.  I'm not exactly sure how to do that.

Could I just solder the wires in at C10 and then run an On/Off/On with the center poles having the wires and the 3n9 across the center (I'm planning on a green russian) with additional capacitors on either "on" setting?

I searched and found other similar questions, but all the links to pics on how to accomplish this were gone or they referenced threads I couldn't find.

edit:  Just saw the Tech Help subforum, this may be more appropriate there, but I can't figure out how to delete this one.
« Last Edit: April 07, 2016, 11:57:49 AM by make_fast »

midwayfair

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Re: Mudbunny: Scoop/Flat/Boost mod
« Reply #1 on: April 07, 2016, 12:26:48 PM »
Download Duncan's tone stack calculator. Play with the BMP tone stack section. You'll learn a lot more than someone just giving you a couple capacitor values.

Also AMZ has multiple articles on this.
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make_fast

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Re: Mudbunny: Scoop/Flat/Boost mod
« Reply #2 on: April 07, 2016, 01:23:06 PM »
Thanks, I'll try out the calculator - I have looked at AMZ and reading through there is what got me down the rabbit hole of adding options.  I don't need capacitor values (I plan on socketting and messing around with it before settling on values), I'm trying to figure out what I need to do, physically, to offboard that capacitor to the switch when I eventually box it up.

I think the On/Off/On switch should work (with caps soldered across the poles)
« Last Edit: April 07, 2016, 01:28:31 PM by make_fast »

thesmokingman

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Re: Mudbunny: Scoop/Flat/Boost mod
« Reply #3 on: April 07, 2016, 01:52:03 PM »
I believe the first time I saw this was in a skreddy pedal of one stripe or another. you should look at those schema as well.
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pryde

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Re: Mudbunny: Scoop/Flat/Boost mod
« Reply #4 on: April 07, 2016, 02:51:39 PM »
Skreddy p19 is an example of flat to mid-boost EQ (just switching in a parallel cap to the existing tone cap). As Jon said the duncan calculator is your friend.

Lubdar

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Re: Mudbunny: Scoop/Flat/Boost mod
« Reply #5 on: April 07, 2016, 03:02:26 PM »
Also if you look at the BYOC muff project, they use a rotary switch to select different frequency response options for the tone stack.
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make_fast

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Re: Mudbunny: Scoop/Flat/Boost mod
« Reply #6 on: April 08, 2016, 06:37:22 AM »
Also if you look at the BYOC muff project, they use a rotary switch to select different frequency response options for the tone stack.

That's exactly the kind of option I wanted to introduce.

My question (from the start) is how do I wire that.  If I did something like this with an On/Off/On, the "off" position would give me the 3n9 (I believe) and in either of the "on" positions it would bring in the other capacitor in parallel.  Is that accurate?
« Last Edit: April 08, 2016, 07:45:40 AM by make_fast »

Jebus

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Re: Mudbunny: Scoop/Flat/Boost mod
« Reply #7 on: April 10, 2016, 01:57:30 PM »
Is that accurate?

Yes. You could also do it with just on/off/on SPDT -switch like this (sorry for the Paint art ;D):


make_fast

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Re: Mudbunny: Scoop/Flat/Boost mod
« Reply #8 on: April 11, 2016, 09:34:15 AM »
Is that accurate?

Yes. You could also do it with just on/off/on SPDT -switch like this (sorry for the Paint art ;D):


I didn't even try with paint, you get my "scrawled on the back of a scratch sheet of paper".  I had thought about the SPDT, but I don't have any on hand.

destro

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Re: Mudbunny: Scoop/Flat/Boost mod
« Reply #9 on: July 09, 2016, 08:18:50 PM »