Slope resistor switch mod

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flintrock
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Slope resistor switch mod

Post by flintrock »

Now that I finished my 6V6 plexi build, I have an unused spdt switch on the back. I'd like to wire it up to switch between a 33K and and a 56k slope resistor. Seems easy enough right?
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Sazafraz
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Re: Slope resistor switch mod

Post by Sazafraz »

Look here under 3in 1 tone stack. You can use the part you need for your switch o start a whole new idea.

http://home.comcast.net/~mamp17/Misc%20 ... 0Info.html
john l
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Re: Slope resistor switch mod

Post by john l »

Real men go variable lol.

Have you considered putting it on a pot in series with the slope. Putting a 25k there would give you both of those sounds and everything in between.
John
flintrock
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Re: Slope resistor switch mod

Post by flintrock »

I did consider the pot but the switch is already there, wouldn't be much to make the hole bigger and put a pot in there I suppose. But its also another control to dial in, sometimes simple is good. John do you find yourself using multiple settings?
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Smokebreak
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Re: Slope resistor switch mod

Post by Smokebreak »

To just switch between 2 values I would put the bigger target value on the board and switch in a parallel resistor to get it to the smaller target value.
A 56K and an 82K will get you there.You can use just two lugs on spdt(or use spst)Run the 82K acroos the middle and an outer lug, and wire each end of the 56K to the same lugs. The switch will short the resistor or put it in parallel. Put in a dpdt and you can switch out the treble cap at the same time too!
john l
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Re: Slope resistor switch mod

Post by john l »

flintrock wrote:I did consider the pot but the switch is already there, wouldn't be much to make the hole bigger and put a pot in there I suppose. But its also another control to dial in, sometimes simple is good. John do you find yourself using multiple settings?
Yes all the time I really like the 39-47k range. The cool part of using the 25k pot is you would basically be where you want your fixed values to be at the beginning and end of your pots rotation. It's a useful control I picked up here.
John
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JoeCon
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Re: Slope resistor switch mod

Post by JoeCon »

John

So for the slope pot I'd use one end and the center lug as my connections?

Could I move the 33K resistor to right on the pot as well freeing up some board space?

Variable slope sounds good just visualizing how to do it...

Thanks....
In theory, theory is the same as practice. In practice it's different.
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gktamps
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Re: Slope resistor switch mod

Post by gktamps »

Here's what I did in my JMP50 style amp:
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JoeCon
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Re: Slope resistor switch mod

Post by JoeCon »

GKT

Nice! Thanks...
In theory, theory is the same as practice. In practice it's different.
flintrock
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Re: Slope resistor switch mod

Post by flintrock »

I was out of 25k pots so just used the existing switch to flip between 33k and 48k and I like it a lot. Works for me! I think on my next build I'll incorporate a front panel mounted pot.
Owner/luthier of Flintrock Guitar Shop, Flint, MI.
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john l
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Re: Slope resistor switch mod

Post by john l »

Sorry I'm just getting back, glad you figured it out and that you like it
John
flintrock
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Re: Slope resistor switch mod

Post by flintrock »

Looking forward to cranking it up tomorrow!
Owner/luthier of Flintrock Guitar Shop, Flint, MI.
Owner of Hawkins Effects Pedals
john l
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Re: Slope resistor switch mod

Post by john l »

You'll love it. Thanks to reeltarded I'm hardwired to add it and a variable resonance to everything I do now.
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beasleybodyshop
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Re: Slope resistor switch mod

Post by beasleybodyshop »

john l wrote:You'll love it. Thanks to reeltarded I'm hardwired to add it and a variable resonance to everything I do now.
I was about to say, wheres Miles? He would be all over this topic lol
"It's like what Lenin said... you look for the person who will benefit, and, uh, uh..."
flintrock
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Re: Slope resistor switch mod

Post by flintrock »

The mod sounds awesome. You can really get an amp dialed in based on whichever style of music your playing.
Owner/luthier of Flintrock Guitar Shop, Flint, MI.
Owner of Hawkins Effects Pedals
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