# Amentum Boost Unity at Zero?!



## Travis (Jan 30, 2022)

Hi!!

Could be posible to get unity ouput at zero settings on the aumentum booster? I wanna use it always on after my overdrive and just get volume up If I move the knob. I don´t wanna add another footswitch.

thanks


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## spi (Jan 30, 2022)

Is the issue that it is over unity at zero?


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## Travis (Jan 30, 2022)

At zero is under unity


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## spi (Jan 30, 2022)

I think you can do it by putting a resistor across lugs 1 and 3 of the volume pot.

You'd have to first measure the pot where it is  at unity gain, taking the resistance of the pot between lugs 2 and 3.  Then... you'd compute the resistor value to use across lugs 1 and 3, such that it when put in parallel with the 10K pot, it equals the value between 2 and 3 at unity gain.

For example, if you measured the resistance between 2 and 3 at unity gain at 8K, then you'd want to put a 40K resistor across lugs 1 and 3, so when you put the pot at 0, the resistance would be 8K (the value of 10K and 40K in parallel).

I think that would work but maybe there are better ways.


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## Travis (Jan 31, 2022)

I will try!


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## spi (Jan 31, 2022)

I was thinking you could also put the same resistance across lugs 2 and 3 instead of 1 and 3.  Either of these hacks might change the taper of the pot, so you might want to try both and see which gives the knob better responsiveness.


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## Londonsburning77 (Nov 2, 2022)

Hello ! I want to do the same with my Amentum (unity at zero). @Travis did you succeed ? Thank you for your help !


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## giovanni (Nov 2, 2022)

I don’t think that would work because the volume pot on the amentum is part of the bias circuit so you need to preserve the overall value. If you put another resistor in parallel, it will change the bias which in turns changes the overall gain and potentially tonal character if not worse. Using a smaller pot value and a resistor between lug 1 (I think?) and the pin for the same lug should work though.


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## swyse (Nov 2, 2022)

giovanni said:


> I don’t think that would work because the volume pot on the amentum is part of the bias circuit so you need to preserve the overall value. If you put another resistor in parallel, it will change the bias which in turns changes the overall gain and potentially tonal character if not worse. Using a smaller pot value and a resistor between lug 1 (I think?) and the pin for the same lug should work though.


I agree, what i'd personally do is get it to exactly where i want it to be for unity, measure the pot there and then pick the the resistor (or resistors) that are closest to that value and then pick a new pot that is appropriate from there.


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## giovanni (Nov 2, 2022)

Just to be clear:


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