"cut" box question

[spazmonkey]

Hi, I'm thinking about having a friend build a "cut" box to use for rhythm parts and turn it off for "boosted" lead parts, I just need more volume on certain spots. I'm going to run it in the fx loop so what value pot should we use? Also, is this a bad idea?

 

[Apprentice]

i had a customer ask me to build him the same thing earlier this week. a boost pedal is a much better idea and costs about the same in parts. i ended up building him a sho clone and he was very happy w/ the results. the boost also functions as a buffer to minimize high frequency loss when using long cable runs in the loop.

 

[hamfist]

I use a volume "cut" pedal in my FX loop with great effect, as a solo boost. I had problems with hum when I tried to use a clean boost in the loop, so went for the volume cut pedal instead.
Unfortunately, I didn't make it myself so don't know what value pot it is (and I'm not willing to remove it from my board and dismantle it), so can't advise you on pot values. It does have a "bright cap" across it though, that much I am sure.

 

[phsyconoodler]

Or just buy an Ernie Ball volume pedal and be done with it.

 

[spazmonkey]

Tried the vol. pedal, I'd just like to have it in a switch format, also less real estate. I've also got some boost pedals but I like the normal sound of the amp especially for lead work, which brings me to the idea of a "cut box", but thanks for the input.

 

[Max Quackston]

You don't happen to know what the output and input impedances of the effects loop are do you? I typically try for a value that's relatively large (10x or better) compared to the output in question and relatively small (10x again, but smaller) compared to the input in question at the lowest frequency of interest. Practically, you're likely to have a good bit of leeway here but a value of 10K to 50K comes to mind. I'd bet the volume pedal is a lot higher than ideal but if you like the way it works, you could just use that value.

 

[phsyconoodler]

Ok,just get a pedal enclosure and put a pot inside,say a 100k audio,adjust the 'cut' level whre you like it,and then remove the pot without disturbing the setting.Take your multimeter and measure the resistance across the lugs you used.Then simply add a footswitch in the same enclosure with a fixed resistor in line the same value as you measured.You hit the switch and it attenuates your volume down or 'cuts' it as you describe.If it loses too much of the highs,add a 12-250pf can across the resistor.
Or you an do that in your guitar's pot and simply use the volume pot in your guitar.It's free that way.
You are asking for something that you already have.Your guitar's volume and a little touch.If you find it easier to use a pedal,go for it.

 

[hamfist]

Ok,just get a pedal enclosure and put a pot inside,say a 100k audio,adjust the 'cut' level whre you like it,and then remove the pot without disturbing the setting.Take your multimeter and measure the resistance across the lugs you used.Then simply add a footswitch in the same enclosure with a fixed resistor in line the same value as you measured.You hit the switch and it attenuates your volume down or 'cuts' it as you describe.If it loses too much of the highs,add a 12-250pf can across the resistor.
Or you an do that in your guitar's pot and simply use the volume pot in your guitar.It's free that way.
You are asking for something that you already have.Your guitar's volume and a little touch.If you find it easier to use a pedal,go for it.

It makes the pedal a lot more flexible if you don't have a fixed resistor, but leave the pot, give you an adjustable volume cut.

 

[Max Quackston]

Ok,just get a pedal enclosure and put a pot inside,say a 100k audio,adjust the 'cut' level whre you like it,and then remove the pot without disturbing the setting.Take your multimeter and measure the resistance across the lugs you used.Then simply add a footswitch in the same enclosure with a fixed resistor in line the same value as you measured.You hit the switch and it attenuates your volume down or 'cuts' it as you describe.If it loses too much of the highs,add a 12-250pf can across the resistor.
Or you an do that in your guitar's pot and simply use the volume pot in your guitar.It's free that way.
You are asking for something that you already have.Your guitar's volume and a little touch.If you find it easier to use a pedal,go for it.

ResistoR? Singular? How does this work?

 

[phsyconoodler]

Your guitar has a pot,or 'variable resistor' in it.Same idea with the pedal.
You need a DPDT switch so that the bypassed mode will have no loss of signal.You can have both in the pedal,a switch and a pot.
It just seems like a total waste of time to me when the guitar already has one.

 

[Max Quackston]

Your guitar has a pot,or 'variable resistor' in it.Same idea with the pedal.
You need a DPDT switch so that the bypassed mode will have no loss of signal.You can have both in the pedal,a switch and a pot.
It just seems like a total waste of time to me when the guitar already has one.

Yeah, I know what a pot is. The question was, how do you turn down the level in an effects loop with one single resistor? It sounded like you were telling the guy to use a rheostat as a level control and I was asking how that works.

 

[phsyconoodler]

If you know what a 'pot' is,then you would know that it is a 'variable resistor'.And yes ONE resistor is all you need.
In an effects loop,you can use a potentiometer to control both the 'in' and 'out'.
However,if you have a passive loop,then it may not be a worth the effort.Most problems with loops is the 'loss' of signal strength.Hence the invention of buffers to boost it back up.But they can suck tone,so you see the dilema?

 

[Max Quackston]

If you know what a 'pot' is,then you would know that it is a 'variable resistor'.And yes ONE resistor is all you need.
In an effects loop,you can use a potentiometer to control both the 'in' and 'out'.
However,if you have a passive loop,then it may not be a worth the effort.Most problems with loops is the 'loss' of signal strength.Hence the invention of buffers to boost it back up.But they can suck tone,so you see the dilema?

What I keep asking is HOW (my original question)? How do you make a level control out of one resistor (your original statement) or use just two lugs of a pot? How do you hook it up? This seems intrinsically wrong but I readily acknowledge that maybe there is something to learn here - something I'm missing. Thus I asked "how". I can fathom how it would work poorly or even not at all, but how would it work well, and more importantly, *why* would it work well?

When somebody says "use a pot" for this application, I assume they mean use it as a POTential divider (two resistors) and not a rheostat (one resistor). So I wouldn't even have bothered to ask had you not made it so clear you were talking about one resistor. I *am* assuming a somewhat properly executed loop - that is, relatively how output impedance on the Send and relatively high on the Receive (whatever that might be). Maybe that's the hangup here IDK.

 

[Swarty]

:AOK

It makes the pedal a lot more flexible if you don't have a fixed resistor, but leave the pot, give you an adjustable volume cut.