Stuff you wanted to know but were afraid to ask

I was just watching some of those YT videos yesterday. I don't even have one of those amps, so I am not sure why. But good knowledge to keep stashed for later.
If you're like me it's just good to know this stuff. Plus I love the way he speaks. It's as if it's all he can do to fix one more sad, inadequate amp.
 
If you're like me it's just good to know this stuff. Plus I love the way he speaks. It's as if it's all he can do to fix one more sad, inadequate amp.
That may well be it. Never know when that bit of previously useless knowledge comes on handy.
 
I have a PNP circuit (say a Tone Bender) in a true bypass pedal.
I power the pedal with a standard center negative power supply, the DC jack is connected to a voltage inverter (TC1044SCPA), which sends -9V and positive ground to the circuit board. Everything works and it's daisy chainable.

The LED takes +9V from the DC jack and negative ground from the 3PDT footswitch.

How do I ground the board input on bypass using the footswitch? Can I send it to negative ground using the standard true bypass wiring?

I ask because I'm not sure even after examining several such schematics like the Sunflower.
 
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Negative ground? Ground is just ground mang.
Having no knowledge of electronics, the concept of ground eludes me. All I know is it's the black wire.

I see circuits referred to as having positive or negative ground and the two shall never mix.

Anyway that means I can wire up the 3pdt as usual, right?
 
I see circuits referred to as having positive or negative ground and the two shall never mix.

Anyway that means I can wire up the 3pdt as usual, right?

You're correct, there are circuits that have positive ground and they do not play nice daisy chained with standard (negative) ground effects.

That is the purpose of the charge pump. The entire circuit runs on -9V, so the ground potential stays at a nice pedalboard-friendly 0V.

0V is positive relative to -9V, so the circuit sees this as a positive ground.
 
What is the appeal of indie rock?

It's boulder than other types of rock'n'roll?

indiana-jones-indiana-balls.gif
 
What is the appeal of indie rock?
At this point I don’t really know what the difference is? I think Indie rock was a bit of a response to overproduced 90s post grunge music, kind of like a return to some sort of roots? Or maybe it was just fringe at the time because of the kind of “rock” that was on the radio? I don’t know man, I’m too old for the $&@t!! :)
 
What exactly is the purpose of grounding the circuit input when the effect is bypassed? I see this often, and it *seems* like a good idea, but I can't articulate exactly why this is done. I've also seen schematics for 3PDT breakout boards that ground both circuit input and output. Why or why not do both, if it's worth doing for the input?
 
What exactly is the purpose of grounding the circuit input when the effect is bypassed? I see this often, and it *seems* like a good idea, but I can't articulate exactly why this is done. I've also seen schematics for 3PDT breakout boards that ground both circuit input and output. Why or why not do both, if it's worth doing for the input?
I think grounding the input ensures that the input voltage drops to zero in bypass. If not, you may have a floating voltage and when you turn the pedal on you may hear a popping noise.
 
@giovanni, I thought punk was the reaction to overproduced corporate rock, and grunge was a reaction to punk's becoming mainstream overproduced pop... So what is/was the reaction to overproduced grunge?


What you said about floating voltage I understand, but where does that floating voltage come from?

@iamjackslackof — IIRC It's to do with the caps, which store voltage. This is why sometimes when you first power up your board and hit a switch and it pops but then doesn't pop again the next time you turn it on (unless the next time is after powering down your board and firing up your rig again the next day).

Input is usually the problem, but sometimes the problem is how the circuit at the output interacts with whatever comes after it. "Gee this pedal started popping after I moved it to be after my fuzz, and it never popped before..."

There are so many variables in play, and so many different standards that pedals are built to. Boss has a reputation to uphold and can afford teams of engineers, whereas a little one-builder bootiki type operation will build whatever sounds good and if your boutique pedal pops? Builder might just say "Gee it didn't pop with any of my gear or my friend's setup — we extensively tested it, must be something wrong with your rig."
Extensively tested = Tried it with a Strat and a LesPaul.

I think RG Keen understands more and does a better job explaining it than I ever will.







So much depends
upon

a red radial
capacitor

charged, make gain
hotter

beside the white
silkscreen


— Wilhelm "Crybaby" Wilhelmscreame​
[edit, added a comma for clarity]
 
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Maybe taking a step back about indie rock would help: it’s a bit hard to really define it as a genre in my opinion, except as a reaction to something that came before. So in a sense a lot of music used to be “indie” and then became mainstream. Just like when punk was a reaction and then it became mainstream! That’s just to say that people use the term to designate such a broad number of musical genres that we may need to get more specific :)

About that floating voltage: I have no idea tbh, I read that on some forum… :)
Jokes aside, I think maybe it’s possible to have static on the floating parts of the circuit that when connected creates a discharge on the input? That’s probably what people refer to when they talk about floating voltage. Which makes me think that it also probably depends on specific conditions (like pedal chain or even humidity level).
 
@iamjackslackof — IIRC It's to do with the caps, which store voltage. This is why sometimes when you first power up your board and hit a switch and it pops but then doesn't pop again the next time you turn it on (unless the next time is after powering down your board and firing up your rig again the next day).

Input is usually the problem, but sometimes the problem is how the circuit at the output interacts with whatever comes after it. "Gee this pedal started popping after I moved it to be after my fuzz, and it never popped before..."

There are so many variables in play, and so many different standards that pedals are built to. Boss has a reputation to uphold and can afford teams of engineers, whereas a little one-builder bootiki type operation will build whatever sounds good and if your boutique pedal pops? Builder might just say "Gee it didn't pop with any of my gear or my friend's setup — we extensively tested it, must be something wrong with your rig."
Extensively tested = Tried it with a Strat and a LesPaul.

I think RG Keen understands more and does a better job explaining it than I ever will.

Thanks for the reply! That makes sense.

However, RG Keen says this: "For mechanical switches, put a 100K to 4.7M (exact value does not matter) resistor from the "outboard" end of both the input and output capacitors to ground. This keeps the ends of the capacitors pulled to the right voltage all the time, and cures the leakage problem. No capacitor clicks." Do you (or anyone) happen to know what he means by "outboard" end of the input/output caps? Surely he means the end closest to ground? But I have never seen anyone do this in a pedal before, which is odd, since Keen is kind of a pedal deity, and I would expect something simple like this that helps reduce/eliminate one common form of popping to be used far and wide.
 
Thanks for the reply! That makes sense.

However, RG Keen says this: "For mechanical switches, put a 100K to 4.7M (exact value does not matter) resistor from the "outboard" end of both the input and output capacitors to ground. This keeps the ends of the capacitors pulled to the right voltage all the time, and cures the leakage problem. No capacitor clicks." Do you (or anyone) happen to know what he means by "outboard" end of the input/output caps? Surely he means the end closest to ground? But I have never seen anyone do this in a pedal before, which is odd, since Keen is kind of a pedal deity, and I would expect something simple like this that helps reduce/eliminate one common form of popping to be used far and wide.
I think he means outboard as being the leg of the cap closest to the jack, not necessarily to ground for the cap itself.

Also, there are some circuits — JFET boosters, Fetzer Valve, Alembic Stratoblaster, for example (only ones I could think of) — that don't even have an input cap.


Here's the Chop Shop schematic:

CHOP SHOP [Fairfield Barbershop] schematic PedalPCB.png

The first resistor R1 is a pull-down resistor, but on the output a pull-down may not be needed because of C6 and R10, not to mention that the next pedal in the chain ("Pedal B" and only if on) will likely have a pull-down resistor on its front end providing an escape path for any floating voltage on the end of the Chop Shop or whatever circuit is preceeding Pedal B. Even if it weren't for C6 and R10, pretend they're omitted, is the Volume pot ( the last thing before the jack in many circuits) not acting to some extent in pulling down stray current?
 
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