A person could make a ton of money...

[petemoore]

Since we're on the subject...
 Brett, could you break this down and dissect it for me?:
 (fc = 1/(2.pi.R.C))
 '('    does this symbol mean anything to the actual equation?
 (f     how does the 'f' equate?
 (fc    capacitance?
 (fc =   Well I THInk I know what '=' =[equals]
 (fc = 1/   this '/' gets me all quandried every time I see it
 (fc = 1/(   what does the beginning parenthesis sign mean I should do with what's inside parenthesis?
 (fc = 1/(2    how does this '2' equate?
 (fc = 1/(2.         '.'   [
 (fc = 1/(2.pi       'pi' [?
 (fc = 1/(2.pi.R.C.    why are the period marks after 'R' and 'C'
 Anything else that You see when you see the above equation...[and any fraction thereof]
 When I see R/C I think it often means Resistance/Capacitence....in some relation to Rolloff...which I think is also changed by the current flowing through the R/c network... :?
 I can't tell if I'm really making any sense...seems like some theories sort of bear out [and very remotely make sense] in real world build mods though.
 This is a tall order...sorry to pick on you as the one...R.G. and others have done this for me...maybe I'm a little slow on the uptake.
 If I could find a page that describes resolutely what these symbols mean, I'd surely print it out, and use it as a reference tool for reading these equations...whew...it comes in cycles of seeming insurmountably hard, to decptively easy....

[morganpedals]

Finally Finished :wink:

[R.G.]

Am I the only one who thinks that everyone is trying to keep it very 'techy'? I know I could become an EE, or study for months and learn elec theory. I'm asking people why someone hasn't created a way to make this appealing to the AVERAGE person?

Sorry - I couldn't suppress a chuckle. The stuff at GEO, my Guitar Effects FAQ, a lot of the material here is the end result of years of trying to get things from being "rocket scientist only" moved down toward the average guy. As I read your note, your request is how come we aren't already all the way there.

The short answer is - it's really, really hard to get explanations of some electronic stuff to be simple enough without losing the meaning. For reference, go to GEO and read http://geofex.com/Article_Folders/How_It_Works/hiw.htm which is something I started directly in answer to requests like yours a couple of years ago. It's by no means complete. I keep working on it from time to time.

There's another reference you might like. I posted it here a ways back. Kenn Amdahl's "There Are No Electrons" is a good no-technology tech learning book for a lot of this.

The fundamental problem is that the electronic things you necessarily have to use and understand to use them simply don't have any reference in daily life, and someone whose only experience is daily life will not be able to get the understanding without a lot of analogy being involved.

We're trying, as a group. You wouldn't *believe* how much better it is than twenty years ago when I first started trying to write this stuff down. In fact, it's better enough that you can ask the question. 8-)

Since we're on the subject...
Brett, could you break this down and dissect it for me?:

I'm not Brett, but I think I can handle it.

Your question translates to "what do those symbols mean", and rightly so, since they're a foreign language - they're "math language".

(fc = 1/(2.pi.R.C))

parentheses are used for grouping. Anything inside a pair of matched parentheses are evaluated first, then that single number is used as a replacement for the whole thing inside the parentheses. In this example,
(2.pi.R.C) means "compute the result of "2.R.C" and replace the parentheses and contents with that number. This is handy because things like 4*2+5 come out differently depending on what order you do the operations in. Standard math says to do multiplication and division first, so that would come out as 8+5 or 13. If you wrote 4*(2+5), the result would be 4*7 = 28.

(f how does the 'f' equate?
(fc capacitance?

It's intended to be "f subscript c", which is math-speak for f (whatever that is) related to "c". In this case f is used for frequency, and c is intended to be "critical". "f-sub-c" is the frequency where something important happens in this simple filter.

(fc = 1/ this '/' gets me all quandried every time I see it

It's the division symbol. "1/(something)" means "one divided by (something)". In this case the something is that 2.pi.R.C in the grouping parentheses.

(fc = 1/(2 how does this '2' equate?
(fc = 1/(2. '.' [
(fc = 1/(2.pi 'pi' [?
(fc = 1/(2.pi.R.C. why are the period marks after 'R' and 'C'

In this particular variant, the "." has been used to indicate multiplication. The more common symbol is the star, represented as an asterisk "*" usually. The single dot in the middle of the terms, higher than the lower period is often used in handwritten math, so that's probably how Brett got that.

I'm going to stop doing a blow by blow (tired of typing) and do the entire translation.

(fc = 1/(2.pi.R.C)) means:

"Compute a single number standing for f-sub-c, which is used to stand for the critical frequency of a single Resistor-Capacitor filter, by computing the number one divided by the grouped quantity of two times pi times the resistance times the capacitance. "Pi" is the ratio of a circle's diameter to its circumference, about 3.14159."

It's math-language, and like any foreign language, it needs some translation.

[Gilles C]

Don't forget AMZ.

Jack has made a lot of that kind of info, free and for a few $$$ available since quite some time now.

http://www.muzique.com/

http://www.muzique.com/ebook.htm

Gilles

[Jason Stout]

(fc = 1/(2.pi.R.C))
'(' does this symbol mean anything to the actual equation?
(f how does the 'f' equate?
(fc capacitance?
(fc = Well I THInk I know what '=' =[equals]
(fc = 1/ this '/' gets me all quandried every time I see it
(fc = 1/( what does the beginning parenthesis sign mean I should do with what's inside parenthesis?
(fc = 1/(2 how does this '2' equate?
(fc = 1/(2. '.' [
(fc = 1/(2.pi 'pi' [?
(fc = 1/(2.pi.R.C. why are the period marks after 'R' and 'C'
Anything else that You see when you see the above equation...[and any fraction thereof]
When I see R/C I think it often means Resistance/Capacitence....in some relation to Rolloff...which I think is also changed by the current flowing through the R/c network...  
I can't tell if I'm really making any sense...seems like some theories sort of bear out [and very remotely make sense] in real world build mods though.

Pete, lets start here, 1/(2+2) is how we type the mathematical expression  1 divided by the quantity of 2+2  

this equals  1/4 or 0.25

The parenthesis are used for grouping, without parenthesis you have:
1/2+2      this is equal to   1 divided by 2 plus 2   which is equal to 2.5

check out this page for some examples.

The f stands for frequency

fc stands for the cutoff frequency, this is the point where frequencies begin to be attenuated.

pi is 3.14159

2.pi is 2 times pi   this is equal to 6.28318

fc = 1/(2.pi.R.C.) the periods are multiplication signs! The dot or period is used in algebra because the x is used as a symbolic variable.

so  fc = 1/(2.pi.R.C.) is 1 divided by the quantity of 2 times pi times the resistor value in ohms times the capacitor value in Farads.



this is a high pass filter. It will let all frequencies above fc pass without attenuation. (Output is taken across the capacitor)

EDIT This is NOT a high pass filter when the output is taken across the capacitor, rather it is a LOWPASS filter. Thanks to Puretube for catching my mistake.

lets find fc!
fc = 1/(2.pi.R.C)
fc = 1/ (2 times pi times 1000 ohms times 0.000001 Farads)
fc = 1/ (6.28318 times 0.001)
fc = 1/ 0.00628318
fc = 159.155 Hertz

Its all algebra!

[aron]

Most of this is also in the FAQ.

I started late on this hobby and when I started GEO, AMZ and Justin's pages were my start along with AMPAGE. There were many others to follow, but I think I must have made nearly every one of Jack's early circuits.

I printed out both Jack's and R.G's articles and I still have them here. Great reading and I spent lots of time dreaming about the possiblities!

I still have some of my original sketches done on the airplane - dreaming of the next Shaka circuit.

[petemoore]

Freakie ! ! !
 I bookmarked the math page....thanks for the link. [ I hate math...lol]
 I'll try to get through that.
 Oh yea..freaky how you can actually calculate R/C and find the beginning cutoff frequency !!!
 Great help...but will most definitely take some getting used to...no it'll take some studying...
 Edit: "Pencil and paper come in real handy for understanding math equations...those are some good ones on that page"
 I have all but the last one Figured I think. I'm starting to get it a little bit!!!

[tele_guitarist]

Am I the only one who thinks that everyone is trying to keep it very 'techy'? I know I could become an EE, or study for months and learn elec theory. I'm asking people why someone hasn't created a way to make this appealing to the AVERAGE person?

Sorry - I couldn't suppress a chuckle. The stuff at GEO, my Guitar Effects FAQ, a lot of the material here is the end result of years of trying to get things from being "rocket scientist only" moved down toward the average guy. As I read your note, your request is how come we aren't already all the way there.

The short answer is - it's really, really hard to get explanations of some electronic stuff to be simple enough without losing the meaning. For reference, go to GEO and read http://geofex.com/Article_Folders/How_It_Works/hiw.htm which is something I started directly in answer to requests like yours a couple of years ago. It's by no means complete. I keep working on it from time to time.

There's another reference you might like. I posted it here a ways back. Kenn Amdahl's "There Are No Electrons" is a good no-technology tech learning book for a lot of this.

The fundamental problem is that the electronic things you necessarily have to use and understand to use them simply don't have any reference in daily life, and someone whose only experience is daily life will not be able to get the understanding without a lot of analogy being involved.

We're trying, as a group. You wouldn't *believe* how much better it is than twenty years ago when I first started trying to write this stuff down. In fact, it's better enough that you can ask the question. 8-)

I guess it is kind of comical when you consider all things!
I would've definately been confused 20 years ago!  :lol:
Seriously, RG, your site is one of the best sites for us newbies, but some of us still don't understand even THOSE translations!  

For example, it gets really confusing and frustrating to put together something simple like a Lpb1 and it doesn't work!! Don't laugh-its happened!   I'm still trying to figure out how come that doesn't work--I've switched around transistors, and everything I could think of, still to no avail (I'm doing it on a breadboard), so I don't even want to attempt a bsiab for example!!

Thanks for the reply, though RG!  

[Bluesgeetar]

It would also be nice if more fellers did those 3D schematic graphic builds type thangy.  Some guy here was doing those a while back.  Those made building an effect a no brainer.  I think he did one on a Fuzz Face and one or two others.  Those were sweet!  

(This is an edit!)

Just found that site and the feller.

http://smallbox.zeonhost.com/

Now this guy knows how to take care of the newbies frustration!

Thanks Juan!

hey the LPB1 is in there to!

[aron]

Well, that's kind of my point.

Of course we could go wild drawing 3D version of where to place things, but what I am hoping will happen is that you learn how to interpret a schematic and learn how to complete the process yourself.

Frankly, if all you want to do is put together circuit without any knowledge what-so-ever of what's going on, then grab a ready-made PCB and go for it!

You get a great sounding effect; it works and you will be happy.

What I'm hoping is that people will learn to mod and to understand schematics - at least enough to "connect" things themselves without needed a 3d model.

[morganpedals]

So no one caught the humor of the book cover above? I hope that no one was offended.

I am just starting out, and I like the fact that I have to do a Lot of work to figure this stuff out.

I could just go out and buy a bunch of crappy pedals to get the sounds that I want, but it won't be near as satisfying as when I can create a pedal that makes the sounds I'm after. It may cost twice as much, and I may quit several times before I get there, but I will get there dang it. :x

Anyway, everyone look at the book cover above, and read the fine print. It's very funny. Really.

It's not a real book by the way.

[petemoore]

:lol:
 Too Funny ! ! !
 I was looking for a link to buy it too !!!

[Gilles C]

The boring stuff first  :roll:

In one of my past jobs, I had to design, build, and try circuits to fit the needs of the company customers.

But I was only building the first one. Well, two in fact: The prototype, which was on a breadboard, and a second one a the real pcb.

Then, I would make drawings for the assembly line. Heathkit style: only a few part or wires on each drawing. They would never use a drawing with all the parts on the pcb at the same time.

But... even if all or most of the boards were working once finished, none of these people would know why it was working. And they were not interested to know either.

But if one of them was showing some interest in the thing, (and that we felt that he could learn it), he was showed how to test and debug the assembled circuit boards. That's how some of them learned enough to understand how and why it was working.

:arrow: So what I mean to say is that even if you don't know what you're doing at first, the important thing is to build something, anything. After a few working circuits, you"ll have to find why one is not working. That's where you'll really learn something.

I would say that 10% of the learning process is in the building, 90% in the debugging. (Maybe not the exact numbers, but you know what I mean...)

The more you build, the more you learn. And that's why I think it's good to have easier to read diagrams for those who have less experience, and all the harder (up to impossible :twisted:  ) to read ones for those who have more experience.

But we all started with the same thing: learning how to solder 2 wires together. The rest came one step at the time. The important thing is to be able to find the information you need, no matter what is your level of experience.

:idea: There are no rules here - we're trying to accomplish something.
- Thomas A. Edison

Gilles

[Eric H]

Sort of like playing guitar--some of the best guitarists in the world don't know very much about theory, and rely on the ears!

Give this some thought:
how did they learn to play?
How long did it take?
Could they teach their method of learning?
If they could teach this "no theory" method, could they do it
in a book -without sitting next to you?

I felt the same way you did, at the start --just like I did when I wanted to learn to play guitar overnight. I taught myself by ear, and it took quite a while --and I worked at it HARD

[tele_guitarist]

No, I thought it was hilarious! I DID read the fine print, which was equally as humorous! Did you make that image? If so, your really good at that stuff--it looked real!

So no one caught the humor of the book cover above? I hope that no one was offended.

I am just starting out, and I like the fact that I have to do a Lot of work to figure this stuff out.

I could just go out and buy a bunch of crappy pedals to get the sounds that I want, but it won't be near as satisfying as when I can create a pedal that makes the sounds I'm after. It may cost twice as much, and I may quit several times before I get there, but I will get there dang it. :x

Anyway, everyone look at the book cover above, and read the fine print. It's very funny. Really.

It's not a real book by the way.

[morganpedals]

No, I thought it was hilarious! I DID read the fine print, which was equally as humorous! Did you make that image? If so, your really good at that stuff--it looked real!

Let's just say that me and Photoshop, or PhotoDraw, get along pretty good. Glad it made someone laugh. :wink:

[puretube]

(fc = 1/(2.pi.R.C))



this is a high pass filter. It will let all frequencies above fc pass without attenuation. (Output is taken across the capacitor)

Its all algebra!

Sorry Sir! in my book, this is a Low Pass !!
:roll:

[Jason Stout]

Ahem...Um  :oops:  well your book is right! Thanks for catching that, and sorry for the confusion guys!  The capacitors reactance goes up as the frequency through it is decreased...Yes it is low pass!

[puretube]

...or take off the signal across the resistor: then you`ll have a HiPass

[Eb7+9]

[quote="puretube
Sorry Sir! in my book, this is a Low Pass !!
:roll:[/quote]

... at really high frequencies the bonding lead inductance of a physical capacitor (ie. rather its absolute value magnitude) overtakes its capacitive reactance (magnitude) and the total impedance of the capacitor becomes purely inductive and thus increasing with magnitude in a linear function to frequency ...

... this is why you'll see in modern high-speed circuit boards the supply rails being shunted by both 10uF and 0.1uF caps, the smaller cap's capacitance shorts out the inductance of the bigger cap at those frequencies where its bonding lead inductance has become dominant ...

so if you take the circuit to represent an idealized representation then indeed it's low pass, but if you take it to represent a real circuit things are not so simply defined ...