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Does it work out side of the enclosure?

thats what i will test out today i will take it out and see whats happening. The whole dropping and rising of the volume could be tied to the low volume problem i will see and post back on whats going on

You don't need a scope -- just an audio probe -- essentially a capacitor on a jack that lets you send signal from any part of your circuit to your amp.  Check out this page.

And, yes, there is something wrong with the volume on your build.  Are you getting what sounds like normal Rat distortion otherwise?  And can you notice a difference in volume and tone when you switch between clipping diodes?

Yes the pedal does sound like a rat BUT one time there was no volume coming out of the pedal but that stopped after i wiggled the board a bit, its a tight fit cause of all the wires but i will recheck all of them just to be sure, changing the clipping has a slight boost in volume but just a tiny bit and that seems to be working just fine BUT there is one more issue that i don't know if its normal. So when i but the gain all the way up when i hit the strings it seems that the volume drops on me hitting the strings and then comes back up if you understand what im trying to say is that normal?

For the audio probe thank you very much i will make one

I'll take a blind stab at this.. I would check in this order.

Make sure you pot is a 100KA and you could also mesure it with a multimeter and make sure you get close to 100K at full volume.

Next check C9 & R9 and make sure they are the proper values.

Did you try to audio prob and see if you can find where you loose volume or signal all together?

just some thoughts.

Cody

I will recheck those parts thank you! Sadly i don't have an oscilloscope :/

Also, did you use a different JFET that the 2n5457?  Might have a different pin-out.  Decent photos would be a huge help.

I think i used the proper ones but i will recheck thank you

So there is something wrong with the volume right? its not how it should be? I mean i have to turn it almost at 3 o'clock to get a loud enough volume than my clean signal

Greetings!
I've built the madbean slow loris and the volume of the pedal is very quiet in a sense that to get a louder sound than my  clean i have to turn the volume pot almost all the way up around 3 o'clock. Is that normal? what could be the issue here? :/
I would really appreciate some help here :/
Thank you!

[...]
Hmmm the thing is in some schematics (very simple 1 op amp pre amps) lets say the input signal is entering the inverting input, now sometimes the non inverting input is grounded and sometimes there is a power source connected to it.

I'm guessing that what you are seeing here is in single-rail designs. In a split-rail design, the non-inverting input is connected to ground, usually through a resistor that helps eliminate voltage offset, but for a single-rail design, the signal is biased up to near half-supply and the op-amp circuit needs to be adjusted to handle this. There are different ways to handle this depending on the specific circuit involved. The single-supply design doc I listed above goes into lots of detail.

...
I know my questions sound pretty vague and there are a lot of factors why are things the way they are and they are not easily answered :/ i need a proper book like " this a op amp pre amp, this is here cause of this and that is there cause it needs to be there" xD
damn you OP amp and your black magic xD

Yeah, I know what you mean here. The op-amp black magic bugged me for a long time, and still does some times. I have a hard time with doing things in a way that doesn't derive obviously from first principles. But, here's a couple of things that help me. Op-amps are designed, at least to first order, to match the ideal op-amp equations as well as possible. So, for design purposes, you really can treat the beginning of the design or understanding of the circuit based on the ideal op-amp equations. The specific implementation stuff, like how big your input resistors can be or why there is a resistor to ground from the non-inverting pin, is second order and depends on how the op-amp is actually constructed. That stuff is usually in the docs for the specific device or the application notes for working with that type of device. Stuff like JFET inputs versus BJT inputs or something similar.

The second thing that helped me, and the thing that really turned on the light bulb, was the realization that the two transistor long-tailed pair, differential amplifier, is pretty much the whole thing with op-amps. Read up on the long-tailed pair and you get a better understanding of what's going on in an op-amp. To a large degree, the rest of the op-amp is just there to clean up the output from the long-tailed pair to make the op-amp match the ideal op-amp equations better.

Looking at the long-tailed pair can also brighten the picture when trying to understand the OTA, which seems like even deeper and darker magic than the standard op-amp. It's a good place to start I think.

Here's a list of useful application notes from TI. I usually try to link from the source, TI in this case, but TI seems to have many of their application notes totally screwed up. You should probably download these and save them, since some of them seem to be disappearing from the TI site. In general, TI and National have tons of application notes that are very helpful.

The original doc on op amps, pretty good source and fun to read.
http://www.ti.com/lit/an/sboa092a/sboa092a.pdf
This one is pretty much a standard on the whys of Op-Amps. It's been expanded and turned into a book I think. The book's probably a good source, but I haven't read it.
http://seniordesignlab.com/sd_docs/Links/Op_Amps_For_Everyone.pdf
Since most guitar circuits tend to be single power rail designs, this is a really good doc to read. It explains the why and the how of single-supply design.
http://www.eng.yale.edu/ee-labs/morse/compo/sloa058.pdf

If you want to go full on engineering style and get into the development of the equations , this one goes through the derivation from the ideal op-amp assumptions,
http://www.ti.com/lit/an/slaa068a/slaa068a.pdf

There are more, some of them like the series on audio applications from TI's Analog Applications Journal are really good for specific topics. These will usually pop up when you do a search on a topic, and if they do, I usually go to them first when I'm trying to figure something out.

Thank you very much this is exactly what I was looking for this is what I mean, single rail and split rail designs, I mean sometimes you don't even know what to google for. Just with a couple of posts you made things a hell of a lot clearer to me and now I have the means to learn more.
I always say to myself if i managed to study and learn so many things about electronics these specific things won't be a problem, you just need to find that single thing that turns your light bulb on and say "ahaaaaa that's it now i get it", and with that step everything else is just a matter of time till you understand it.
Thank you again I will start my research and study straight away and if you don't mind i will post again here if I don't understand something
Thank you very much for your time and help this has been of amazing help to me!

[]..
1. Since op amps (lets say a tl082) have a inverting and non inverting input, why would you ever want to invert your signal?
What do you achieve with inverting the input signal? I saw on some designs the input signal gets inverted and on some not :/

Sometimes, you do want to invert the signal, for something like phase correction, or maybe to go into a rectifier or a differential amplifier stage, but there are other reasons.

As you note below, the non-inverting amplifier tends to have a very high input impedance. That's not always a good thing. Circuits do better with matched impedances at interfaces. So, in some situations, the ability of the inverting amplifier to have a low input impedance is an advantage.

In mixer circuits, the inverting input sits near or at ground (or virtual ground), so it's a better place to mix the inputs than other topologies. The same thing can be true of different filter circuits. There are other reasons too.

2. When using an op amp as an input buffer with Av=1 so no amplification, i know that the impedance of the op amp is very high and that that somehow effects the signal coming from the pickups but how? Is it maybe low input impedance of the circuit = easier to drive the signal? I really don't understand whats going on there :/

It mainly has to do with impedance matching. A high impedance output trying to drive a low impedance input has poor power transfer. Cable's resistance and capacitance come into it too. It's harder for a high impedance output to drive the cable than it is for a low impedance source.
 

Sorry for my way of asking questions english isn't my first language xD
Thanks for your help in advance

Your English is perfectly fine and understandable. And, your questions are good too. Certainly, there's a lot more to things than I wrote above, but I hope it helps a bit.

Thank you very much
This is perfect, I get it i remember matching impedance's means full power transmission ideally no loss, that's like with antennas and receivers/transmitters.
Hmmm the thing is in some schematics (very simple 1 op amp pre amps) lets say the input signal is entering the inverting input, now sometimes the non inverting input is grounded and sometimes there is a power source connected to it. I get that with a voltage divider they are trying to create a voltage drop on the non inverting input, but for what reason, i mean these are two completely different things, being grounded or having a couple of volts there. Is it maybe to achieve a certain voltage difference between the inverting and non inverting input? But then having the other input grounded would also create a big voltage difference :/
I know my questions sound pretty vague and there are a lot of factors why are things the way they are and they are not easily answered :/ i need a proper book like " this a op amp pre amp, this is here cause of this and that is there cause it needs to be there" xD
damn you OP amp and your black magic xD

This should be it.
http://www.madbeanpedals.com/forum/index.php?topic=1232.0

thats it thank you very much

Hey guys!
I can't seem to find that collection brian put up with all the pdf books if someone could link that please that would be great
I'm just reading the wampler books someone posted here which are amazing especially the first one with all the explanations of how the different circuits work.
I have a engineering degree its just different when it comes to instruments, the circuits I mean different goals are here.
I'm very interested in reading a bit about op amp circuits since my uni pretty much sucked at explaining op amps. It's very funny how they skip the explanations but when they have to give me a problem with tones of numbers then its okay.
I just can't seem to find good explanations about some things and if you guys could help that would be great
Here goes:
1. Since op amps (lets say a tl082) have a inverting and non inverting input, why would you ever want to invert your signal?
What do you achieve with inverting the input signal? I saw on some designs the input signal gets inverted and on some not :/

2. When using an op amp as an input buffer with Av=1 so no amplification, i know that the impedance of the op amp is very high and that that somehow effects the signal coming from the pickups but how? Is it maybe low input impedance of the circuit = easier to drive the signal? I really don't understand whats going on there :/

Sorry for my way of asking questions english isn't my first language xD
Thanks for your help in advance

ive been using only overdeives and the delux delay from madbean but never at the same time and it stopped working while i was using just the box of rock so there is no reason unless a internal component died. i know they burn and break often but why? is it the transformer?

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i know but this is the thing i had one 9v 300mA for 3  years to power 5 pedals no problem and that one died. i bought the same one and after 3 months it died. i think something inside has given up but measuring while plugged in the mains i first need to know what i should be measuring to check.

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Hello sorry if im in the wrong section!
Okay so this is the deal i have gone through so many wall adapters for powering up my pedals and i stopped counting. The thing is it just stops working :/ The latest one that broke down is a digitech 9V 300mA power supply. It just stopped working after like 3 months and i always unplugg it when im done playing. To open it i have to saw through the plastic. I did that with the others and found nothing visually wrong so I was wondering there has to be someone here who fixed a couple of these power supplies? Can you guys give me some advice on what to keep my eye out what to measure what to check?
I doubt that the transformer burnt out but even thats possible i dont know it doesnt look burnt.
Please help
Thank you!

abroad at the moment but at the back i have 2n3773 transistors and inside its multiple pcbs singlesided. there are alot of big light blue caps. the thing is phase linear are made in the 70s so this could be either original or handmade. i doubt they would put a switch like that on the front and by far as i can tell the input selection switch i didnt see on the original amps so if its handmade clone someone went through alot of trouble making all these extra options

i need some help people. i just got this hi fi amp and on it it says phase linear integrated amplifier 2400-A. now when i googled it nothing comes up. this amp is old and still working great. now i need some help identifying it. it could be hand built but i dont know seems like someone went through the trouble of making it almost identical the lettering and everything. im just trying to find out more about it. i would aprichiate any help and i can take some pictures of the insides if needed. it has alot of carbon composite resistors and alot of other vintage components.
thank you for your help

ps a picture of the amp front and back.

i dont remember which one is the L one but ive built 2 urchins and ive used the bigger one with no problems and no twisting of leads

search the forum there has to be proper voltages posted so compare them. if you have a suspicion check the components leading to the pin and check their solders.