Echo nightmare Kit distortion

[Gothsome]

Hello!
Im new to this board.
Im a beginner with my third diy build and the facebook groub sadly couldnt help me with my problem..

I have a Echo Nightmare Kit and i have a distortion in the sound.
When you turn the Fuzz dwon it gets quieter, but you can still notice it.
Here is a video:https://www.youtube.com/watch?v=2yQdPTkilk8

Thank you in advance!



https://pcbguitarmania.com/wp-content/uploads/2019/07/Echo-Nightmare-building-doc-v1.2.pdf

[stallik]

Firstly, welcome!

Only listening to your clip on a mobile device but I'm presuming you're referring to what I'd call an overall crackle which appears to be pretty constant.

Things I'd check first are, if your using a power supply, check it with a battery. Next, shield it. Either temporary with a tin can or put it in a box

[rankot]

If there's distortion on echoed signal only, not on the original (first), then try to remove those diodes in feedback loop of the op amp, or replace them with blue LEDs.

[Gothsome]

Thank you!
A coleague of me told me that i propably need a rectifyer if it is called right in english.
Is ist possible to add this feature?

I use the Power Supply for my other pedals too an they dont have this distortion.
It is an older model with a trafo.

[antonis]

try to remove those diodes in feedback loop of the op amp, or replace them with blue LEDs.

Diodes only exist in TC1044 charge pump.. 

[anotherjim]

Seems an odd choice to run the 78l05 regulator for the PT2399 off the charge pump output. PCB's can be hard to mod, but you could lift the input pin of the 78l05 out of its hole and wire it to the +9v node (cathode of D2). I think that should be a happier loading for the charge pump chip.
The 9mA supply current for this may well be a measured average, but I think the peak current can be somewhat higher which is why I offer the above suggestion.

Also, crackle can be a bad capacitor. Try tapping parts with a chopstick to root that out.

The distortion effect appears to be simply from overdriving the PT2399 into clipping.

[Gothsome]

Seems an odd choice to run the 78l05 regulator for the PT2399 off the charge pump output. PCB's can be hard to mod, but you could lift the input pin of the 78l05 out of its hole and wire it to the +9v node (cathode of D2). I think that should be a happier loading for the charge pump chip.
The 9mA supply current for this may well be a measured average, but I think the peak current can be somewhat higher which is why I offer the above suggestion.

Also, crackle can be a bad capacitor. Try tapping parts with a chopstick to root that out.

The distortion effect appears to be simply from overdriving the PT2399 into clipping.

I think youre right - i used a 9v a vew minutes ago and the noise is still there and it sounds to my amateur ear as if an effect gets repeated.
If i rise the feedback (echo?) te noise gets repeated as only the sound of the guitar should be.
With feedback at zero it souunds a bit like my bike.   

Here is the Video with a longer test and with 9v Battery:
https://www.youtube.com/watch?v=EBpFpOg_iPg

I tapped every cap and there is no sound than the distortion-vtwin.

i will test the 78l05 method - sadly the kit didnt came with an socket so i have to desolder it first.

A big thanks - im so exited!

[Gothsome]

putting the input pin to 9v was not the solution.
Sadly i broke the 78l05, but i had a last spare from another box.

Pin 1 = 4,99V from the pt2399

Anti Latch up:
Pin 6 to ground = 106 KOhm

Pin 3-4 connected to each other and ground

i looked this here up:
https://www.electrosmash.com/pt2399-analysis

i dont have an oscilloscope but a multimeter and i dont know what i schould measure to see what could be faulty.

[rankot]

try to remove those diodes in feedback loop of the op amp, or replace them with blue LEDs.

Diodes only exist in TC1044 charge pump.. 

Sorry, my mistake, thought this is a clone of Ibanez EM5.  Should have look at the images more carefully!

[Gothsome]

Today i have measured every chip:

voltages with power. but no devices:

f0919
1: 0
2: 2,6V slowly rising and sinking
3: 3,6V slowly rising and sinking
4: 9,5V
5: 6V
6: 6V slowly rising and sinking
7: 3,6V
8: 4,5V
--
9: 0,83V
10: 0,83V
11: 4V
12: 4V
13: 0
14: 0,1V
15: 3V
11: 0,3V


pt2399
1: 4,9V
2: 2,48V
3: 0
4: 0
5: 2,9V
6: 2,49V
7: 0,7V
8: 0,7V
--
9: 2,49V
10: 2,49V
11: 2,49V
12: 2,49V
13: 2,49V
14: 2,49V
15: 2,49V
11: 2,49V


tc1044s
1: 10,6V
2: 5,17V
3: 0
4: 0,111V
--
5: 10,7 V
6: 7,1V
7: 5,8V
8: 0,27V


ne5532p
1: 6V slowly rising and sinking
2: 6V slowly rising and sinking
3: 6,9V
4: 0
--
5: 7,89V
6: 7V
7: 3,9V
8: 3,8V

[Gothsome]

try to remove those diodes in feedback loop of the op amp, or replace them with blue LEDs.

Diodes only exist in TC1044 charge pump.. 

Sorry, my mistake, thought this is a clone of Ibanez EM5.  Should have look at the images more carefully!

I think its a clone of the Death By Audio Echo Dream 2.
The knobs are all the same and even at the same position.

[garcho]

At a quick glance, that NE5532 is off, pin 8 is V+, it should be 9V (or whatever your power supply's V+ is)

[Gothsome]

At a quick glance, that NE5532 is off, pin 8 is V+, it should be 9V (or whatever your power supply's V+ is)

What if i bridge the pin directly to the 9V input?
I would bend the leg out and use to test ist a breadboard cable.

[duck_arse]

[Gothsome]

At a quick glance, that NE5532 is off, pin 8 is V+, it should be 9V (or whatever your power supply's V+ is)

I have now removed now the chips one by one and even with just the pt2399 plugged in there is this noise.
I thought maybe the 2206CP would be broken too...
I will try to resolder anything from the ingoing signal path.

[eh la bas ma]

I did this build recently for a friend.

I remember the circuit gets very noisy when the Delay Time pot reaches the end of the first half of its rotation (around 10 or 11 o'clock). Even more noisy when Depth is set on high values ( past 12 o'clock, if I recall correctly).
I was surprised too, so I went on utube to watch some demo of this circuit.
The other builders had the same amount of noises.

It's a "Lo-Fi" delay so it is supposed to be this way. At some extreme settings it sounds like there is a whole factory inside the box...

If you still have noises with the Delay pot and the Depth pot fully CCW, then you might have something wrong somewhere.

[Gothsome]

I have looked up the original:
https://cdn.shopify.com/s/files/1/2261/8655/products/EchoDream2Face_2048x.jpg?v=1569096129

And made the discovery, that i can stop this noise in turning the  here called d time to the lowest.

I marked the resistor and started slowly turning it higher and at 32,7 KOhm it slowly appears again

[eh la bas ma]

I learned a wise and simple trick to reduce background noises from any circuits, on this forum. I think it was Electric Druid's idea (may the Current flow steadily in his Circuits),  it helps me with a Flangelicious :

Increase as much as possible the input volume before the effect, and decrease the volume after the effect (with any kind of quiet volume pedals). It should give you a better signal/noise ratio, thus a cleaner modulation.

[Gothsome]

I did this build recently for a friend.

I remember the circuit gets very noisy when the Delay Time pot reaches the end of the first half of its rotation (around 10 or 11 o'clock). Even more noisy when Depth is set on high values ( past 12 o'clock, if I recall correctly).
I was surprised too, so I went on utube to watch some demo of this circuit.
The other builders had the same amount of noises.

It's a "Lo-Fi" delay so it is supposed to be this way. At some extreme settings it sounds like there is a whole factory inside the box...

If you still have noises with the Delay pot and the Depth pot fully CCW, then you might have something wrong somewhere.

heres a video how it should be:
https://www.youtube.com/watch?v=hcglMoQfSfs&t=33s
and here is mine 
https://www.youtube.com/watch?v=eU0XhSk8g-I
There is a permanent distortion.
I have used the out pin to connect diffrent parts of the Board and i found out there is no distortion on the leg 2 and distortion on leg 7 of the IC1.
If i have to guess it could be in the va section.

[ElectricDruid]

I notice there's a big knob labelled "Fuzz" in the first video which the player keeps turned right down.

What's the "fuzz" setting in your video? I can't tell since the pots shafts don't have knobs and mostly don't have lines drawn on. Looking for a mysterious distortion wouldn't be that mysterious in a circuit with a "fuzz" knob turned up, would it?!?

To be honest, I don't hear anything massively unexpected for a echo circuit that isn't boxed up and can be pushed to oscillating feedback. That makes weird crunchy noises, like yours does. That's normal, pretty much. Could it be quieter? Yes, a bit. Might it be quieter in a shielded box? Yes, perhaps. Could the problem be a bad joint somewhere or something else equally simple? Yes, possibly.

There's certainly nothing that screams "huge mistake" here. I think your circuit is basically ok. There might be some small thing still to find, but there's nothing fundamentally wrong with it (like a fried chip or anything).