Kliché Mini - Low Gain, Very Loud

[jamie j.]

Hi kids. I have an issue with my Kliché Mini. The gain adjustment does not add a lot of overdrive sound but the pedal is stupid loud. Also, this is the 2nd I've built and the first one works as expected. Everything seems to be in place. I don't see any bleeds or unwanted connections in the solder. Any ideas? Below are pics.

 

[swyse]

The readings sound about right.
I'm still not 100% convinced,I think that you may have an incorrect resistor.
Can you pull R9 out to be sure it's 2K - Red, Black, Black, Brown, Brown ????
As I said, Being Colorblind sure has it's challenges!

View attachment 29599

I thought the same, I think it's just a poorly marked resistor or a bad color choice by the manufacturer. if it was brown band on the far right and it was a 1k resistor he would have even more gain on the distortion portion because of how R9 is being used right?

 

[jamie j.]

The readings sound about right.
I'm still not 100% convinced,I think that you may have an incorrect resistor.
Can you pull R9 out to be sure it's 2K - Red, Black, Black, Brown, Brown ????
As I said, Being Colorblind sure has it's challenges!

View attachment 29599

I can 100% assure you I do not have a resistor out of place. I label them first and still read them when I put them on the board. Also, if a resister ended up in the wrong spot another resistor would be missing a spot and I would catch it.

I double checked the caps as well and they are correct. The components are in the correct spot.

 

[music6000]

I understand where you are coming from but in the 2 pictures you have supplied, R9 - 2K Colour code does not match the resistor Colours in the Picture
I have spent a lot of my time trying to help you with a issue that is indicating a wrong component.
I can't help you if you are convinced you have it correct!!!

 

[swyse]

I'd check for continuity between these, hopefully the numbers help. This is the whole string between the distortion section and the summing op amp (in random order)

 

[jamie j.]

I understand where you are coming from but in the 2 pictures you have supplied, R9 - 2K Colour code does not match the resistor Colours in the Picture
I have spent a lot of my time trying to help you with a issue that is indicating a wrong component.
I can't help you if you are convinced you have it correct!!!

I understand and completely appreciate your help.

I took the measurement and it was 2k. The resistor above it reads 47k and the one below reads 390k (this kit provided a 390 instead of a 392 but that was specified in the BOM). So, that just doesn't seem to be the issue. Now, my photography may be an issue...

 

[jamie j.]

View attachment 29605
I'd check for continuity between these, hopefully the numbers help. This is the whole string between the distortion section and the summing op amp (in random order)

All of the numbers have continuity with each other.

 

[jamie j.]

I understand where you are coming from but in the 2 pictures you have supplied, R9 - 2K Colour code does not match the resistor Colours in the Picture
I have spent a lot of my time trying to help you with a issue that is indicating a wrong component.
I can't help you if you are convinced you have it correct!!!

Took an up close pic. Is this better?

 

[swyse]

new idea, maybe the distortion side is fine and its the summing op amp boosting one of the clean paths to the stratosphere. can you compare the resistance readings in circuit of these 4 resistors here to the resistance readings of your working unit in circuit? If one of these has a lower resistance than your working unit somehow it would be getting more gain from the summing op amp.

 

[jamie j.]

new idea, maybe the distortion side is fine and its the summing op amp boosting one of the clean paths to the stratosphere. can you compare the resistance readings in circuit of these 4 resistors here to the resistance readings of your working unit in circuit? If one of these has a lower resistance than your working unit somehow it would be getting more gain from the summing op amp.
View attachment 29612

Working pedal:
14.98k 11.95k 21.98k 26.95k

Bunk pedal:
13.17k 11.96k 22.91k 20.95k

That 27k is reading a little low on the bunk pedal.

 

[swyse]

If I'm doing my math right, the difference in gain would be 14.5x with the 27k and 18.7x with the value in the pedal, and with the 15k resistor you have 26x, but with the 13.17k you get 29.7x, I'm not sure if these two differences would account for your massive clean signal when combined though, but it might be worth looking into.

 

[jamie j.]

If I'm doing my math right, the difference in gain would be 14.5x with the 27k and 18.7x with the value in the pedal, and with the 15k resistor you have 26x, but with the 13.17k you get 29.7x, I'm not sure if these two differences would account for your massive clean signal when combined though, but it might be worth looking into.

I'm not really sure what to do with this info. Math is not my strong suit. and that 27 would have read close to 27 before I mounted it to the board.

 

[giovanni]

Our ears don’t hear linearly, but in log scale. So unless you have a 10X difference in gain, it would be barely audible.

 

[giovanni]

Did you get around doing some audio probing? Since you have a working unit, you can compare various points on both pedals and really narrow down where the issue is coming from. Given that we ruled out most common issues, I don’t see any further constructive debugging without the audio probe.

 

[jamie j.]

Did you get around doing some audio probing? Since you have a working unit, you can compare various points on both pedals and really narrow down where the issue is coming from. Given that we ruled out most common issues, I don’t see any further constructive debugging without the audio probe.

I do not own an audio prob. Would it be helpful since I do have audio?

 

[giovanni]

I do not own an audio prob. Would it be helpful since I do have audio?

Yes, extremely. There are tons of guides on how to build one, you basically just need a jack and a capacitor.

 

[Boba7]

Yes, an audio probe is easy to build and extremely useful.

Did you already post voltages?

Does the treble pot work as expected?

Could you try a pair of back to back diodes (germanium or schottky - bat46, bat41) in parallel with one of the Ge diodes? Just to see if you get distortion with a new set of diodes.