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I've build the probe and checked the circuit & the noise seems to be gone. I've checked everywhere with the schematic and couldn't find anything weird.
A big thank you guys, been very helpful!

I don't have an audio prob & don't have access to one unfortunately :/

Have you read Jacob's instructions in the tech help rules thread for creating an audio probe? It's literally a capacitor and a cable. I just use alligator clips, so I don't even have to destroy a cable.

No I haven't, can you send me a link for it?
Merry Christmas btw guys

It's the tech help rules thread. It's the sticky in the tech help section. It's required reading Actually, this thread should be there, I'll ask to have it moved.

Just found it, I'll build it over the weekend, keep you guys posted.

I don't have an audio prob & don't have access to one unfortunately :/

Have you read Jacob's instructions in the tech help rules thread for creating an audio probe? It's literally a capacitor and a cable. I just use alligator clips, so I don't even have to destroy a cable.

No I haven't, can you send me a link for it?
Merry Christmas btw guys

So I've checked all the 100K resistor (unsolder a lead to test them) and they all are 100K
Also I've notice that Q4 is the one with the higher reading, not Q3 ( my bad). I've said earlier in this post that I have a DC reading in the tone pot, lug 1 and 2 read 4. 10-40V and lug 3 read 1v and just a bit more. I don't know if it's normal or not, might me the reason why the strange hiss/woosh in the tonestack.

You do you guys think?

I still don't know how your emitter can be that high with a 390R, but the numbers are more normal for Q4 at least.

Maybe I missed it, but have you audio probed to see where you're actually losing signal?

There should be DC in the tone pot. There's no capacitor between C3 and Tone 1.

I don't have an audio prob & don't have access to one unfortunately :/
Wich emitter are we talking about at this point since Q4 seem to be more normal? At R23 I have a 2k7 instead of a 2k (couldn't find any at my local shop)

So I've checked all the 100K resistor (unsolder a lead to test them) and they all are 100K
Also I've notice that Q4 is the one with the higher reading, not Q3 ( my bad). I've said earlier in this post that I have a DC reading in the tone pot, lug 1 and 2 read 4. 10-40V and lug 3 read 1v and just a bit more. I don't know if it's normal or not, might me the reason why the strange hiss/woosh in the tonestack.

You do you guys think?

I just did the exact same project with the exact same problem.

Can you post the color code of the resistor you have in R24?

I accidentally had a 100k resistor there instead of a 100R resistor.

-C

edit:corrected nomenclature

It's brown/black/brown/gold & my dmm read 100R

Yes, the collectors are too low

Q1 read 0.12;0.76;5.14
Q2 read 0.11;0.75;5.77
Q3 read 0.75;1.38;6.20
Q4 read 0.11;0.75;5

They used to be even lower though

Q3 is wrong. Look at the schematic -- it has the same parts and biasing as Q2. So how can its biasing be SO significantly different? How can its emitter voltage be so high if there's only a few hundred ohms there?

That's the part I don't get as well... I've checked both bias resistor & they do in fact read 12k each. The emitter read 390R as it should... Any idea what might be causing this? Is the reading on Q1,2 & 4 any good though?

Check all the resistors connected to that transistor. replace them if you have to. When you say "reads" are you using your eyes or a multimeter? Your eyes are very bad at telling you how many ohms something is.

I'm using a dmm. So I've checked the resistors on all four Q & they are all good except R3,9 and 14 wich read 38.8K instead of 100K and R21 81K instead of a 100 as well.
I'll go buy new resistors this week and see if that does the trick! Could the probleme be there???

Yes, the collectors are too low

Q1 read 0.12;0.76;5.14
Q2 read 0.11;0.75;5.77
Q3 read 0.75;1.38;6.20
Q4 read 0.11;0.75;5

They used to be even lower though

Q3 is wrong. Look at the schematic -- it has the same parts and biasing as Q2. So how can its biasing be SO significantly different? How can its emitter voltage be so high if there's only a few hundred ohms there?

That's the part I don't get as well... I've checked both bias resistor & they do in fact read 12k each. The emitter read 390R as it should... Any idea what might be causing this? Is the reading on Q1,2 & 4 any good though?

Yes, the collectors are too low

Q1 read 0.12;0.76;5.14
Q2 read 0.11;0.75;5.77
Q3 read 0.75;1.38;6.20
Q4 read 0.11;0.75;5

They used to be even lower though

Any one???

So I've checked some other reading on the board:
R6, R12, R17, R20, R22, C14 and C15 all read 9V (or so)

I also did check the voltage reading on C2, C3 are reading 1,18V
C5, C6, C8, C9 also read 1,18V but 0,02V on the diode side.

C1, C4 read 0,03V
C11 is reading 0,37V
& C13 read 0,97V

Should it be reading these voltages or are they wrong???

Ok guys so me again... Took the time to sit down and play with the pedal and there is something else that I didn't notice the first time around: depending on where the tone knob is set there's a weird pulsating sound ( treble side) or a kind of woosh (bass side)

Hey guys, just managed to clean the board with some isopropyl alcool & the board started working correctly. Maybe there was a tiny bridge somewhere. Anyway thanks for the help, really appreciated! 

Not so far :/

Yeah you're right... it was a mislabeled bag. So I've change R22 for a 10K & the other for a 12K (it was last thing I had lying around) but the reading on all four Q are all way off, max on all Collectors is about a 1v-1.2v.

Had to do some miracles as well since a I screwed a solder pad :/

http://s1370.photobucket.com/user/spacedave23/media/10754845_10152827332809798_363868283_n_zpsa08a02d4.jpg.html?filters[user]=141819916&filters[recent]=1&sort=1&o=0