I built a Tube Screamer and it has a very low volume output

[kraigen]

Hello, all!
This was my first build, a TS808, and I used the following layout: http://effectslayouts.blogspot.mx/2015/02/ibanez-ts808-tube-screamer.html.
The effect itself sounds like it should, however, the volume is considerably lower than the bypassed volume at 12 o'clock, and to reach the same level I have to put the pot at almost max. For what it's worth, I have measured the resistance across the pot and it is correct. I don't know where to go from here.

[Elijah-Baley]

Check all the resistors, the orientation and value of the caps, and the wires.

[duck_arse]

on pcb, or perfboard? can we see photos of your build, we might spot something?

also, welcome to the forum, of course.

[kraigen]

Check all the resistors, the orientation and value of the caps, and the wires.

First of all, thank you, the caps and the resistors all have the correct value and the polarity is right also, there is continuity on all of the wires.

[kraigen]

on pcb, or perfboard? can we see photos of your build, we might spot something?

also, welcome to the forum, of course.

Thank you for taking the time, here are some pictures (I'm not proud of my cable management, but I guess it's one of those things you learn with time) The underside of the PCB has double sided tape, so there are no shorts there, and the lid of the case is lined with electrical tape as well, no cold solder joints and there is continuity where there should be

[kraigen]

[kraigen]

So, I put together an improvised audio probe and went through the circuit and there seems to be no problems along the audio path (the blue path in the layout), I also measured the voltages across the IC pins and they are the following:
1- 4.51v
2- 4.59
3- 4.51
4- 0
5- 4.51
6- 4.5
7- 4.51
8- 9.1

[GibsonGM]

So, I put together an improvised audio probe and went through the circuit and there seems to be no problems along the audio path (the blue path in the layout), I also measured the voltages across the IC pins and they are the following:
1- 4.51v
2- 4.59
3- 4.51
4- 0
5- 4.51
6- 4.5
7- 4.51
8- 9.1

Welcome Kraigen....no probs along the audio path - but there must be, because the output is low, right?

Voltages look good.

Are you SURE your gain pot is 500k?  The volume isn't much greater at pin 1 of the chip?  How about on pin 6?  If no increase, then I would really suspect a resistor value is wrong in the feedback path of one or the other gain stages.

[kraigen]

It goes up to about 430k (the drive pot), the volume is very high on pin 1 and somewhat higher in pin 6

[GibsonGM]

Seems like if you have a high volume on Pin 6, you should be able to trace the audio to where it drops and becomes significantly lower, right?   Assuming the volume on pins 1 and 6 are louder than what you get at the output, that they are nice and loud?

Audio probe one side of the volume pot....one side should be quite loud, the other no sound at all, the middle will vary.   If you get this result, then the problem is around the last transistor, the output buffer.  You'd want to provide voltages at the transistor, in that case.  Q2 on the board.

This is why schematics are so important.  I'm looking at how the circuit works on a schematic, which is about impossible to do with a board diagram...

[duck_arse]

the more we can see of your wires, the easier it is to spot - you have no ground wire on the left-most jack in yr photo. add one, report back.

[and are you really wearing those pants?]

[kraigen]

Seems like if you have a high volume on Pin 6, you should be able to trace the audio to where it drops and becomes significantly lower, right?   Assuming the volume on pins 1 and 6 are louder than what you get at the output, that they are nice and loud?

Audio probe one side of the volume pot....one side should be quite loud, the other no sound at all, the middle will vary.   If you get this result, then the problem is around the last transistor, the output buffer.  You'd want to provide voltages at the transistor, in that case.  Q2 on the board.

This is why schematics are so important.  I'm looking at how the circuit works on a schematic, which is about impossible to do with a board diagram...

Pin 1 is much, much louder than pin 6 and pin 6 is a little louder than the bypassed output, is this right?
Also, what voltages should I get from Q2, the collector and emitter voltages with ground as a reference?

[kraigen]

the more we can see of your wires, the easier it is to spot - you have no ground wire on the left-most jack in yr photo. add one, report back.

[and are you really wearing those pants?]

I added it with no results.
And yes, it was midnight in Mexico, those are my pajama pants

[Kipper4]

check this out

http://www.diystompboxes.com/smfforum/index.php?topic=117224.0

[kraigen]

Thanks for taking time to help me!
I double checked the in and out cables and everything is in order.

[Kipper4]

There's some voltages in that thread too.

[kraigen]

There's some voltages in that thread too.

The transistor voltages are measured with one terminal to the pin and the other to ground?

[Kipper4]

Red to pin
Black to gnd.
Be careful not to short em.

[kraigen]

Thanks, I'll be going out now, but I'll measure and post them in the evening, after I get back home.

[Kipper4]

It would be worth you're getting the data sheet for the transistors you used to double check the pinout against what you have in the build.

A schematic would help too.