No octave down in Giant Hogweed

[Jules]

I have built DRolos Giant Hogweed and I love the sound of the distortion and octave up section...but the octave down shoes not appear to be working.
I have double checked parts value, re flowed and tried a few different tl072.
I accidentally took a big piece of the board out with my step drill (don't ask!)
It is at the top left and I have added a jumper that has fixed 1 part of the broken track.
If David himself happens to see this post 'could the damaged board be contributing to my lack of octave down? Every other pot functions as it should.

[playpunk]

Do you have all of your transistors in and oriented correctly?

I forgot a transistor in my build and had the same problem


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[Jules]

All the transistors are in their correct positions and oriented correctly it is something else. Is it a prominent octave down sound this should be making or more subtle?

[playpunk]

I find it pretty prominent. It gets all wooly and synthy


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[drolo]

If the damage to the board is only what is shown on the picture, I don't think it is the reason to the issue. Seems like just the main power trace was hit.

When you engage the octave part, turn the octave up volume completely down and check if turning the octave down volume pot has any effect.

You may need to use an audio probe to see if the signal gets everywhere it's supposed to go and is not interrupted somewhere.

[stringsthings]

I had the same problem when I was building mine.  It turns out that there was a short on the solder side of the board.  Two connections were very close together and a bit of component lead was causing the short.  If you check around T4 and D3, that's a good place to start looking.  I found the problem with the help of an audio probe.  There should be a good signal going into the Octave Down section at point "A".  And the output of that section would be around R14 and C16.

[Jules]

Thanks for the response folks, I will investigate a bit further.