Valve Wizard U-Boat - no octaver but fuzz noise

[eve-the-frog]

Hi everyone,
I'm a newbie in making guitar FX, but I have to say that I already built one that works great (Madbean Cave Dweller). I guess it means that i'm not totally lost in the DIY FX world...
An by the way I'm french, so please exuse my bad and approximate english. I dot my best to be understood...

I just built this Valve Wizard U-Boat octaver from the verified layout here :


On my first attempt I had an issue with my soldering iron, and as the result was just a kind of fuzz effect in the sound of my guitar with no octaver at all, I thought I burn a few caps.
So I bought again all the caps and make a brand new vero to get a clean job. But the result is exactly the same

I don't think I could have done the same mistake twice (however it's possible). I double checked my vero cuts, strips and components misplaces, and also try another set of LM833 and TL072 I have in stock : still the same.
The effect only produce a light (and ugly) fuzz effect with other noises and buzz. The sound of the guitar is perctly clean with mix pot all the way down.
I also tried to place J112 in both direction : the fuzz effect is slightly stronger with reverse direction (compared to layout).

Here are pictures of my built :




I don't know the function of the trim pot : in my case it's just acting like a gain pot for the fuzzy sound.
An I'm still not sure how to wire the DPDT switch (which I don't know what it should do) so here is a picture  :


And what I acually did wich is not obvious in the above picture :


Thanks for reading... and helping !

[PMowdes]

Hi

A quick look says you have wired the switch wrong.

with the lugs on the switch horizontal the numbering should be

1 - 4
2 - 5
3 - 6

Try rewiring the switch and if that doesn't work we can have a better look.

Also some voltage readings at the legs of the IC's would be really useful.  

Ic's are numbered differently

1 - 14
2 - 13
3 - 12
4 - 11
5 - 10
6 - 9
7 - 8

or

1 - 8
2 - 7
3 - 6
4 - 5

Bon chance :)

[eve-the-frog]

Oh yeah !
It works now.
I found a DPDT wiring diagram on the web that was wrong...

Many many thanks PMowdes !


I now have another question : the sound seems pretty "lo-fi" with distorted noise, especially when I turn the track pot. When I turn this pot slowly there is a "crackling" noise near the middle position. And the finger-on-string-slide-noise (is there a proper term for that ?) as well as any slight undesired sound coming from my fingers and picks on the strings make this crackling noise.
Is it a normal behaviour for this effect ?

[PMowdes]

I cant help you with those questions, I'm not familiar with the circuit.  It might be a good idea to add a question on the comment section of the U-Boat thread.

Measure your pin voltages as well, it is a good way to check that everything is working correctly.  Also an audio probe is a very good tool to make sure the audio path is behaving correctly.

[eve-the-frog]

Thanks for the advice. I will add a comment.

But the end of your reply sounds like chinese to me

Anyway, the effect is really cool like that and it works thanks to you !

I now have to put it in a box... Busy afternoon in the garage