Small Stone Build Problem

Started by stalefish, December 13, 2007, 09:34:33 AM

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stalefish

Hi all. I think this may be my first post here but I've been lurking for quite some time now, and have come away with a number of successful projects, thanks to the great info found here. Successful until now, that is. :-\

I'm building a Small Stone using a Tonepads pcb (ordered from their site). I've added a number of mods:

1) Mark Hammer's Phase Filter mod (http://www.diystompboxes.com/smfforum/index.php?topic=16305.0)
2) Depth control mod using a 100k pot in series with a 22k resistor in place of R13 (http://www.diystompboxes.com/smfforum/index.php?topic=19331.0)
3) Dry lift mod using a SPDT switch to ground one side of R8
4) Univibe mod by changing the values of C4, C5, C9 and C8
5) Replaced R11 and R42 with 10k trim pots to control the output volume and feedback

I'm using 4 DP3T on-on-on switches to switch between the Phase Filter, Univibe and stock values for caps C4, C5, C9 and C8.

Aside from these mods, the rest of the component values, transistors and ICs are as what is listed in the Tonepads build instructions.

Now....here's the problem. I get the correct phasing sound when the 'Colour' switch is on. However, when it's off, I get a clean sound without phasing. After some probing with a good ol' debugging probe, I realised that the wet signal seems to be stopped by my Depth control after the Q10 and R11 junction. Funny thing is that before it gets stopped (tapping from the Q10/R11 junction), the wet signal sounds a little bit odd. Instead of a phasing sound, it sounds as if the notes played are being detuned. Again, it sounds as it should when the Colour switch is on. Through it all, the Rate control is working correctly.

Thanks in advance for the help and apologies for the long long post!!