Tri-Vibe Vero (slacker layout) Distortion & Low Output

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This Tri-Vibe project is finally working.  I've found and corrected a couple of mistakes, and in that process re-flowed all the joints, measured all the resistors and all that jazz.  Right now it works with low input signals.  With a hard chord strum there is a distortion that sounds like a mis-biased transistor, sharp and blatty.  The overall output is noticeably lower than bypass.  In addition, there is a faint, high-pitched whine in sync with the tremolo circuit.  I added a 2k7 resistor off of pin 8 of the TL064 and an LED (which corresponds to pin 7 of u3b of the ROG schematic at http://runoffgroove.com/tri-vibe.html).

Also, to help transfer from TL062 in the ROG schematic to the TL064 in the Slacker vero:
pins 1-3 are U2b
pins 5-7 are U2a
pins 8-10 are U3b
pins 12-14 are U3a

If you have any suggestions as what might be causing the trouble, I'm all ears.






Thanks,
CHAD

[seedlings]

Every time I read through the 16 page Tri-Vibe thread, I'm reading for a different purpose. This time it sunk into my thick skull that the NE5532 worked better for some builds. Well, it works better for my build too.  Replacing the Tl072 with the NE5532 fixed all the problems, including the on/off click that I'd planned to fix with another 1M before the input cap.

The only thing I notice now is the circuit is brighter/thinner than bypass, which should be helped with a larger input cap.

CHAD

[seedlings]

Adding 10k to the existing 47k feedback resistor between NE5532 pins 6&7 gives just enough more boost so that effect ON has the same perceived volume as bypass (to my ears).

-Is there any way to reduce the white noise floor?  This noise varies with the tempo, so it's probably coming from the LM13600.

I've tried increasing opamp feedback loop capacitance before and after effect, and that's not doing the trick properly.  Can the noise floor come from the TL064, and would a different quad opamp be better suited?

CHAD

[seedlings]

There must be something magical about forums.  Whenever I have a problem, I spend hours trying this and that, but the solution never comes until I write a post...

Regarding noise, I found that increasing the first gain stage and decreasing the last gain stage helped  significantly.  The first opamp stage has the 15k and 4n7 to set gain with the 47k feedback resistor.  I put a socket in place of the 15k, and replaced the 4n7 with a 1uF.  Starting at 3k3, there was distortion, and I progressed up to 10k when the noticable distortion was gone with humbuckers.

The last gain stage is inverting, so a socket went in place of the 47k feedback resistor. I brought this down until the bypass and effect sounded about the same loudness. Curiously this was also 10k.

Now there is very faint noise, but she's quite usable in front of the fuzz and vulcan drive.

I'm calling this one DONE!

CHAD