# Semi-sweet 3



## HamishR (Mar 21, 2020)

Well this is an interesting one... As usual the build went without incident because the boards are so good. (Do I end up with free stuff for always saying that??)

Is it just me or does this pedal have low output?  I find this with pretty much any Cornish designed pedal I have built - I have to almost max the volume to get unity. I can get probably just above unity with volume on full but most other pedals I build have way more level than this. It reminds me of the Honey Bee in that regard - only just enough grunt!

The tones are interesting. Again, it might just be my build and maybe I have done something wrong but there isn't really that much gain for a "distortion". More like an overdrive really, especially with a Strat.  Things is it sounds really pretty good with a Strat - if you're into your Gilmour sustainy stuff through delay and reverb it sounds suitable vocal and has decent definition on bass strings etc. The treble sounds a bit detached from the tone without any other effects but makes more sense with ambience added. But the Strat sounds big and full in lots of good ways with this pedal.  If it had a bit more dirt and level available it could be killer!

With a Les Paul it sounds quite artificial to me, unless you were to pour on loads of reverb etc.  But - as a booster into my other low-gain ODs it sounds huge. So stacked I like it and with a Strat it has huge potential - but I just feel it isn't quite there yet. Have I wired it up correctly? I wanted it to be TBP.


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## music6000 (Mar 21, 2020)

Have you tried running it as it was designed with the Buffered Bypass to see if you are losing what the Pedal is giving you as it is?
I may be wrong but sometimes the whole structure of the Pedal changes when Buffers are modded! 
You may want to Check your Resistor values!!!


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## HamishR (Mar 21, 2020)

There are one or two resistors where I subbed close values because I didn't have the correct ones, but they were within 10%. 560R for 510R and 100R for 91R I believe.  Could it make much difference?

You have a very keen eye!  Thanks for your trouble!


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## Chuck D. Bones (Mar 21, 2020)

Unless you have extremely hot pickups, you should have no problem dialing the output well above unity.  Those resistor subs are fine.  I would have used 470R for R13 since it sets the max gain, but the difference is only ±1dB. Looks like you might have installed 10K for R12, should be 100K.  Hard to tell if the 4th band is red or orange because of the lighting.

If it's built right, the buffered and unbuffered bypass volumes will be the same.

R8, R9 & R17 don't do anything.  I think they are leftovers and Cornish forgot to remove them.


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## music6000 (Mar 21, 2020)

If you magnify it, R12 is 100k.
If you were to remove R24 - 91r that has been subbed with 100r & replace with a jumper, How much would Increase in Headroom be?


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## Chuck D. Bones (Mar 21, 2020)

0.1dB.  Not enough to notice.  Something else is wrong.  Inspect all of the solder joints.  R23 is another "do nothing" part.


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## Barry (Mar 21, 2020)

Looks good, hope you sort out the sound!


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## HamishR (Mar 21, 2020)

Thanks for the help guys! I'll have another look at the soldering.


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## taylorbusby (Aug 24, 2020)

I just built this today and Im having the same problem


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## music6000 (Aug 25, 2020)

taylorbusby said:


> I just built this today and Im having the same problem


Where did you get your 1N34A's ?
Did you test the Voltage Drop


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## taylorbusby (Sep 2, 2020)

Got the from Tayda. I’m not sure how to test voltage drop. I’m kind of a newb


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## Chuck D. Bones (Sep 2, 2020)

The Vf that I measured on the Tayda 1N34's I have are in the same ballpark as other Ge diodes.  This circuit will hit the diodes with about 2.5mA max.  Vf is around 350mA at that current.  With all the controls dimed, you should be getting somewhere close to 2Vp-p at the output.  This is well above the output of passive pickups.

Methinks there is an error in the circuit build.  If you have an audio probe, listen to pin 3 of the HICUT pot, then listen to IC2 pin 3.  They should sound the same.  Then listen to IC2 pin 6, it should be noticeably louder there.

You're testing this with guitar -> SS3 -> amp, right?  No other toys?

Hey Hamish!  Did you ever get yours working?


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## taylorbusby (Sep 2, 2020)

Chuck D. Bones said:


> The Vf that I measured on the Tayda 1N34's I have are in the same ballpark as other Ge diodes.  This circuit will hit the diodes with about 2.5mA max.  Vf is around 350mA at that current.  With all the controls dimed, you should be getting somewhere close to 2Vp-p at the output.  This is well above the output of passive pickups.
> 
> Methinks there is an error in the circuit build.  If you have an audio probe, listen to pin 3 of the HICUT pot, then listen to IC2 pin 3.  They should sound the same.  Then listen to IC2 pin 6, it should be noticeably louder there.
> 
> ...


yes just guitar ss3 to amp. Im also getting a high squeel when I turn the treble pot up. I dunno I just stashed it away and started on another project.


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## HamishR (Sep 2, 2020)

No I never did get mine working - I don't like changing things on PCB and lost interest!


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