Strange behaviour in the Simple Dual AD/AR

Hi! I’ve been searching and didn’t found any info around here.
I’ve made the Dual AD/AR from This post and made the 10k ohm modifications.
The module works perfectly despite the fact that I cannot trigger one of the envelopes, and when I trigger the other one, the first one also gets triggered :upside_down_face:

Everithing else works perfectly, and i can use it to morph two diferent sounds with just one gate, but that wasn’t the idea.
Any idea why this could happen?
Here is a video just triggering with the button, but happens the same when i use a gate.

Thanks in advance for your help!


I think you may have wired the left hand (on the layout) gate in jack incorrectly, the switched input socket. Can you share a picture of your wiring?

Maybe add a switch to have 2 choices :slight_smile: (1 trigger for 2 out, or 2 individual)

Those are the pictures, I don’t know if you could see anything.
As you’ll see the input jack 1 has the switched option (is the only jack thats different to the others)

That would be awesome, the problem is that I cannot trig the first envelope alone, just both at the same time.

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Wiring the switched socket correctly should give you exactly the option dud is talking about.

I can’t really follow your wiring on the pics.

Look at that image, and check that the ‘signal’ contact on your jack is connected through to the diode and the ‘shunt’ is connected to the other jack’s input.

The stripboard layout looks to have them the wrong way round possibly.

Its really hard to tell from the pictures what sort of switched jack you have, but whatever contact the bent bit of metal that touches the tip of your cable is permanently connected to is the ‘signal’ one, and whatever contact touches the same bent bit of metal whenever you don’t have a jack inserted is the ‘shunt’. Make sure you send the right one to the right place, and neither to ground.

It should work so that when there’s no jack inserted in input 1, the gate from input 2 is shorted to your input 1, which will give you a single input ad/ar with two controls and two outputs, and when a jack is connected to input 1 you get two separate ad/ars

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Actually… maybe I misunderstood. Does it only not trigger from the button or from a gate input too?

The diode for input 2 is the wrong polarity on the stripboard layout.

I think that would send the second button trigger back through the first ad/ar when no jack was in the input.

Not sure why your trigger button isn’t working though if that envelope generator responds to the other trigger fine…

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I made some progress!
I put that diode in the way it’s shown in the stripboard (i also assumed it was wrong) and now i can trigger with both buttons!!! But…
When i plug a gate into the first channel (not working one) it doesn’t work and i could neither trig with the button. I triple checked the conection you posted above and it seems to be correct.

Also, i still get both channels triggered by the other. It’s that normal? :thinking:
Thanks for your help!

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Hmm… Ok…

Do both trigger independently with their respective buttons when no gate in is connected, or does each trigger button activate each gate too?

Do you have a multimeter you can use to check continuity? If not it’s time to pick up a cheap one.

Everything you are describing still points me to an issue with the switching jack without me getting in there… is it possible it’s shorting something to ground when the jack is plugged in?

Can you check to see if you can see gate voltage coming in when the jack is inserted?

The reason I think it’s an issue around the jack socket is that if it works from both the trigger and from being triggered by the other gate without a jack in, but then doesn’t work when the jack is inserted… the only thing that’s saying to me is something is going weird when the jack is inserted.

I think ordinary behaviour should be trigger or gate two triggering envelope one only when nothing is plugged into input one.

If trigger one triggers envelope two too, id look for a short on row A and C between the columns 21 and 23 - maybe you haven’t properly cut the traces there.

It also doesn’t make sense that the trigger button for envelope one doesn’t work if there’s something in the jack socket, if I’ve understood that right. I’d say that it suggests the jack being insert somehow shorting the trigger signal to ground. Out of interest if you plug something into jack one, hold the trigger button for 1 down, then press trigger 2 button while still hold trig 1, does envelope 2 still trigger?

I’ve checked with the multimeter everything, no shorts in the cuts, not gate going to ground, same voltages in both jacks…

I think i’ll give it some space and come back to it again in the future.
At least is almost 100% working, two envelopes with just one trigger :upside_down_face:

Thanks a lot for you help!!!


btw I’m not sure if the stripboard version was verified,

in that post :
" EDIT : I am reasonably sure I’ve got this right, …
… I am building/testing the second half now, I’ll correct if there are any mistakes."

maybe re verified the stripboard with schematic

It seems as though the stripboard layout schematic you linked to is incorrect.

If the left input socket is a switched skocket where the two bottom pins are connected when no patch cable is inserted, then the right and left input sockets are connected. An input in the right hand socket would trigger both the left and right AD/AR envelopes, when a connection is made with the switches In combination with the incorrect inverted diode on the right input side, pressing the trigger button on the right hand side, would cause to trigger both envelopes as well.

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When doing it I understood that it was just two independent circuits in the same stripboard. Basically simetrical.
That’s why I din’t understand how it’s possible that they’re cross-connecting between each other.
I triplechecked everything, even disconnected the switch so they aren’t connectet to esch other.
And the same stuff happening.
I think i’ll redo the simple env in two separate boards and connect them simply by the jack.

It seems very doubtful the problem is in the circuit board. It really is two separate circuits on the board except the power connections. Off the board, the jacks are connected so a trigger at the right* jack (or the right push button) with nothing plugged into the left jack should trigger both envelopes; if both jacks have inputs plugged in, each should trigger only its own envelope. If that is not what is happening, I think the problem must lie in the jacks wiring. I can’t see how it can possibly be on the stripboard assuming all the strip cuts are good.

* “right” and “left” referring to positions in the stripboard layout diagram

It’s designed so an input at the right jack triggers both, if nothing is plugged in on the left.

If that is happening, but the left cannot be triggered by its own input, then the problem has to be with the left jack or nearby wiring. In fact I’d say it has to be a faulty jack on the left input; evidently the tip switch connection is working, since the right jack puts a trigger on the left jack output, but there’s not a good connection between the plug and the left jack tip terminal.

But if the left button also doesn’t trigger the left side, that button may be faulty too.

This. This is exactly what I meant in my previous message, but AO conveys it much better. :smiley:

The button in the left side works well till I plug something in it. Then it stops working.
Right side works ok but is allways triggering left side, no matters if there is a jack or not.

I’ll change again the jack and re-check every connection.
Thanks far all