Hey Guys, on Sams AD/AR Module on Stripboard there is +12v, GND and -12v. Do i need the -12v and if , how do i get it?
Greetings from Germany
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Yes, the TL072 requires ±12V.
You get it from a power supply that supplies it. Most synthesizers have such a supply. Look here for information about synth power supply choices.
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Which stripboard layou have you built? Link?
But as AnalogOutput says you will need a main power supply. This will be required for most of the modules you will come across as the audio signal is a waveform with both a Posative and A negative portion.
Rob
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I mean, maybe you could substitute an LM358 for the TL072 and get it to work with a single supply.
What are you planning on doing with this circuit? Generally envelope generators are used to control voltage controlled amplifiers, and they usually need ±12V too since, as @twinturbo says, they usually deal with waveforms on both sides of 0V.
I assume:
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Yes, you are faster than me 
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I started to build some little circuits , APC and WSG and now i want to build Sams Modules and -12v is totally new to me, i know AC 220v and DC + and -. … so i have to build/buy something that can handle + and -. … Its not that easy everything looks
You may find this thread useful:
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An envelope generator is sort of an odd module to be starting with. Nothing wrong with it, just that it doesn’t produce any sound on its own; it’s used to control other modules, typically VCAs. Which also produce no sound on their own.
You might find it more satisfying to build an oscillator first such as this one
and when you’re done you’ll have something you can listen to and say “Hey I made a thing that works!” without needing other modules for it to work with.
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Of course i’ve build something that sounds before. A couple of Sams super simple Oszillators, an APC, the Weird Sound Generator from MFOS and now i’m waiting for the AS3340 to build Sams 1v/Oct VCO but I guess I need -12v for it too, right? I´ve build the AD/AR because of the parts. I had them here and so i´ve build it and I think its good to have it. The APC and the WSG run with +12v or +9v and GND and that’s why I didn’t think about the -12v. So the next step should be my Power Supply
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Sure, my point was just that you won’t know if your EG works until you have another module for it to work with. (I mean, the LED will light up, but that’s it.) An oscillator audibly works or not on its own. And then a filter can filter the oscillator, a VCA can vary the volume of the oscillator, an EG can control the VCA (or the oscillator for that matter), and so on. But any of those without an oscillator or other audio source, or in the case of the EG a voltage controllable module, won’t do anything interesting on its own.
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Yes, that’s damn right !! 
Got it, to start with modular synthesizers, it’s the worst part ever :). Still, it is good to have it 
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I made this, but I’m using a frequency Central power supply. Works like a charm! Going to need that negative voltage if you want other modules, may as well get yourself a power supply next.
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Thanks a lot ! Yes, I just looked at Frequency Central’s PSU and it will be my choice.I will order the one with 8 connecters they are enough for a couple of time i think. And if not the connector strip can easylie been build from old computer Cables. Now i have to look for a cheap AC/AC Wall wart from a shop that sends to germany.
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Oh yeahh, THX a lot, that’s it! With this PSU, the Frequency Control circuit board and the components, it costs just under € 30 which is great! Thanks again!
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I have the Frequency Central unit too. Easy enough to build in little time.
Rob
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Check this thread for the associated videos and a BOM for cheap.
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Extreme good work! Thanks a lot !
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