Seen this video earlier today -
I know @Bitnik just got a Crave, so I figured I would post this up 
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The frame before it got to the build, bandwidth choked and I couldn’t see a thing. What’s he got there, a 4011-based circuit?
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I like the idea, but if I want something like Crave but with more oscillators I can just write a few lines of C++ or SClang. There is literally nothing that can be done in analogue hardware that cannot be done infinitely better in software on an inexpensive modern digital system. But the experience is limited by our very primitive interfaces with digital systems.
What I like about Crave is the immediacy and the physicality. It’s a musical instrument and I want to treat it as such. I don’t want to turn it into an electronics project.
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Ha, what I like about the crave is that the CV-in and outputs invite one to add electronics.
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Proceed carefully. Check the limits in the manual or you’ll have a lot of spare parts instead
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Got the Crave a few weeks ago and Got The MS-1 earlier this week, gonna have a go at making one of these.
thanks for the link 
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Hi, I’ve had a look at the schematic and I think the 47 uF input capacitor’s polarity (the flat bit of the symbol denotes + and the curved part -) is not correct ( I believe this is C4 ). That is of course assuming this is an elco ( Ha, otherwise it would be huge 
). The plus side of the capacitor should be at the signal supplying side ( this is where a voltage comes from ) and the negative side should be connected to the resistors that leads to the transistor’s base ( which is always the low voltage side of this chain of components ).
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I might leave this then until it is verified! 
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It is very unlikely to blow anything up. This is only of importance if you know that the output of the module preceding this module has a DC offset that is positive. But any preceding audio module should be decoupled as well, so …
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Blow up? No. But experience tells me that even linking different manufacturer equipment needs to be careful. Just measure and check against the ratings before you plug in.
I’ve had weeks diy work fried by a fault in the phantom power in a mixer.
Almost lost a Moog etherwave to a cheap power supply that was way overpowered.
I’m sure it’ll be ok but you only have to check once to be sure.
If it helps, tell yourself I’m making you do it.
Why do I care? I’m just proper jealous of you having a crave to play with 
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In this case only the capacitor itself is at risk.
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Yup. Still… I’m just a cautious old fellow. Have fun. Sorry if I sounded hysterical. As you were.
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I’m about to give it a whirl. I’ll keep you informed.
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Yeah, why would a VCO have a DC offset?
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A VCO wouldn’t have a DC offset, but you can of course connect anything you like to this circuit and then there might be a DC offset…
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True. But it might be either sign.
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I suppose the truly paranoid might put an optoisolator coupling between the DIY circuit and the expensive toy.
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You are absolutely correct!
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WARNING WARNING WARNING
I’ve just built this on a bread board. And it works like a charm and sounds great. Just to make sure, I checked the input specs of the Crave. It can take from -5 to 5 volts on its Ext audio input and this circuit will output a signal between minus half the voltage it is powered by and plus half of the voltage it is powered by. So if you power it at 10 Volts max you don’t move outside the specs of the Crave. But if you go higher than that you will! Maybe there is some circuitry inside the crave which protects it from high input voltages which would not be out of place given that it is a system that invites people to put all kinds of signals in it and CV voltages are not particularly well defined. I don’t know. So if you power it at Eurorack standards, i.e. 12 Volts, it is wise to replace the 100k and 1kOhm output resistor by a trimmer potentiometer and connect its center point to the output and set the min and max voltage to not go beyond -5 and +5 Volts (you’ll need on oscilloscope to do that).
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