Erica Synths EDU DIY Dual VCA Eurorack Module Kit User Manual
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To try this in practice, grab your breadboard and set up a (very simple) circuit as shown
below. It’s just a 100k potentiometer configured as a variable voltage divider, with an
audio signal sent in via the right hand jack socket. You should then connect a pair of
headphones to the left socket. Since this is a passive circuit, you won’t need a power
supply or battery.
By turning the potentiometer, you should now be able to change the signal’s volume.
With this, we know why voltage dividers are a good fit for manual volume control.
But the
question is: how can we modify them to give us voltage-based volume control?
Well,
if you’ve watched some of my earliest videos, you might already be thinking in a certain
direction here.
We’re looking for a big component here, with a shaft on top. If the pot doesn’t quite fit, try
bending the legs upward a bit. No worries, this won’t break it.
The other elements connecting sockets and the potentiometer are called jumper wires
.
Please
note that these are not included in the kit
.
Though depending on your headphones, the response could be a bit rocky. This is simply
because our passive circuit is limiting the amount of current that’ll drive your headphone’s
membranes.
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