Gain changing tricks – Erica Synths EDU DIY Dual VCA Eurorack Module Kit User Manual
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GAIN CHANGING TRICKS
That being said, the emitter resistor is not the only variable we can mess with to influence
our amplifier’s gain. We’ve got two more options here.
First, we can adjust the value of
our collector resistor
Because if we increase it, then we reduce the amount of current that could potentially
flow through it. Now, since this does not a
ff
ect the transistor’s operation, the collector
current swing will stay the same. Which means that essentially, it’s swinging across a
larger portion of the full potential, netting us a bigger voltage swing at the output. There is
a hard limit here, though.
We can’t just keep increasing the collector resistor’s value
in hopes of unlimited additional gain
.
Because at some point the potential amount of current will drop below the set collector
current,
starving our transistor of power and distorting – or even killing – the oscillation at
the output.
You can try this chapter’s circuits in a simulator. I’ve already set them up for you right here:
you can change all values by double clicking on components.
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