# Caesar Chorus EQ modifications



## calculuscore96 (Jan 13, 2022)

Both Caesar's I have built are very close to the Julia, but retain slightly less bass and low mids than the Julia. Could just be combined tolerances, but I want to beef up the effect signal. I know that in a CE-2 schematic the two 100pf caps function as low pass filters, should I decrease/increase the corresponding 100pf caps in the Caesar? Anybody know what other key parts might be most responsible for sculpting the eq? Thinking about just socketing some stuff


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## Stickman393 (Jan 25, 2022)

Good read on the CE-2 circuit, which the Julia clearly was based off of.






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You'll be able to plug component values into the equations there to see how changing individual components can affect the frequency cutoff and gain of each filter.

Those little 100pf caps don't appear to be the best place to focus your attention, if I'm reading this article correctly.  Parallel paths where one is equal to zero...I might not be totally wrapping my head around this.  Maybe someone else can chime in 

But, the pre-emphasis filter can be tweaked by adjusting R9, S10, R11, & C4.  Increase C4 alone, and you shift the frequency curve a bit lower, boosting and shelving from a little further down.  But the pre emphasis and de-emphasis filters are meant to cancel each other out in this scenario.  You might be able to get some results by shifting the de-emphasis filter range down a bit...couldn't tell ya.

Honestly, I'm curious what would happen if you bumped R16 up a bit in the anti-aliasing filter.  That would certainly feed more low end into the BBD...but how much would actually make a difference?  Shoot, I dunno.

First time engaging with the math here...learning like everyone else.


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