Balancing the "WHAT Compressor"

[JanusRec]

Hello everybody,

I'd like to build one of DeeT's What Compressors, as the sound samples are amazing and it is really cheap and easy to build.
But to make it really useable, it needs a balaced input and output section. For the input a OPA2134 should be fine. For the output I'd like to use DRV134.
Now my question on the schematic there are lytics (C3, C4) in the input and output sections. What are they used for? Can I get rid of them/ reduce their seize? I guess they are for DC protection, but why do they have to be that huge?

Thanks for your help.

What I am also planing to do:

• Replacing the MC33178 with Opa2134
• Replacing the TL062s with TL074 to safe space
• Extending the gainbandwidth to 100kHz - all opamp filter caps are calculated for ~ 20kHz on the current schematic

And before you ask: I'd use search function and didn't find anything useful...


Sebastian

 

[[silent:arts]]

look at Volkers ideas:
http://www.nrgrecording.de/nrg/viewtopic.php?t=1528

(no, not me, that's another Volker)

best
Volker

 

[JanusRec]

Danke ;-)

 

[Kir_For_Pleasure]

looks like my next diy is to learning german 

 

[volker]

Never mind, unless you want to read Goethe and the likes in its original... erm, beauty .
I'll post the building documents here as well, as soon as my proto is up and running.
Still some time to wait, I haven't ordered the pcb yet.

 

[Kir_For_Pleasure]

Göte in swedish 

 

[PRR]

> lytics (C3, C4) in the input and output sections. What are they used for? Can I get rid of them/ reduce their seize?

They say "M" but C3 must be 1 microFarad, C4 is 33 microFarad, 16V. Both are smaller than a pencil eraser. They are not absolutely essential, but you do need to block DC "somewhere" in an audio path or the milliVolts make trouble.

You could make R1 R2 47K and then make C3 a 0.5uFd film cap. If C4 only drives an output buffer with high input Z, it too can be a film-cap.

 

[SIXTYNINER]

8)