Op amp make up gain for NewYork Dave EQ

[diko2]

Hi everybody,

I've just made a make up gain for my NYDave EQ.

reminder NYDave EQ:
http://groupdiy.com/index.php?topic=45515.0


I use a simple inverter op amp to do this:

I was wondering if i need a blocking cap between the EQ and the Op amp?

Thanks

Morgan

 

[diko2]

Really nobody?

 

[12afael]

you are using a bipolar power supply? the passive circuit doesn`t have DC BUT you will have a small current in the input of the op amp. I`m not sure if that current is good for inductors provably it is negligible.

 

[diko2]

Hi 12afael, thanks for your help. It's always difficult when passing from theory to "real world".

Yes indeed i use bipolar supply.

Maybe i just can throw a blocking cap there in case.

In the same way, i'm also wondering if it's a good thing to put a cap in the feeback loop to get rid of the unwanted HF (oscillation?)?

Do designers always put one there just in case? What is a reasonable frequency cut point? 30 Khz?


Thanks a lot.

Morgan