Vactrols Vtl5c3 vs Vtl5c9

hello,
i'd like to know what is the principal feature that make the difference between these two components.
I' made a weak joe optical comp and i've put a vtl5c3 and not a vtl5c9.!!
i have no really sound compression, i can't hear it...
I think it's a logical reason for it doesn't correctly operate.

How could i correct this problem with keeping the vtl5c3
By example: adjust the current or voltage at the input or at the output of the vactrol component .

Thanks for your help :wink:

What about reading the data sheets for those optos?

Jakob E.

The VTL5C3 is unlikely to work in a circuit designed for a VTL5C9. The -9 has a much greater dynamic range, and a cell resistance at 10mA LED current of 150 Ohm instead of 4KOhm for the -3.

To use the VTL5C3, you would have to re-design the compressor signal circuit to deal with higher cell resistances and the sidechain circuit to drive higher currents. Even then, the performance in this application would not be as good as with a VTL5C9 because of the dynamic range differences between the two parts.

hello,
thanks Boswell, i'm completely agree with you.
after many tests and modifications the result is the dynamic range of the vtl5c3......the sound at the output is dirty when compression is high
Solution : buy new vtl5c9 :wink: