Forsell Comp plus Tape

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Potato Cakes

Well-known member
Joined
Jul 1, 2014
Messages
2,258
Location
Nashville, TN
So what we did was take a harmless, innocent Forsell board, then force fed it two different, selectable and bypassable tape Color modules, then bread board a slightly more complicated relay station, then jab a bunch of potentiometers to figure out where to set the gain for U5 (sidechain signal amplification) and the feedback for the DOA output. And you get this thing. I still have to change out the VU meter and tidy up the wires, but it's done and sounds really different. The compressor is too grabby for the program material I was testing it with, but this was designed for individual tracks. The tape insert is passively mixed with the dry signal and there was a fair bit of trial and error trying different resistor values so there wouldn't be a massive jump in gain feeding the compressor going between wet and dry.

I'm using a 10 segment LED bar for the gain reduction which seems to track very well with the actual gain reduction.

The stepped ratio values are borrowed from one of the guys on the old Forsell thread. I'm not sure about my selections, but I don't have a way of doing precise gain reduction measuring with sweet chart action. The different ratio settings are changing the compression characteristics, so it's doing something, but probably not exactly what is labeled on the panel.

The Color modules are the 15IPS and the Distorastudio. They are really fun and definitely create the sounds they are designed to emulate.

I think the threshold pot I'm using needs to be changed to linear as I don't get much action towards the lower threshold settings and then it hits a point where there is much more movement in the gain reduction as it relates to the threshold level. Or maybe I'm using a linear already. I'll have to look. It still works.

All that's left is to finish mounting everything and clean up the wiring, but will be for later as I should go to bed with a DIY win. I thought this was share worthy with everyone here and to say thanks for letting me be apart of this community where I have been able to learn how to do crazy stuff like this.

Thanks!

Paul
 

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Potato Cakes said:
I think the threshold pot I'm using needs to be changed to linear as I don't get much action towards the lower threshold settings and then it hits a point where there is much more movement in the gain reduction as it relates to the threshold level.
There are many situations where the ideal taper is between a linear and a log; it is generally possible to modify the taper by loading the wiper to one end via a suitable resistor, or to add a padding resistor (generally at the bottom). That is called law-steering; several threads related to that can be found in this group.
 
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