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Build help and troubleshooting => CP4500 Stereo Bus Compressor => Topic started by: txshonk on April 15, 2023, 06:41:43 PM

Title: CP4500 Ratio Reversed?
Post by: txshonk on April 15, 2023, 06:41:43 PM

I was setting up PCB A up and all seemed to work well from test guide steps.  I then started testing over features.  I have not installed PCB B yet (i dont believe PCB B missing would create this issue).  But as I pass signal into I am seeing the output increase as I increase the ratio.  I would expect an inverse relationship

In looking at the schematic all the resistors and diodes around the ratio portion of the circuit seem good.  Does the rotary switch have be positioned in a certain way? Could it be i have the ratio switch 180 degrees inverted?

Let me know if anyone has any suggestions.

Dave

Title: Re: CP4500 Ratio Reversed?
Post by: JPK on April 17, 2023, 09:12:43 AM

This is normal. It is true for small gain reductions. When you lower the threshold it changes direction.
This is because the ratio switch also affects the threshold level. In the end, the ratios are correct.

Title: Re: CP4500 Ratio Reversed?
Post by: txshonk on April 22, 2023, 07:48:25 PM

Thanks- I can confirm when I lower the threshold to more extreme levels I see exactly the behavior I was expecting.

Thanks!!!

Dave