Anderton
Try this: Hold Alt+Ctrl, click on the PC-76 meter, then drag up/down. The little meter screw turns.

I can get the screw to turn without the Alt+Ctl.
 
Thanks for this thread since I'd forgotten about the screw-light thing.  It allowed me to light up my bland-looking PC4K. Much better.
 
And also to learn that PC-76 and PC4K can only be used one at a time in PC.
 
 

Beepster

...wicked
I thought I recalled that it did actually do something, HF bias or some such. But I may be recalling wrong.
 

Are you thinking of the CA2A? That screw alters how the compressor affects frequencies or some such. I fiddle with it all the time because it makes a subtle difference on really frequency rich signals like distorted guitar (to my ears anyway). Not so much on less chaotic sounds.

If you are referring to the R37 screw, it adjusts the high frequency response on an LA2A and most emulations. I find the effect is easier to hear when you sweep that control. Even on the real deal it is a subtle difference.

ampfixer
 
If you are referring to the R37 screw, it adjusts the high frequency response on an LA2A and most emulations. I find the effect is easier to hear when you sweep that control. Even on the real deal it is a subtle difference.

Yup. Subtle but really worthwhile. It has so few controls anyway it's pretty easy to give the screw a twist just to dial it in for the specific source. It really does depend on the material feeding it.
 
Can't even describe exactly what it does. It's like... the "slightly better sounding" control. Like some weird variable comb filter control that hones what the compressor works harder on.

Beepster

ampfixer
 
If you are referring to the R37 screw, it adjusts the high frequency response on an LA2A and most emulations. I find the effect is easier to hear when you sweep that control. Even on the real deal it is a subtle difference.

Yup. Subtle but really worthwhile. It has so few controls anyway it's pretty easy to give the screw a twist just to dial it in for the specific source. It really does depend on the material feeding it.
 
Can't even describe exactly what it does. It's like... the "slightly better sounding" control. Like some weird variable comb filter control that hones what the compressor works harder on.

Turned one way and the compressor works equally on all frequencies, turned the other and it compresses the higher frequencies more.

Ah yes, the R37 screw, sorry!

John
It tightens or loosens the screw. 

This was what I was told when growing up

Weird that turning it on the PC-76 interface changes the light on the PC4K.  Turning it on the PC4K does nothing.  What an odd way to implement that.

Ask Monday at the water cooler.

It's an easter egg that was put in to the module as already mentioned. Does nothing to the sound :)

I think you're referring to the PC4K bus Compressor "change the color" thing. I'm talking about the PC-76. I don't see or hear anything from turning the meter screw.