Using the Pico Compressor Gain Reduction Meter with the GSSL

[radiance]

I checked and it does track linearly. Also, your values work very well.
Thanks!

[quote author="RogerFoote"].

If I did wrongly assume that, my apologies. I can make it right for you one way or another, for sure!

Thanks for helping out here!

Roger[/quote]

You already made it right by answering my questions :thumb:

For me, it's these little things that form the learning experience.

 

[mrcase]

Hey radiance!

I´m about to finish my second gssl and want to use the same meter as you did.
any chance you remember which resistor values you`ve changed to get it working properly? 
thank you so much!

martin

 

[radiance]

No, I'm sorry. But you might want to ask this at the pico forum...


http://www.proaudiodesignforum.com/forum/php/viewforum.php?f=1

Roger should have that info somewhere...

 

[mrcase]

thank you. gonna check that out then! btw. do you like the led meter in your comp?

 

[radiance]

well...it can be very precise (1/2 db per led) but I like the sifam director 14 ppm beter..

 

[beatnik]

Has anybody succesfully used the pico meter in the gssl? it's not so clear to me how to connect it and especially how to calibrate.

Can anyone help please?

I connected it to the main board where the 2k resistor was (jumpering it). with the 10dB resolution (4k75 resistor) meter doesn't show the correct amount of gain reduction compared to the vu meters on the output.

Is there some voltage point I can measure, for example sending a signal in and checking voltage going into the input of lm3914?

 

[weiss]

sorry for bumping this old thread but is there any way to get hold of this LED GR meter board ??? Ideally it should have 15 - 30 LEDs
Would something like this this be able to show GR instead of VU?
Not sure if the VUPPM by JLM would be suited?

 

[dogears]

sorry for bumping this old thread but is there any way to get hold of this LED GR meter board ??? Ideally it should have 15 - 30 LEDs
Would something like this this be able to show GR instead of VU?
Not sure if the VUPPM by JLM would be suited?

The meter doesn't know whether it is showing VU or GR. It just knows a voltage reference, and you set the reference voltage by the resistor ladder between each input on the LED driver.

I was fiddling around with something like this because the LM3916 and so are all obsolete. I actually made a PCB but I had a boneheaded error (since corrected) so my PCBs were garbage. I think this schematic is correct. If anyone wants to take a look and check it, I'd be glad to share the PCB file on EasyEDA for you to order for yourself.

I got the peak detector from some datasheet or other, I forget now.

If you wanted to have more LED points, you could use two of these, for example, with different resistors for each (one covering the upper amounts of GR and one covering the lower). For GR, it depends on what you're using for GR - if it's a VCA, there's a voltage point on the sidechain...maybe after the ratio pot - or at any rate, immediately before any final gain to the VCA control port. That would probably be a *linear* scale for your resistor ladder.

 

[dmp]

sorry for bumping this old thread but is there any way to get hold of this LED GR meter board ??? Ideally it should have 15 - 30 LEDs
Would something like this this be able to show GR instead of VU?
Not sure if the VUPPM by JLM would be suited?

The Pico SEII takes the GR voltage after the ratio pot. It goes to a unity inverting opamp buffer (gain=1)  and then to a range buffer.  The meter range selection of 10 or 20 dB routes the GR signal to an inverting opamp buffer with either gain 20 (for range 20 dB) or 40 (for range 10 dB).  This signal goes to the meter input (pin 5 LM3914).  The meter uses two LM3914 stacked to make the 18 LED meter.  It looks like the meter is set up to have 0-2.5 V full range.

I would think you could use that meter - you'd just have to tweak the signal level to have the GR correct for whatever you want the full range to be.

 

[iprovlek]

Here is the link for kit where is one of PCB for GR meter of original That4301 compressor which is similar to Pico compressor!!!

This is whole kit for bass guitar kit, part of kit is just for GR meter....

https://www.musikding.de/Pumpernickel-compressor-kit

 

[iprovlek]

Here is scheme...

 

[weiss]

Awesome!
Thank you guys for all the input and quick responses!!