GSSL HELP THREAD!!!

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I am going to do a test today with the jumpers, but if the VCAs were bad(or at least the one in the sidechain), which it sounds like they should be, shouldn't the unit not be compressing and the ratio / attack / release all not be working? Maybe I misunderstand the circuit?
I did the test and here is my report:

When jumping pins 1 and 8 on the left and right VCAs, the compressor still behaves as normal in terms of meter reading etc, but there is no sound output still.

When I do the same jumper test on the sidechain VCA, the meter no longer behaves normally. I think this answers my question that the metering would not work with a faulty VCA, so does this mean my VCAs are actually OK, is there any other way to test?

Moving forward for next steps, I notated that pins 1 and 8 on the left and right VCAs are all seeing around 7 volts (the other 6.8).

Let me know what else I can test to narrow down where the signal goes bad!

Thank you so much
 
You had checked for correct DC voltages +/-15V and +/-12V on all IC socket pins before inserting any of the ICs, right ? If not, maybe it's time.
 
You had checked for correct DC voltages +/-15V and +/-12V on all IC socket pins before inserting any of the ICs, right ? If not, maybe it's time.
I did not. I followed the “beginners guide” which only had me check that I had 15V coming off the toroid before installing ICs. I’m working with a 95% understanding (maybe 50% of the actual circuit) and a strong ability to follow directions which, I guess is why this build mostly works. Thanks so much for helping me

Just To confirm i understand….I should be checking the pins on each IC that are V+ and V- ? And looking for them to be +/- 15V or +/- 12V? How do I know which should be which?
 
Search net for datasheets.

Or search for

'"IC number, eg. 5532] pinout"
under /mages/

sidechain 12V
audio path 15V

Check all socket pins.
 
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Switch to "print" view (top right) and search using "find in page" or search function of browser of your choice.
Hi, I'm new here, and I can't find the "print view"... 😖 Where can I find it?

I've built a GSSL Kit from PCB Grinder, and I have 2 issues.
The right channel add a lot of gain (about 12db) and the ratio switch works backwards. Sending a sine wave@500hz and setting the threshold to a -10db GR and 2:1 ratio, changing to 4:1 and 10:1 the GR decreases (-8 and -5 respectively).
 
The gain is most probably because of a wrong resistor

For the ratio, we discussed this many times before in this thread - it's probably OK (ratio switch changes both ratio and threshold).

/Jakob E.

Hi, I'm new here, and I can't find the "print view"... 😖 Where can I find it?

I've built a GSSL Kit from PCB Grinder, and I have 2 issues.
The right channel add a lot of gain (about 12db) and the ratio switch works backwards. Sending a sine wave@500hz and setting the threshold to a -10db GR and 2:1 ratio, changing to 4:1 and 10:1 the GR decreases (-8 and -5 respectively).
 
Hi Jakob, thanks for the answer.
So the ratio affect also the threshold. Ok, so maybe is not a problem.
I'm still looking for a wrong resistor, but I haven't found it yet.

My main question is, how I can switch to "print view"? I can't see it.
GrDIY.PNG
 
I'm confused.
yesterday I measured every resistor with my DMM and they are all correct.
So I removed the right 5534 to check voltages and, put it again in place.
bum. everything ok. the audio enter at -12db and return at -12db.
How is it possible? A chip that is not in perfect position can boost the gain?

I don't know. But now my GSSL works fine, adds the desired amount of distortion and glue together every instrument in the mix.
This is my baby
20210916_183200.jpg
 
I don't know. But now my GSSL works fine
Cool :)

However, take a look here:

Untitled.png

That pin circled in green should really be connected to chassis for safety reasons (your/user safety).

Also curious about what the jack does. Difficult to discern where it connects to. Is that for some sort of grounding? Earthing?
 
ah oh... that photo was a wip. It's not the state of the art.
The earth is connected and the jack is for external SC, in the photo is only grounded, the signal wire is missing.

Today I tried also to render a mix that I made ITB, passing thru the GSSL in bypass mode, and is a good way to add that analog-feel.
 
I'm almost finished with my GSSL build, but when the unit is set to 4:1, the meter pegs hard right and it doesn't pass audio. 2:1 and 10 work perfectly. I've traces the circuit with an ohmmeter around the ratio switch, but everything seems to be normal. Any tips for what could cause this?
Thanks,
Craig
 
You also checked resistor/diode ratio network for solder blob and or diode orientation ?
Yes, the diode is oriented correctly. Also can't measure any extra connections in that area.
Messing with it some more, it doesn't slam the meter every time I switch from 2:1 to 4:1, but when I start to switch to 10:1, the meter pegs, but goes back to normal after I switch all the way to 10:1. Does this sound like a faulty switch?
 
Well after a year after ordering I think I got mine up and running. After a lot of troubleshooting, having to source new VCA’s after the THAT’s that came with it were faulty, drilling out a couple pads to make the DBX’s fit and soldering components to the bottom, and replacing a voltage regulator I shorted….Signal is finally passing, the meter is moving, and it’s definitely compressing. So a small victory for my second build, and I do feel pretty damn great. Had a couple questions though and I apologize if I missed them in the thread: There’s definitely a significant volume boost when running signal through, even with no compression and the output at the minimum. Also, it doesn’t quite have the snap that I’ve known from SSL’s, not that I’m trying to have an exact copy. The compression feels spongy and can’t seem to find the happy medium between barely noticeable and way too much. I’m firmly willing to admit I’m way overthinking this with my head so far deep into getting this things up and running, but something just isn’t sitting right and I can’t quite put my finger on it. Anyone else have similar experiences. That said, definitely took a major step forward with this build. Couldn’t have done it without the resources and great advice here. Going to play with this a while before potentially adding a cavendish.
 

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Yes, the diode is oriented correctly. Also can't measure any extra connections in that area.
Messing with it some more, it doesn't slam the meter every time I switch from 2:1 to 4:1, but when I start to switch to 10:1, the meter pegs, but goes back to normal after I switch all the way to 10:1. Does this sound like a faulty switch?
Hi folks just bumping this to see if this sounds like a faulty rotary switch.
 
Yes, maybe . I'd check switch for continuity

In two posts, it looks like you described two different problems, maybe not : one was 'not passing audio at 4:1' setting, the other one was needle pegs/slams. Unit shouldn't do either.

Is is always the same problem ? Repeatable or erratic?
 
Yes, maybe . I'd check switch for continuity

In two posts, it looks like you described two different problems, maybe not : one was 'not passing audio at 4:1' setting, the other one was needle pegs/slams. Unit shouldn't do either.

Is is always the same problem ? Repeatable or erratic?
I really appreciate your help!

When the needle slams to the right, it doesn't pass audio. Sometimes when you turn the switch just right, or thump the knob, the meter settles back to normal, and it passes audio. If you do go from 2:1 to 4:1 and the unit behaves normally, if you ever so slightly touch the ratio switch the problem comes back.

Strangely, with the meter pegged and the unit not passing audio, there is continuity between the pole of the switch and the 1.8M resistor it's connected to. The resistor doesn't show continuity to the nearest resistor and diode, which indicates there isn't a solder bridge.
 

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