GSSL HELP THREAD!!!

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THAT has better specs

but coolaudio, being sloppier, may have that "sheen" that some associate with the ssl4000

Most of the sound in this unit is sidechain function, not parts


..yes - the that 2150/2180 series are also marked like this:

https://www.thatcorp.com/datashts/THAT_2181-Series_Datasheet.pdf

/Jakob E.

edit: and no, usually only the vcas themselves gets damaged by this
Hello !

Got the new 2181's today and soldered them in. I also reverted to vanilla setup for now.

Now I have some other weird behavior. there is sound, but also only the makeup pot works in ON-position , like it should.

But here it comes, There is no compression at all. no Meter movement. But then I saw that the power led of the switch got lower , more dimm after a minute or little more. I turned the Unit off and on again , and to my surprise the Compression , the meter and everything , the whole function of the device fades in , like in a swell , and goes away again . like a big wave of normal behavior :) Wtf is that ??? is it some Power thing, capacitors , or ?? I don't get it . 15v on + and - stays constant all the time.

I could also upload a short video of the behavior if needed,

thanx again !
 
Thermal shutdown of 12v-line, we've had this before. Search?
I searched, and also heard before that the led can cause problems. should I try running it without the leds connected to check ?

UPDATE: Ok, disconnected leds. Even got back to the original stepped switch from ur ssl.pdf. just to get the pushbutton confusion out of the way for now ;)

Meter shoes movement, makeup is working. but no compression, threshold Poti no effect at all.
that's so frustrating... :)
 
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Little jumper on front assembly board is installed? Not sure tho all board versions still need it.
 
after a little brake I got back to it

ok, I checked everything again, I also changed and used the additional resistor, trimmer and jumper for the THAT2181C. still the same Problem. bypass works, audio comes thru. only makeup gain change output sound, also meter reacts to only high input level as it should. but I think this is adjustable via trimmer, right ?

However. I#m on the end of my knowledge here. And it feels more like searching in the dark here.

I can't spend so much time on it, and im afraid that means it will collect dust in my shelve....

So,... I rather give it away to somebody who is more experienced with trouble shooting. If someone wanna buy it from me, I#m sure we figure out a good price. As u can see in my pics before I have a white front panel and knobs from don audio/frontpanels.de. and super sidechain mod.

so sad, I managed to build the stereo Pultec EQ and the stereo Calreq EQ successfully

Anyway thanx for all your help !!!! and hopefully my unit finds a new home and gets back to working status asap :)
 

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20 years of GSSL help thread (!!) today​


Hey everyone,

Today marks an extraordinary 20 years and more than 9000 posts since we kicked off this GSSL Help Thread! It's been a wild ride, full of learning, troubleshooting, and community spirit. From PCB issues and power supply woes to meter selection and VCA consistency, we've tackled it all together.

Common Fixes:

PCB Troubles: Verify part types, orientation and placement.
Power Supply: Ensure correct transformer and regulators.
Meters: Use linear 1mA FSD types.
VCA Matching: Don't mix different types. And note orientation (one is oriented the other way around!!)
Missing links: remember to put in the wire links at the pcbs - both main and front pcb
Circuit bending: Start out by building the "vanilla" version, then when it works, add mods.

Thanks for all your contributions and here's to many more years of DIY success!

Cheers,
Gyraf
 
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Turbo, HPF, CRC and mix/blend (and whatever else I don't know about) need to be integrated into a newly designed layout/board. People can still learn without putting them through unnecessary pain and suffering! ...and a big mess, imo!
 
Hi,

I just built the GSSL and supersidechain but it’s not working.

The LED lights up, sound passes through, the makeup pot works but there is no compression, unless I set the super sidechain to TM - that’s the only time the compression works and can be visualised by the meter.

Any ideas what’s going on? I’ve tried adjusting all trimmers but have had no luck

EDIT: I disconnected the main board from the SSC board and that is functioning as it should. Seems to be an issue with the SSC board - anyone have any ideas of where to start?

I'm using the SSC with a relay, and a rotary switch connected to SW to and RET from here:

https://proaudiogc.com/en/gssl-super-sidechain-filter-with-relais-in-out-pcb
 
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I finished my GSSL and when i checked the frequency response with plugin doctor I'm getting a 7 db spike/bump at 50 Hz on both channels that stays when I Bypass too. It doesn't change as I'm moving the front controls. I run out of ideas about what to check and would appreciate some brainstorming about what would you suspect that might create this bump. My build has stereo supersidechain, turbo and cavendish MOD's too. If you guys suspect the MOD's I will take it to the other thread, just need some help what to check for.

TGS: the link is https://groupdiy.com/threads/gssl-add-on-help-thread.65232/
 
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I finished my GSSL and when i checked the frequency response with plugin doctor I'm getting a 7 db spike/bump at 50 Hz on both channels that stays when I Bypass too. It doesn't change as I'm moving the front controls. I run out of ideas about what to check and would appreciate some brainstorming about what would you suspect that might create this bump. My build has stereo supersidechain, turbo and cavendish MOD's too. If you guys suspect the MOD's I will take it to the other thread, just need some help what to check for.

TGS: the link is https://groupdiy.com/threads/gssl-add-on-help-thread.65232/
I would try measuring in REW. I get funny results from plugin doctor measuring hardware sometimes.
 
There's no realistic error mode of this compressor where it turns into a resonant bass boost.

Have you listened to it? +7 at 50Hz is kinda obvious if real.

And if real, I'd look into latency+mix in your A/D D/A system, I would not expect it from the comp
 
I would try measuring in REW. I get funny results from plugin doctor measuring hardware sometimes.
I scanned with REW and yes that bump doesn't exist so it was some plugindoctor artifact. Thank you craigmorris74 and Jacob for the help! It's a beautiful compressor and the cavendish mod even though really tricky and head-scratching to figure out the correct way to do it was really worth it too as you can push in to the compressor now and get some awesome color.
 
Hi everyone,

I'm using a GSSL with a turbo mod and 202c VCA's.
I have a volume difference between the two outputs of about 0.5 Db.
How can I balance the outputs ?

Concerning the output level, this may be a silly question but the GSSL does not work at line level, I have to go through the preamp of my sound card in MIC and activate the PAD attenuation, without PAD attenuation it completely saturates the input of my sound card ... Is this normal?

Thanks in advance ;-)
 
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