Please help to identify this built GSSL

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LB82

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Hello,

This is my first thread here. I've got this already built GSSL compressor and after reading GSSL related threads as much as I could I'm still having problems to understand how it was made. I am not a tech/engineer, I just play music and mix, I can barely solder a cable.

I don't undesrtand if it has the turbo pcb installed or not, I've also read about the different vca that can be used and I see that this has 2 DBX 2155 and 2 THAT 2181 B, which I think is a combination I've never read about in this forum.

I attach some pics here, I appreciate any help/suggestions and I can make more pics if needed.
Thanks!
 

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Gustav

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It looks like someone did a board layout with the turbo mod implemented.

The 2155 are most likely used in the side chain, while the 2181 are used in the signal path.

Gustav
 

LB82

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Thanks Gustav,

When using it on a mixbus I felt it narrowed the stereo image more than some other stereo compressors I have available, so after reading on this forum about the turbo pcb mod I thought it was narrowing the image because of the lack of that mod.

What is your personal opinion on this layout? Do you think it's a good idea?
 

moamps

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Radioman maybe.
215x are in signal path, IIRC.
 

Gustav

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Thanks Gustav,

When using it on a mixbus I felt it narrowed the stereo image more than some other stereo compressors I have available, so after reading on this forum about the turbo pcb mod I thought it was narrowing the image because of the lack of that mod.

What is your personal opinion on this layout? Do you think it's a good idea?

I think it looks awesome, you have a great unit, now go make music!

Gustav
 

amplexus

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Jan 11, 2018
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This design critically lacks some kind of safety grounding or double insulation.
No earth ground, all the boards hung off sticky backed zip tie mounts that will dry out and let go, zero attention to lead dress, hacked in diodes instead of the correct fw bridge, and wtf is going on with that to220 reg in the middle of the board??

Sloppy, likely unsafe build…. “If it sounds good it is good” only gets you so far imo…
 

Rob Flinn

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The GSSL sounds wider without the turbo mod because it compresses the bass end twice as much. To my ears the turbo mod makes the compressor sound fuller.
 

LB82

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The GSSL sounds wider without the turbo mod because it compresses the bass end twice as much. To my ears the turbo mod makes the compressor sound fuller.

I have a couple of thoughts about that now that I know that the sidechain is stereo,

The first is that the compressor's sound is very mid forward, so the processed material may be perceived as "smaller" but it is also tighter and translates very well.
The second is that the compressor's behaviour is really "grabby", even at 4:1 it almost react like a limiter when hitting the threshold.
If not used carefully the transient will be really "stopped"and the material will lose depth.
So maybe the whole thing is a matter of "depth" instead of "width" and most importantly it is caused by user's error.
All this happens when using the compressor later in the mix or in mastering and pushing it a little more, if put on early in the mix you go "hand in hand" with it and there should be no such problems.


Sorry to diverge from the technical discussion, just wanted to give my point of view to the user
 

Rob Flinn

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I don't really understand what you're saying.

It's my understanding that with 1 sidechain L & R are mixed then hit the sidechain, therefore things which appear central hit the sidechain twice. In turbo mode L & R each have their own sidechain & the sidchain that isputting out the highest level is is the one that is fed to both L& R VCA's. Therefore sounds with quite a bit of energy (like bass) get compressed more. To me the effect is that the bass sounds light & the high freq content sounds pushed wide. i.e scooped in the middle. My GSSL is switchable & I literally never use it without the Turbo mode.

Maybe the reason your unit is grabby is because the turbo mode isn't implemented right or you have a wrong component somewhere. As Moamps says your box lacks some basic safety features, showing a lack of understanding by whoever built it. This maybe a clue as to why it doesn't work how you expect.
 

LB82

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I don't really understand what you're saying.

It's my understanding that with 1 sidechain L & R are mixed then hit the sidechain, therefore things which appear central hit the sidechain twice. In turbo mode L & R each have their own sidechain & the sidchain that isputting out the highest level is is the one that is fed to both L& R VCA's. Therefore sounds with quite a bit of energy (like bass) get compressed more. To me the effect is that the bass sounds light & the high freq content sounds pushed wide. i.e scooped in the middle. My GSSL is switchable & I literally never use it without the Turbo mode.

Maybe the reason your unit is grabby is because the turbo mode isn't implemented right or you have a wrong component somewhere. As Moamps says your box lacks some basic safety features, showing a lack of understanding by whoever built it. This maybe a clue as to why it doesn't work how you expect.

If I understood correctly I think it's the other way around, with mono sidechain the summed "center"will hit it harder, also usually the bass heavy/high energy elements of the material (kick, bass etc.) are mono and centered.

About the working state of the compressor, it works fine, I have it since years and used it many times, I would have got rid of it somehow if I didn't liked it, I was curious about that sidechain/turbo mod thing to know more about the compressor, so I wrote a thread here to have more info, that's it
 

Rob Flinn

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If I understood correctly I think it's the other way around, with mono sidechain the summed "center"will hit it harder, also usually the bass heavy/high energy elements of the material (kick, bass etc.) are mono and centered.
Yes, exactly what I was saying. the bass hits the sidechain twice with the single sidechain, which means it's compressed more.

You really should sort the Earthing out on your box. You wouldn't be able to sell that box commercially in the EU. It's not up to basic safety standards.
 

amplexus

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Jan 11, 2018
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I have seen pictures of the innards of quite expensive boutique gear that looked worse. What is wrong with diodes as bridge?
Hmm.
Most of those at least have the safety ground connected.

what’s wrong with using diodes hacked in place of a bridge? It’s lazy and sloppy. The pcb has a footprint for a specific part. It’s not even like the part is expensive or hard to find. It’s about as common and costs the same as 4 1n400x diodes. The only reason for doing it is laziness. And if corners are cut in something that small- it’s likely as bad or worse in other places.

Also there are plenty of expensive “boutique” builders who honestly have no business being IN business. There’s no excuse for sloppy, unsafe work in DIY, let alone a commercial product- let ALONE an expensive product. 80% of my income is as a gear tech, so I see dozens of high end products across my bench monthly. If I didn’t want to get my arse sued into oblivion I could write novels about the kind of bullshit found in the highest of high end name brand gear. Shitty lead dress alone can- in many circuits- cause all sorts of issues. Some of which may not be “audible”, but might be impeding functionality or showing up under only certain circumstances. Leading the user to believe they have a functional piece of gear because it “works” but isn’t performing the way it should. One very popular SSL comp clone I know has a layout issue on the pcb that causes significant IMD when you hit it with low freq. 60hz content. I know this because I was their warranty tech for a hot minute until i realized they had no intention or even understanding of the issue even after I sent reams of test data to them, and was able to reproduce it in multiple units across several production runs. Most people using them don’t notice- until they do.

Sorry, but saying “well some expensive gear looks worse” isn’t any kind of valid reason.
 

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