GSSL add-on help thread

[MiamiBoy]

Yea, if you’re planning on installing the Turbo to your unit that has a SSC, then you’ll need to add another SSC board.

If your unit doesn’t have a SSC, and you wanna add the Turbo, then you don’t need to do anything more (depends how many buttons/switches you want on the front -that can change your configuration regarding your total mod).

I think, if you add a SSC board, then it will solve the whole Turbo situation and a Turbo won’t be necessary/needed. I’m not a 100% sure though!

 

[Script]

Various implementations. Depends on what you want / need and how much work you are willing to put into it.

(1) GSSL board only (no Turbo, no SSC) -- this is called "Vanilla GSSL" (there's that long thread).

(2) GSSL & 1xSSC (but no turbo) -- SC is mono, the SSC board alleviates mono buildup in the sidechain.

(3) GSSL & Turbo (but no SSC board) -- modes are "Aarhus" (audio mono'ed into 1x SC detector ) and "Oxford" (stereo into 2x detectors).

(4) GSSL & Turbo & 2x SSC -- switchable between the two modes, with both modes offering side chain filtering.

Variant (2) introduces SC filtering to 'fix' the mono buildup in the SC (+6dB) of the Vanilla, plus it gives additional features such as a side chain EXT IN and tilt-shift filtering (some call it 'thrust').

Variant (3) fixes the mono buildup in the SC (+6dB) of the Vanilla by adding a second detector, but it does without any filtering option. The argument is that the SSC filter board was introduced only as a 'fix'. Also it does without the 'thrust' thing.

Variant (4) has the two modes plus filtering in both modes. To do this requires two SSC boards and careful consideration of how it all hooks up (( not plug-and-play -- headache allert ! )).

With only one SSC board, there should be another option:

(5) GSSL & Turbo & 1x SSC only -- switchable between Aarhus mode with SSC filtering VERSUS Oxford mode without any filtering. Different hookup.

Depending on how many filter options you really want or need, there should be yet another option:

(6) GSSL & Turbo only -- later GSSL board revisions do the SC filtering not by adding a SSC board, but by changing only one cap sitting before the rectifier in the side chain. Should be possible to do that on both the GSSL board and the Turbo board, I'd think.

____
Personally, I like the filtering options also in turbo mode (hence 2xSSC boards), but partially so because I ditched the EXT IN and instead added yet an extra bunch of filtering options including active filters. Interestingly though, after all the headaches, I also came to appreciate the plain Vanilla & SSC version more with its simple filtering of the mono'ed sidechain. Mono'ing the SC might sound like a fault, but it's also kind of a feature as it 'enhances' stereo so to speak -- cos can't compress what it can't see).

If I were to build another GSSL+, I'd probably go for variant (6) and put filters on a veroboard. Or I'd go variant (7), a GSSL & Turbo, and implement 2 x EXT SEND and RETURN to hook up an external stereo equaliser.

 

[MiamiBoy]

I went with number 4 and added 2 push buttons. If you wanna follow my path: https://groupdiy.com/threads/gssl-help-thread.47/post-1102440

Add-on “SSC & Turbo” mod:
https://groupdiy.com/threads/gssl-turbo-two-ssc-super-sidechain.83820/post-1093438

Whatever you end up choosing, it is recommended, by the community, to first build the “vanilla” GSSL, to make sure you have a working “stock” unit before heading towards different variants of mods.

 

[Mugge]

Hi all,

I've been working on a small GSSL add-on - a tilt filter for the sidechain.

Read more here: https://groupdiy.com/threads/gssl-add-on-sc-filter-tilt.87408/

/Marcus G. K.

 

[antiehdas]

oh, I just posted this in the main help group, gut now I found this group.

Hello Everyone ! just finished my Gssl with Super Sidechain mod. and well, I get no signal at all. I know, I should have build the vanilla version first, check and then put the side chain mod in ... me stupid...now I have to pay for it.... I will do this tmrw. But before I go to sleep I was thinking putting it here. maybe someone finds an error immediately, or maybe I get some tipps on how to start troubleshooting. Will reverse to vanilla version asap to see if the error is in the mod. I only checked for 15v + and - , nothing more, this was fine. send audio in but got nothing out, with compressor engaged or bypassed. leds are on, so that's a good start

 

[LNS]

oh, I just posted this in the main help group, gut now I found this group.

Hello Everyone ! just finished my Gssl with Super Sidechain mod. and well, I get no signal at all. I know, I should have build the vanilla version first, check and then put the side chain mod in ... me stupid...now I have to pay for it.... I will do this tmrw. But before I go to sleep I was thinking putting it here. maybe someone finds an error immediately, or maybe I get some tipps on how to start troubleshooting. Will reverse to vanilla version asap to see if the error is in the mod. I only checked for 15v + and - , nothing more, this was fine. send audio in but got nothing out, with compressor engaged or bypassed. leds are on, so that's a good start

Can't see anything obvious, revert to vanilla and it will be much easier to troubleshoot.

 

[Harpo]

oh, I just posted this in the main help group, gut now I found this group.

Hello Everyone ! just finished my Gssl with Super Sidechain mod. and well, I get no signal at all. I know, I should have build the vanilla version first, check and then put the side chain mod in ... me stupid...now I have to pay for it.... I will do this tmrw. But before I go to sleep I was thinking putting it here. maybe someone finds an error immediately, or maybe I get some tipps on how to start troubleshooting. Will reverse to vanilla version asap to see if the error is in the mod. I only checked for 15v + and - , nothing more, this was fine. send audio in but got nothing out, with compressor engaged or bypassed. leds are on, so that's a good start

missing jumper at the HPF-position on main pcb.

 

[monsieur yumels]

Hello!

I have been looking but did not see any clear answer to following question:

I plan to install one pcb grinder SSC board (like antihedas up there).
In the vanilla state, I have the wiper of makeup poti connected to one pole of the sidechain bypass switch (a DPDT pushbutton) and back to the board, so that makeupgain gets killed when sidechain bypassed. The other double throw pole is connected to com/on/off.



As I understnd from PCB grinder documentation, should i connect the DPDT now to the "com/off/on" and "IN SW" of the SSC board?


What should I do with the two solder points and the com/off/on on the control board that i have now wired with dpdt switch? If i solder a link, make up gain will be constantly engaged i assume, and i do not want that.
And, what are connections Pot A und Pot B meant for?

Thanks for your help,

José Manuel

 

[Harpo]

Hello!

I have been looking but did not see any clear answer to following question:

I plan to install one pcb grinder SSC board (like antihedas up there).
In the vanilla state, I have the wiper of makeup poti connected to one pole of the sidechain bypass switch (a DPDT pushbutton) and back to the board, so that makeupgain gets killed when sidechain bypassed. The other double throw pole is connected to com/on/off.

View attachment 130087

As I understnd from PCB grinder documentation, should i connect the DPDT now to the "com/off/on" and "IN SW" of the SSC board?
View attachment 130091View attachment 130090

What should I do with the two solder points and the com/off/on on the control board that i have now wired with dpdt switch? If i solder a link, make up gain will be constantly engaged i assume, and i do not want that.
And, what are connections Pot A und Pot B meant for?

Thanks for your help,

José Manuel

Com/Off/ON correspond to C7/8 and PotA/B correspond to A1/2 on the 2*6 lorlin switch on control PCB. You need to connect these to the sc filterboard. The connection 'In when closed' operates the relais on the sc filterboard in order to open (A1) or close (A2) the pot-wiper connection and control-voltage (C7) for Off and (C8) for On.

 

[desol]

I'm pretty sure Serpent Audio had a redone board (SB4000) with all the mod's and fixes included! Yay! But they don't appear to offer it any more. Boo!

 

[craigmorris74]

I’ve read where Peterson at DIYRE could consistently hear a difference in using LF351’s in the side chain instead (he used the LF347N in his kits) of the TL074 in the. GSSL.
I’m curious to know what the sonic difference is like, and was wondering if the the LF347N could be swapped for the TL074 with out any other changes?

 

[TJS]

Hi,

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

The GSSL alone works great with no issues.

When I connect the SSC (link below) 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 when the SSC is engaged.

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

In terms of wiring:

I have the com/on/off from the main board connected to the com/on/off on the SSC.
Makeup on and com are connected to pot A and B on the SSC.
I have a Lorlin rotary switch with SW TO going to A, and SW RET going to pin2 (on my panel, and pin2 position compressor is in).
MeterLED and IN LED on the SSC board are not connected to anything.
HPF points on the main board are connected.

I've removed the 47K resistors on the main board and added L/R/RET to the respective ends of where the 47K's were.

I'm using this SSC with a relay here:

https://proaudiogc.com/en/gssl-super-sidechain-filter-with-relais-in-out-pcb

Thanks!

 

[Flundran]

I'm looking for a PCB layout for the Turbo mod. Is it available somewhere? I would like to make (etch) my own PCB.

 

[pridon]

Hi,

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

The GSSL alone works great with no issues.

When I connect the SSC (link below) 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 when the SSC is engaged.

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

In terms of wiring:

I have the com/on/off from the main board connected to the com/on/off on the SSC.
Makeup on and com are connected to pot A and B on the SSC.
I have a Lorlin rotary switch with SW TO going to A, and SW RET going to pin2 (on my panel, and pin2 position compressor is in).
MeterLED and IN LED on the SSC board are not connected to anything.
HPF points on the main board are connected.

I've removed the 47K resistors on the main board and added L/R/RET to the respective ends of where the 47K's were.

I'm using this SSC with a relay here:

https://proaudiogc.com/en/gssl-super-sidechain-filter-with-relais-in-out-pcb

Thanks!

I have the same issue with the same pcb, I looked at the schematic for the pcb and it seems that TM TL and normal filters are not connected and only TM connects to the input, i tried to hard-wire it but i was having erratic behavior, finally i gave up and ordered another supersidechain from pcbgrinder. This was my second SSC pcb, the first one was the classic one from pcb grinder and that was working fine.

 

[macleod69]

Hi,

I had the same problem, the fix has been posted on the site.
On some series, a track has been forgotten!!
If that can help

 

[Tetard]

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 ;-)

 

[H0004]

Hi,

I had the same problem, the fix has been posted on the site.
On some series, a track has been forgotten!!
If that can help

Hi,

There was one other missing trace on the https://proaudiogc.com/en/gssl-super-sidechain-filter-with-relais-in-out-pcb, unfortunately. See this pdf for details: https://proaudiogc.com/en/index.php?controller=attachment&id_attachment=57

With both fixes, the board seems to work well!


EDIT
I was wrong. Unfortunately, it seems that more issues remain with this PCB. Based on the only schematic for the SSC PCB I could find, the position of the 12k resistor around the return path is wrong too, and the return path should connect to pin 1, not pin 2.

 

[pridon]

Hi,

There was one other missing trace on the https://proaudiogc.com/en/gssl-super-sidechain-filter-with-relais-in-out-pcb, unfortunately. See this pdf for details: https://proaudiogc.com/en/index.php?controller=attachment&id_attachment=57

With both fixes, the board seems to work well!


EDIT
I was wrong. Unfortunately, it seems that more issues remain with this PCB. Based on the only schematic for the SSC PCB I could find, the position of the 12k resistor around the return path is wrong too, and the return path should connect to pin 1, not pin 2.

Yeah I don't know I also tried but finaly I ordered a pcb from pcbgrinder, populated it replaced it and all works fine now, i messaged proaudiogc about this but never got a reply so I would suggest to avoid buying the super side-chain pcb from proaudiogc unless it's redesigned.