GSSL HELP THREAD!!!

[Harpo]

(1 pushbutton will be powered by the ControlBoard). Both buttons are blue LED, meter is white LED.

You already added the turbo board to the low power +/-12VDC supply rails on GSSL board, so you better would lighten the load by not connecting the pushbutton LED from control board but from the other SCF board (or the else not needed optional 7812 vreg on GSSL board) instead.

 

[MiamiBoy]

Gotcha, that was the answer I was looking for. I changed the routing now to the RIGHT ssc.
I don't need a relay for that, no? I only have a relay on the LEFT ssc.

 

[nextB]

Mine is built with vintage gold cans. I'm wondering if I can reduce noise and hum further. Sensible options?

 

[separateness]

As far as implementation in this circuit goes, is the 2159 completely equivalent to the 2155? I have been trying desperately to find what resistors to put where and minimize de/resoldering but there seems to be little to no direct information on implementing the 2159. It is not mentioned on the Matt Fischer DIY audio table (and the information on the 2155 is scant anyway). My best guess, based on the datasheet is:
Pin 5: 5.1kΩ to -15V and omit the resistor which connects to the previous stage
Pin 4: 51Ω to ground and 300kΩ (or 390kΩ or 470kΩ) to the trim pot and jumper the other series resistor to the trim pot.

I have used the search function many, many times over the last week both in this forum and on the internet broadly and would prefer not to ask anything at all. If some one would edify me just this once on this issue, I promise never to ask anything in this thread again.

 

[Dylan W]

Does anyone have schematics or information for the SSL 9K bus compressor?

I like the sound better than the 4K/Alan Smart sound - it's less colored, which is better for the music I work on.

It apparently uses VCAs in a balanced configuration. Thinking about building a GSSL with those mods, if anyone has a schematic it would be appreciated.

 

[monsieur yumels]

Hello dear fellow builders,

I (hopefully) almost finished building a basic SSL Mixbus Compressor Clone based on Gyraf Schematics. I used iluminated pushbutton 2pole switches for bypass and power. Hence, I have to link the makeup gain pads on the pcb for the makeup gain poti´s middle pin voltage to affect the Tl072 non inverting input on pin 6.

I wonder if there is any solution for bypassing sidechain, makeup gain and LED without having to change the 2pole switch by a 3pole lorlin type or similar as indicated in the Gyraf schematics.

Any idea?

Thank you!

 

[MiamiBoy]

I had the same issue.
I was forced to expand mine with two SuperSideChain boards.
That’s the only reason I’ve added the SSC’s, because they have relays.

But you can also add a single relay board instead, it’s much more simple than two SSC boards (and more cost efficient).
But the SSC is better documented than a diy relay board (but more pricy). So, you have to choose between two evils.

Good luck

 

[MiamiBoy]

I wonder if there is any solution for bypassing sidechain, makeup gain and LED without having to change the 2pole switch by a 3pole lorlin type or similar as indicated in the Gyraf schematics.

Any idea?

Check this out : Bypass relay PCB: available

And maybe SIXTYNINER can guide you

Or you can go ahead and add 1 SSC board, if you’re not gonna have the Turbo installed. If so, then you need two SSC’s boards.

 

[spoontex]

For me the most difficult part of any build, are always the GND connections. It's very confusing for me. So, I upload a photo of my actual build. I use TRS instead XLR, for instance I thought that the pin 1 of any XLR ( GND on TRS ) need to go always to chassis and never to the 0V circuit. But If I do this way I have a hum, so I connected 0V to the input GND and hum has gone. But, anybody can tell If a made some mistake?

Thanks.

 

[MiamiBoy]

Chassis is automatically connected to the 0V, in the gSSL schematic, so you’re right.

Pin 1 (Sleeve) goes to chassis ground. Chassis ground is connected to 0V.

Try testing connectivity with a DMM between a 0V point on pcb and chassis. You should get a ‘beep’

 

[spoontex]

Chassis is automatically connected to the 0V, in the gSSL schematic, so you’re right.

Pin 1 (Sleeve) goes to chassis ground. Chassis ground is connected to 0V.

Try testing connectivity with a DMM between a 0V point on pcb and chassis. You should get a ‘beep’

Yes, I have a beep.

Thanks!

 

[monsieur yumels]

Check this out : Bypass relay PCB: available

And maybe SIXTYNINER can guide you

Or you can go ahead and add 1 SSC board, if you’re not gonna have the Turbo installed. If so, then you need two SSC’s boards.

Hello MiamiBoy!
Thanks for your answers!
.What is the purpose of the bypass pcb board? I read a bit through the post but could not understand the purpose of it.
Is it to bypass with front switch after input XLRs?

Also, am using the DAPB400 british illuminated push-witch from donaudio. So LED is integrated in it. I don´t know if this was clear from my previous post.



Thank you!

 

[MiamiBoy]

Hello MiamiBoy!
Thanks for your answers!
.What is the purpose of the bypass pcb board? I read a bit through the post but could not understand the purpose of it.
Is it to bypass with front switch after input XLRs?

Am actually not the right person to ask about what that add-on pcb’s purpose is.
Hopefully someone else can shed a bit light on this subject.

All I know is that it has relays and it has connections for LED and Bypass Switch, meaning you’ll free up half the pins on the back of your pushbuttons, because you’ll wire the positive&negative from button (LED), directly to the pcb board instead of wiring it to the button poles. It’s a simpler version than adding two SSC. You can also use it if you’re adding Turbo and a single SSC.
This is just one of the versions that’s out there.


I did it the easy way and ordered 2 SSC’s from PCB-Grinder and components from Mouser.

I have the “Turbo & Sidechain” front panel with same push buttons from Don Audio as yours.

This is how I wired everything:
https://groupdiy.com/threads/gssl-turbo-two-ssc-super-sidechain.83820/post-1093438

 

[knariman]

Yea, I guess most people didn't write down how they did things, haha..
which is very normal, but I was afraid of that!

EDIT: I solved it. The rotaries are now soldered correctly ! Thanks everyone

Hey MiamiBoy,

Wanted to know how you figured out how to orient your rotaries? I’ve snapped mine in but haven’t soldered yet because im not sure. I lined up A to A.

 

[MiamiBoy]

Wanted to know how you figured out how to orient your rotaries? I’ve snapped mine in but haven’t soldered yet because im not sure. I lined up A to A.

Well, I just followed the pics from the schematic. The 3 middle switches are marked “1” and “2” in the circle ️. Just line up the numbers rather than the letters.

The “Threshold” and “Makeup” are wired opposite from each other (just look at the picture). You’ll notice right away if you wired those two wrong or not, once your unit is up and running
Makeup goes louder when turning clockwise.
Threshold compresses more when going anti clockwise and no compression when going full clockwise.

 

[knariman]

Alrightt, all boards soldered and ready to go into the chassis one by one! I did have a question, did any of you with a Turbo + SSC build make use of the external input? I'm just curious to know how you'd go about it.

What kind of jack would you use, balanced or unbalanced? I'd assume from one of Jacob's previous vanilla GSSL posts that just a mono unbalanced TS input would work. Is this still the case when doing a Turbo + SSC build?

Secondly, where would I wire jack into the system. I'd assume on the SSC boards now, and not the main board? From what I can presume, if using a single mono external sidechain, id take parallel copies from the TS jack (+ve) to the Ext In on the SSC boards, and provide the return from the 0v/sleeve on the SSC board to the TS jack (-ve). Would be grateful if anyone could provide some detail on this too!

Thanks for all your help guys!

 

[knariman]

Well, I just followed the pics from the schematic. The 3 middle switches are marked “1” and “2” in the circle ️. Just line up the numbers rather than the letters.

The “Threshold” and “Makeup” are wired opposite from each other (just look at the picture). You’ll notice right away if you wired those two wrong or not, once your unit is up and running
Makeup goes louder when turning clockwise.
Threshold compresses more when going anti clockwise and no compression when going full clockwise.

Perfect, got it. Thanks again for all your work and help Miami Boy!

 

[knariman]

So I needed some help. As mentioned above, i'll be using just a single mono jack for external sidechain signal, which will be activated by hooking it up to the rotary switch.

I just wanted some clarity on whether I would be able to connect an Ext Sidechain 1/4" TS jack like so, or whether i'd get a level drop on the sidechain signal due to the parallel split from the jack? If so, how best should I tackle that? Always appreciate the help - from a newbie

View attachment Ext-Sidechain.jpg

 

[knariman]

Anyone? I figure if I parallel split the mono input jack as specified above, the halving of power of each parallel signal should work well feeding the two sidechains correctly. If anyone has knowledge on this, I would be very grateful !

 

[Harpo]

So I needed some help. As mentioned above, i'll be using just a single mono jack for external sidechain signal, which will be activated by hooking it up to the rotary switch.

I just wanted some clarity on whether I would be able to connect an Ext Sidechain 1/4" TS jack like so, or whether i'd get a level drop on the sidechain signal due to the parallel split from the jack? If so, how best should I tackle that? Always appreciate the help - from a newbie

View attachment 112230

Using an isolated (not conducting to your case) TS jack will prevent a possible ground loop.
Your "hooking it up to the rotary switch" is missing in your drawing, so signal from bottom left EXT can make it to SW-POLE.
You only need to connect to one EXT-in. This external signal will always be the higher of two, generating the control voltage for both audio-VCAs.