GSSL SuperSC board

[ptron]

Hello ppl,

I'm building a Gssl with SSC. I want to use a switch or similar EAO. If I use a switch with LED 12v, I just have to connect the bypass switch to the SSC board (In led iand In Sw)? I need DPDT or SPST?

Thanks

Hugo

im using this ones Mouser #: 633-HB16CKW01-5F-JB
Mfr. #: HB16CKW01-5F-JB
Manufacturer: NKK Switches
Desc.: Pushbutton Switches SPDT ON-ON ROUND GRN LED/CLR-WHT CAP
RoHS: RoHS Compliant By Exemption

 

[Holiveira]

Thanks

 

[audiophreak]

Hi All,
      I posted this in the GSSL Help thread - but thought it was better posted here  :

  Hi All,
        Haven t been in this thread in awhile.  getting back to my first GSSL , wanted to do the permanent Turbo with dual SSC's , I know there are a few graphics around showing this hook up arrangement , but am still stumped on the Dp8T  dual deck switch.  I know why its needed , but for me its actually getting the right switch , I can only seem to find 10 or 12 position switch, and so far not knowing how to get it to stop at the 8th position ( or to just deal with it ) has given me an Idea  ( watch out .. the smoke is rising )  ;D 

    can the EXT (s/c )  and the OFF positions from the SSC be hooked up to a DP3T  ON-OFF-ON switch ?    - and then use a 2 X 6 Lorlin for the remaining ? 

  and if so .... how would that be wired ?

  Thanks,
            Chip

 

[marcfrom]

Hi guys,

Does anyone have the schematics ?

I want to add a 300Hz frequency filtering, what is the values of the caps and resistors ?

Thanks

 

[Harpo]

Does anyone have the schematics ?

I want to add a 300Hz frequency filtering, what is the values of the caps and resistors ?

So you have the schematic, but its in 3D, drawn with traces and real world parts.
For your 300Hz HPF, series cap value connected to the 12K shunt resistor for this 1st order rolloff is 44.2nF. A standard value 47nF would set this -3dB point to 282Hz.

 

[marcfrom]

Thanks Harpo,

I found a solution, I put 2X 22nF caps in parallel, it's working perfectly for this low cut at 300Hz.

Marc

 

[ptron]

Hi All,
      I posted this in the GSSL Help thread - but thought it was better posted here  :

  Hi All,
        Haven t been in this thread in awhile.  getting back to my first GSSL , wanted to do the permanent Turbo with dual SSC's , I know there are a few graphics around showing this hook up arrangement , but am still stumped on the Dp8T  dual deck switch.  I know why its needed , but for me its actually getting the right switch , I can only seem to find 10 or 12 position switch, and so far not knowing how to get it to stop at the 8th position ( or to just deal with it ) has given me an Idea  ( watch out .. the smoke is rising )  ;D 

    can the EXT (s/c )  and the OFF positions from the SSC be hooked up to a DP3T  ON-OFF-ON switch ?    - and then use a 2 X 6 Lorlin for the remaining ? 

  and if so .... how would that be wired ?

  Thanks,
            Chip

i use this ones since is only sidechain filters no worry is not lorlin IMHO

Mouser N.º: 105-SR2611F-18-18NS
Fabricante N.º: SR2611F-0108-18F5B-D8-N
Fabricante: Alpha (Taiwan)
Desc.: Interruptores rotativos 1 POLE 8 POS D SHAFT
RoHS: En conformidad con la RoHS

 

[Sorr]

Hi All,

I have a GSSL with Turbo and two SSC's to fix for a someone who couldnt build it and gave it to someone else who did but gave it back not working.
Not being very familiar with it I spent hours searching dozens of sometimes confusing threads to get the basic concepts.
After fixing wiring errors, bad joints and a blown VCA I have now got the main board to compress.

Now have installed Turbo and two SSC PCB's.
One S/C split from main pcb to one SCC L input and its return to S/C return main PCB.
Second S/C split from main pcb to second SSC, its O/P (Ret) to Turbo PCB via its switch.
From switch back to main PCB S/C return.

It is working but the threshold sensitivity is reduced as mentioned in a previous post.
I have changed the input resistors (SSC L inputs) to 10k but still have the problem.
Looking closer I have realized that there are no connections from Pot A or Pot B on either SSC.
PCB's
Looking at a drawing I can't see properly where these wires go to on the front panel control board?
I assume only one SSC PCB is connected via pot A & pot B?
Thanks for your help.

 

[Harpo]

It is working but the threshold sensitivity is reduced as mentioned in a previous post.
I have changed the input resistors (SSC L inputs) to 10k but still have the problem.
Looking closer I have realized that there are no connections from Pot A or Pot B on either SSC.
PCB's
Looking at a drawing I can't see properly where these wires go to on the front panel control board?
I assume only one SSC PCB is connected via pot A & pot B?

Pot A/B connections (only one SCF-pcb connection needed) don't neccessarily go to the front panel control pcb at all. The relay connects the wiper of makeup pot with 'E' on the main pcb connection to control pcb. Make sure, the wire link next to the 750K on control pcb is not fitted, else this connection will override the relay function to steady connected (makeup always working, no matter if bypassed or compressing).

 

[Sorr]

Thanks Harpo.

There is no link next to 750k connected. The bypass switch is wired in there.
There is a jumper between the Com and On just below the relay on both SCC boards.
The PCB is the same one Barcelyon has on his site.

That leaves the question why the threshold control has reduced sensitivity?
A schematic of that PCB would be a great help!

 

[Harpo]

There is no link next to 750k connected. The bypass switch is wired in there.
There is a jumper between the Com and On just below the relay on both SCC boards.

So the relais are not connected, only clicking, moving air and drawing unneccessary power.
Either keep only one and connect this relay as described on barclaycons site if you want a status control as well, showing up when the relay gets engaged, or get both relays out when keeping your DPDT switch arrangement as shown on the GSSL schematic.

That leaves the question why the threshold control has reduced sensitivity?

Double check (or increase) the resistor value of the 12K feedback resistor located between the headline 'SUPER SIDECHAIN' and above the left side opamp.

 

[Sorr]

Also links installed on "To  InSW  Ret"

I think I will remove the relays

Sent some tone in, getting half the input signal on SSC output.
Will check 12k feedback resistors.
Thanks.

 

[Sorr]

The feedback resistors are 12k.
Have increased them to 21K5 get more gain and now SSC is working.
Still seems strange that these SCC boards need this mod when it seems others did not?

 

[Harpo]

SCF should be unity gain in the pass band. Some other spots to get to your response issues ...
You 'changed the input resistors (SSC L inputs) to 10k' but fed signal to SCF R input (Rin still 20K) instead.
(no need to change value of input resistors. Just parallel both inputs per SCF board, IE 20K||20K=10K).
Feedback resistor of summing stage 5K6 instead of 10K.
12K resistor connecting to 'SW POLE' 22K instead (BTW increasing the -3dB cutoff frequency of the 1st.order HPFs by an octave).
Testing at a lower frequency, a selected HPF is responsing to.

 

[Sorr]

The i/p R's had already been changed to 10k. So going in one one leg.
"Feedback resistor of summing stage 5K6 instead of 10K."
Why do you recommend reducing this value and which op amp is the summing amp?

 

[Harpo]

Sorr, maybe its a language thing, but I did not recommed to reduce the 10K to 5K6. I was only pointing out some spots where things might have gone wrong to make your 21K5 neccessary for comming back to normal threshold sensivity.

 

[Siegfried Meier]

Just built up one of these into a regular GSSL and am trying to adjust TL and TM trimpots.  The manual says to get 8dB of GR with a 1k tone, and then switch to both TL and TM and get 8dB as well.  No matter what I do, I cannot get 8dB of GR in either of those positions.  I can get max 4dB with the trimpot in it's highest excursion.  All frequency positions as well as the external setting work perfectly. 

What am I doing wrong here?

Thanks!
Sig

 

[Harpo]

Just built up one of these into a regular GSSL and am trying to adjust TL and TM trimpots.  The manual says to get 8dB of GR with a 1k tone, and then switch to both TL and TM and get 8dB as well.  No matter what I do, I cannot get 8dB of GR in either of those positions.  I can get max 4dB with the trimpot in it's highest excursion.  All frequency positions as well as the external setting work perfectly.

... or any other dB of GR.
At 1kHz you want unity gain in both TL and TM settings.
Feed your GSSL with a 1kHz signal, maybe 1V. Adjust trimmers, that both TL and TM signals at the corresponding lorlin switch settings (or IC2-pins 1 and 7, whatever is easier to probe) read the same 1V. This will be with the trimmers in their about center position.
Don't get there? Double check resistor and cap values for these filter stages.

 

[Siegfried Meier]

Doh!!!!!  Forgot to remove 47k resistors on the GSSL board...

:'(

All working great now, thanks so much!
Sig

 

[mrcase]

hey!

How do you calibrate the TL /TM settings if you are using 2 SSC with switchable Turbo? Since my meter shows only "mono" gainreduction how am I supposed to do this properly? Both boards are always in the circuit (wired like explained in the Expat manual)

thanks!
Martin