GSSL w/ stereo SC (Turbo), mono SC/SSC, Crush'n'Blend (pics)

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Holger

Well-known member
GDIY Supporter
Joined
Jun 11, 2006
Messages
893
Location
Hamburg, Germany
This weeks DIY (am I really that mad?) is a 'slightly' modified GSSL.
It has the stereo side chain mode AKA Turbo board (thanks again to Keith et.al.), but it also has a mono side chain mode with the SuperSideChainBoard including the TH***T function and the Crush'n'Blend board conceived/produced by Lukas.
front4.jpg


It's custom painted in a kind of battle ship grey/blue. Frontpanel is done by FPD/Schaeffer, the meter is a Sifam 14 PPM.

front3.jpg


The side chain mode switching is done via two relays. In the mono mode, the two "right side 47k" points go ( without the resistors) to the SSC board. Switched, the one "right point 47k" goes to the turbo board, the other goes to the boards own SC, this time surely with 47k.
The other relay just lifts off two turbo board connections in the mono mode.

relays.jpg


Maybe I will learn to make a more professional looking wiring one day.

guts2.jpg


All in all a wonderful, versatile compressor. Maybe I will modify my other GSSLs sooner or later.
 
looks great!  how's the crush 'n blend working?  did you use keith's original schematic?  i need to read up on this.. 
 
yes Holger

Very nice FP i like your blue face and the elephant knobs.
You can add a second SSC to the turbo that give you a full OXFORD Mods.

The c'n'b is very very very great addon 
good job pure DIY


how's the crush 'n blend working?  did you use keith's original schematic?

The c'n'b for GSSL is the LUKAS (livingnote) design (unbal).
read this for more info
http://www.groupdiy.com/index.php?topic=31246.0


 
Wow I really like the colorful wiring. Funny how colorful and jovial it is inside, and how outside it's total military snazz...

"Radar, copy, turn left heading 157, over." ---ccchhhhhbzzzz BOOM (red lights flash and someone starts frantically turning the knobs and yelling stuff). "Sir, we have lost sidechain control, sir! Permission to bypass?" - "Negative!" - "Sir, the feedback will reach critical levels if we don't bypass now, sir" - "I said wait. If we bypass now, we might not have a chance to regain signal integrity before the song is over" - "But that's risking the entire production, Sir" - "I know, and now sit tight, this is gonna be one hell of a ride"

;)
 
i like these colorful work, its an inspiration to me. my diys will have those color wires too but not as much as yours. just 3 or 4 color types... actually a bummer closing the case.
i thought flexing a hole in the top and putting plexiglas in to see the nice work.

bye
 
creal said:
You can add a second SSC to the turbo that give you a full OXFORD Mods.

That's what I didn't want to do. The idea was here to build a true two mode compressor. As Keith mentioned a couple of times, there is no need for a side chain in the stereoSC/turbo mode. AFAIR the original SSL Compressor never had the side chain functionality.

diyfanatic said:
ahahaha  ;D

you make my day LUKAS lol

Same here, thanks Lukas  ;D

@hotbaby, since I don't like my style of wiring I'm happy once the case is closed and stuffed into my rack... ;)
 
Hi Holger!
I must I am a big fan of your metal work!!
especially those Altec look like racks.

forgive by advance, I'll take one or two ideas of yours for my D-AOC!!  8)

just a little question.
I've seen you've done your front panel by FPE and the paint by a local shop.
but how have you done the lettering? lazertran?

or did you made the painting first and sent it to FPE and they made the holes and the lettering?

Cedric.
 
diyfanatic said:
Hi Holger!
I must I am a big fan of your metal work!!
especially those Altec look like racks.

forgive by advance, I'll take one or two ideas of yours for my D-AOC!!  8)

just a little question.
I've seen you've done your front panel by FPE and the paint by a local shop.
but how have you done the lettering? lazertran?

or did you made the painting first and sent it to FPE and they made the holes and the lettering?

Cedric.

Cedric, thanks for liking my design style.
So, I purchased the cases first, got the panels painted, then sending the painted panels to Schaeffer.
But: everytime I start a new batch it turns out that, depending on the painting (glossy finish etc.), the results are a little bit different.
When you look at my Pico (the first green one)
http://www.picocompressorforum.com/forum/php/viewtopic.php?f=7&t=58&start=30
you can see that, as an example,  the R in the word 'THRESHOLD' isn't perfect since I used the 0.4mm engraving tool here at a specific typo height.
On the new grey line I used a very fine engraving tool for my 'logo' (not seen in the pictures), filled with white paint. This results in a 'silver' look which wasn't intended. So every custom painted panel has its own problems when it comes to engraving.
 
Wow Holger thats so nice!!!!!!!!!!!! :eek: I am planning to do the same thing minus crush n blend. I am trying to understand how to create the switching though can you lend some advice. I like the Idea of  it being a 2 mode compressor.

Thanks
 
loopermc5 said:
I am trying to understand how to create the switching though can you lend some advice.
The point where the stereo signal is summed to mono (the two 47k resistors before the sidechain VCA) is the important area. Lift the resistors and put the signals from the stereo side to a relay. Determine which mode is the switched one (I choose the turbo  mode).

SC%20switch.jpg


Mono SC:
Assumed the mono mode is the unswitched (relay is not active) mode. The two non-switched outputs of the relay are going to the SSCs two inputs. The SSC output (which is mono) goes back to one hole of the main PCB 47k mono summing point.
Stereo SC:
One switched (turbo mode) relay output goes via a 47k resistor to the turbo board, the other one goes via a 47k resistor to the other empty hole of the main PCB 47k mono summing point.
Additionally I've used a second relay for connecting the turbo's +/- V and a third relay for connecting the S/C & S/C.C.V point.
I hope that explains it a little bit.
 
Oh I like the turn with switching the power of the stuff on and off as the circuit is engaged and disengaged - even if it isn't necessary, it's a cool principle - and what I particularly care for is that the turbo gets detatched electrically when powered down, that makes some serious sense - I remember us once losing signal because the low-impedance output of the un-hooked opamp sucked the life out of the signal when it was off and dangling.

One thought - in this configuration - and with a relay-switched SSC - it would be possible to stick the turbo switch in as a position of the SSC switch - so you just have position 9 "Turbo" and that switches power to your little relay nest up there. That way you have one all-in-one-uber-sidechain-switch (admittedly for 10€ extra in relays but what the heck ;)

I just noticed that because on mine I have a little "dual Steffen" with relays that I can run both signals through separately  and still be able to use my SC filter in full turbo mode. Might be cool to make a little SSC that can do that.

But great. Sooner or later we'll need to make a little PDF with all the possible crazy mods and upgrades for the SSL in here...
 

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