Crush Implant and GSSL porn ;)

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livingnote

Well-known member
Joined
Aug 12, 2007
Messages
1,048
Location
Berlin, Berlin
As if the poor GSSL board hasn't had enough abuse already...


Tough Chicken. Surgery time!

surgeons.jpg


(I wouldn't trust these guys either ;) That's me on the left)

Here is the battle plan:

schematicincision.jpg


After a bit of thought, I decided it would be best to get in there right before the VCA
input cap, and to go out after the first opamp in the output section.

The idea is to tap off the input, and "break in" to the output. Now there were
some differences on the rev9 board from the rev7 schemo, so we'll be lifting
caps on the output in place of the 100R.

componentbreak.jpg


These are the legs we have to lift. It'll be the + side of the input caps, and the
output caps as well as the 10K resistor that goes to the inverting opamp.

In practise, this looks like this:

wiresolder.jpg


Note that I screwed up a little here, I forgot to lift the output 10K's. Also, I didn't solder
the wire to the input caps' legs, which I corrected (it was 4AM) by soldering a separate wire to the
Cap leg itself and then twisting them together  ::)

Now for the actual connections (blue is left, red is right):

1. On the input caps, solder the lifted leg to the wire and to the hole where it came
from, retaining the original continuity. Alternatively, you can just solder in a wire on the
bottom of the PCB. All we want to do is sniff the signal, while keeping the artery to the VCA intact.

2. Solder the output caps' freed legs as well as the freed 10K leg all together and attach
a separate wire to them.

Now we have our signal tapping point as well as our little "window" on the output to
break into.

Before we proceed, it is a good idea to twist together the output wires respectively
and see if the compressor still works as before. That way, we'll know if we screwed
up here and it will save a lot of headache.

Now for the actual implant:

It's a good idea to power up the CnB board by itself first before you stick it into your
SSL. That way, if you have anything backwards, you'll just screw up a little part of
things.

Additionally, find a good spot for the CnB board well away from the tranny to make
sure it does not pick up hum. Being unbalanced, it's quite the antenna and so special care
must be taken to ensure it stays quiet. (Yah, screwed that one up myself).

On the Crush board, we have LD and RD (Left Dry and Right Dry), these guys get hooked
up to the wires on the input caps.

Next, we have LW and RW on the CnB input, these go where the wire comes out of the
PCB
at the output.

Now for the CnB output: Hook this up to the soldered-together-caps-n-resistor legs.

Then, carefully bring your patient back from his anesthesia and if all went well, you have
yourself a blend control.

Side Note: If you want to adapt the opamps' positive terminals to the same R value as
on the SSL itself, well, the Rev2 CnB sticks these straight to ground (which is too bad,
a change I will make in Rev3) and so you have to mod the chip itself.

Carefully bend up legs 3 and 5, and to each of these, solder a 22K resistor to the two input
opamps' legs each, and for the output one, grab two 470R ones.

moddedr.jpg


Solder the R's other ends together, and hook that point to ground somewhere.

rtoground.jpg


I can't be sure this really makes a difference, because theoretically opamps have infinite input impedance, but to me it feels as though the construction sounds more "open" with the resistors attached. And then I feel it doesn't again. And then I feel it does.

If anyone has thoughts on this, of course I'd be happy for your input.

This has been an incredible learning experience for me, dotted with a lot of nightmares
when things just wouldn't work. But heck, in the end I built me a working crossfader, and I would like to thank Keef for his original posting that got this all started, as well as Jakob for the SSL that is oh so fun and addictive to tinker with.

Rock on, guys  :D And thank you. Some things you just don't learn in school.
 
Yep, with those exact boards. And what's more...

The panels are in! Yeehaa! And the other three from the sample run are well under
way.

Here it is:

wholething.jpg



meters.jpg



bypass.jpg



attack.jpg
 
Lukas, congratulations !   VERY retro-space-nice-awesome-cool-super !

Good so see such things in these times of PPMTLLS

(Painted Plastic Made To Look Like Steel)

And adding the LEDs in those rings is nice as well,
elegant!
(I guess I want a metal replacement cover for my Beh. V-Amp  ;) )


Cheers!

  Peter
 
holy crap those panels are cool!!! I've been experimenting lately with raised areas on the cnc, hopefully i can accomplish what I've set out to do.

Sorry for the OT, sweet Gssl.
 
Excellent!

-Let me know what your impressions are of using the completed article.

...and also let me know how much I'd have to bribe you to make me a similar front panel!!!

;)

Keith
 
livingnote said:
Yep, with those exact boards. And what's more...

The panels are in! Yeehaa! And the other three from the sample run are well under
way.

Here it is:

wholething.jpg



meters.jpg



bypass.jpg



attack.jpg

Those look so cool!
sweet!
;D
 
Maybe I've been playing too much Need for Speed. You know, tune the Mazda MX-5?

But yeah, I drooled too when it arrived. It's been a long time coming that this finally gets
done, and here boom-there-pop it all was all of a sudden. And I second that metal thing,
something in me feels that DIY has become where the real quality is at, that old, long-lost
pride in what you're building, and the sincere desire to make it good that has vanished
somewhere between the company books and the market. I think we should show that.

Now this whole hum here and wires there just isn't neat and I kinda want to have it
all on one board.

Especially if I want like 5 of these in my studio, they just gotta be better inside.

Maybe do one with white and red LEDs?

Keith, sure we can design a panel. It would be a lot of fun to do something like
that, after all my diploma is in theater makeup and I know my front work ;) I just got
through doing this with Ruiari, Peter and JDB and it was very enjoyable.

Just be ready for a steep price coming from fab, it's a two-step lasering and etching procedure
and even without profit we're still looking at at least 120 bucks one-off cost, more like 150,
with all the setup charge. But we can do it. Just send me a sketch.

Also, it would be a sin to keep this out of the community, if anyone wants this front design
for their SSL of course we can come up with a deal, it includes LED and meter board and
a custom control board. There's also a custom turbo in, which I designed straight off the
ultimate thread, but that's Keef's board idea and he should be the one who gets the + for that.

Also floating around here is that relay-control HPF based on Steffen's schematic, I have found it
to be very handy indeed. The bal sidechain I/O is also a little illustrator thing, just the ssl's I/O,
and the PSU is there obviously to handle the LEDs via a separate ground line, rectifier and filter.

Darn, this has turned out to be quite the integrated thing...but anyway, I'll be mixing orchestra
on it tomorrow, and then some Chansons. That'll be the acid test.

Funny thing is that that cheapo 2.50 radiohm pot really isn't that bad at all. But
mewants to design a VCA one. Bad.

I somehow always get stuck in Oxford mode. Must be my style of music...

Anyway, you all take care, and thanks for your good words and of course for being such a cool
forum  :D

Lukas
 
damn... the new standards for panels have just been set!  :eek:

This REALLY looks great man!

BTW: about the one board design thing, there is another option that might be interresting to implement in the sidechain filter design which i have been posted before somewhere but i can't seem to find again.
What about a LO pass filter as well? In combination with the crush and blend this will sound really cool for sure! So let's say, only from 20 to 200hz is feeding the sidechain and so you will get extreme pumping because it only responds to the low frequencies (kick), actually way to much but if the original signal is mixed in you will get a really nice punchy sound.
I'll use the fabfilter pro-c compressor pluginn (dutch guys and great pluginns btw) to do that and it can make muddy mixes sound really good and punchy. I will make an example of what it can do.

Anyway.. time for a new board with: turbo, HPF, LPF, thrust, crush and blend  :-*
 
Thanks, guys. Hope to see you in Berlin sometime  ;)

Next thing is gonna be a PSU with 2x on board trafo, built specifically for going nuts on LEDs. Just got off elpro  :D
 
anyone else done this so far?
I am going to build it in the next week or so.
Still a bit confused about where to exactly insert it in what way but i will figure it out, the board itself is almost done. :)
 

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