Internal Crush-n-blend Support thread

>>>This is one of the old, discontinued Crush-N-Blend threads<<<

For current CnB information go to:

http://groupdiy.com/index.php?topic=61934.0

To keep some order, here's the official support thread for installing the internal crush-n-blend for you guys. I have taken the liberty of adding the instructions from the other thread as I kinda hijacked it myself with that front panel. Post any questions here.

Also, I have the boards in stock if you can't or don't want to etch, for the EU it's 10€ including postage and for international it's 12€. You have to drill'em yourself, but yeah, microseries...If I sell'em out, I'll just do a pro run next time.

Anyway, here goes:

First off, blueprints! Please be fair.

Schematic

Components

Photopositive 1200 dpi

And BOM:

3 x 5532N and their sockets
4 x 39K
12 x 10K
2 x 91K
1 Pot is standard 2x10K
8 x electrolytics 22µ or more
10 x 100n WIMA
6 x 33p or 20p wima

Optional:
4x 22k
2x 470r

And here the finished build:





Installation procedure:

Here's a good explains-it-all pic by creal:



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.



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:



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: This has worked great across the board without the bias resistors, but if you wanna adapt to the same as in the SSL, here goes:

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.



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



I can't be sure this really makes a difference, 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. Oh well. You can just leave'em out, I guess...

Alright, show's yours. And be sure to post pictures here if you finish one  ;D

I can tell you this is really a cool add on for the gssl!
I have been playing with it in a 'testmode' for some day's now and it really is nice to have a really over the top pumping sound with the original dry signal mixed in.

One note:
I mixed up two caps while building resulting in a 100nf cap where a 22pf cap should be in place  and so a nice low pass filter  ;D
So watch out for the caps as marked below as it took me some hourss to find out i screwed up there..

Thanks for marking it, now I see what's been screwing you...eagle put out the values where it could and that 22u there didn't help either....

Well here's to your lopass filter  So in one thread you were designing that exact one, and at the same time in the other you had that exact problem! Ahh, the irony...


But it really is amazing, isn't it? Once you have it on the SSL, you wonder how you ever worked without it...

you guys have a clip example of what this thing do?
I'm building a GSSL with Turbo, HPF sidechain and what now???
:

Well basically it's just a stereo crossfader and works well at that, but in the SSL application it's a wet/dry control, so you can first compress the heck out of, for example, drums, and then blend it with the uncompressed signal, so Keith called it crush-n-blend.

I don't have a parallel compression example, but I did do a crossfade test with rather contrasting music, that way it's easier to judge the crossfade law:

Bing&Dimmu

It's cheap, and it's good. Produced 3 CDs through it, and it sounds great. Wish there was more stuff like that...

My two favourite chistmas songs!

How did you know? 

Still haven't decided to add CnB to my GSSL, have to finish sometime...

Regards,

Anders

good thread Lukas

i'm ok for buy you 2 board. i live in france.
Do you use paypal?

Cyril

Sure, just send me an email.

just add the BOM

3 x 5532N and their sockets
4 x 39K
12 x 10K
2 x 91K
1 Pot is standard 2x10K
8 x electrolytics 22u
10 x 100n WIMA
6 x 33p or 20p ceramics

Optionnal:
4x 22k
2x 470r

http://www.dagoosemusic.nl/temp/parallellssl2.wav a mono example (mine didn't work on both channels in the beginning because of the screwup i did a first)

Ah great, Thanks for the BOM, added it.

This is a great idea, I'd add it but I don't want to ruin the front panel of my gssl. It would be really cool to make a separate unit as a cnb.... then you can use it with anything you like! cnb pm670? cnb la2a? why not?!

sure you can make this addon external.
Just add a +15/_15 PSU in your external Blend Box, put a switch and a SUB-D connector in rear panel of gssl.

just keep in mind this addon don't work with balanced signal.

 

Ah, that's what Keef's original schematic was for. With yummy SSMs and a scrumptious OPA, it has everything you need for balanced operation, plug it in between any two devices.

That said, sure you can externalize this one too...but I do have a layout for the one by Keith in the original CnB thread somewhere...

you're right the Keith original CnB is very good for external use.
it's one of my futur builds

And I managed to get it working alright too...now there's this second build which I did to balance and debalance with 5532's, that way you can weasel around SSMs and THATs that cost a lot...but [yoda] time he needs, projects he has too many of [/yoda]

Your boards should be on the way btw.

2 good news Mr Lukas
Thx for sharing your knowledge

Yeah knowledge really is useless unless you share it - and it really helps to teach people stuff.

I'm just a beginner myself, but fast learning here. And fun - you remember those old books with like "301 circuits" that you could just flip through and etch & build what you needed? This is like one of those come to life!

hi Lukas

I found the board in my mail box this morning
Nice work, now it's time to drill them
Thank you

Ah great! I was almost getting worried there - I know what it's like when
you're reeeeally excited to build something and then have to wait

Have fun building them!

Cheers,

Lukas