Crack upgrade: 41 Stepped Series Attenuator

[Loggie]

After having finished my Crack (a thread about that is stil to come)  I decided to upgrade the standard pot with a 41 stepped series attenuator.

I stumbled on the "41 stepper" after Googling for a stepped attenuator and was initially going for a 23 stepped one.
However the "41" caught my attention 
Also more steps would give me a better control.

This attenuator is made by (or made for) Acoustic Dimension in The Netherlands.
It comes in a few variations:
http://www.acoustic-dimension.com/attenuators/attenuators-main.htm

As shown on the pictures below you can see that the resistance is achieved by using 2x41 SMD resistors.

Peter the owner of Acoustic Dimension is a pleasure doing business with.

At first I was afraid it might not fit but after making the original hole slightly bigger it fitted (very tight fit.....see pictures).
The attenuator works like a charm and sounds great.
I measured both the original pot and the 41 stepped one......the original had a 1% inbalance between channels, the 41 stepper none.

Now I only hope that the Speedball upgrade I ordered will still fit  ;D

Here are some pictures:

Update: Added 2 pictures (from the internet)  that show the inside, also visible the 2x41 SMD resistors.
Update2: Removed the casing from the attenuator and made some photo's to show the inside and working.

 

[borism]

Arno, that's a very nice build. Have you thought about the speedball upgrade and how it might fit with the stepped attenuator? You might have to improvise.

Boris

 

[Loggie]

Hi Boris,

I totally forgot that I needed to have some room for the Speedball upgrade .....however I think its possible to move one of the PCB's around a bit to make it all fit.
Its been 4 weeks or so since I ordered the Speedball and so it should be on its way in a few weeks from now.
I'll report back when I've been able to install everything 

 

[petr667]

Hello,
  I have the same attenuator and I'm going to connect it. Could you advise me which taps are grounds, inputs, outputs and etc .....on attenuator it's not marked Thanks for help.

 

[Loggie]

Hi there,

Well its very simple to connect.
The connections on the standard potentiometer and the connections on the new one are the same.
So if you look at picture "Past net-6" you will get an idea how its connected.

There are 2 rows of 3 pins above eachother like this:

  Pins:  o    o    o        conections are:  R-Input    R-Output    R-ground

            o    o    o                                L-Input      L-Output    L-ground


Note: R-input and L-input means the wires coming from the RCA jacks !

So if you have the stepped attenuator placed the way I did then connections are the same as described in the Crack manual.

Let me know if my explanation was helpful (explaning in writing is harder than I thought    ).

Edit: Updated with picture showing connections.

 

[petr667]

Ooooh perfect!
thank you very much, everything works!

 

[Loggie]

Excellent 
How do you like the sound and quality of the attenuator?