sex 3.0 stepped attenuator question

[Thermioniclife]

Hey folks,
Can any of your stepped attenuator kits be adapted to work on a SEX 3.0?
Thanks.

[Paul Birkeland]

Hello Lee,

The chassis plate of the S3X is just not quite large enough to make it a practical installation.  I think even a PEC pot is a bit of a tight fit, but a workable substitution.

-PB

[Thermioniclife]

Thanks Paul,
I just ordered a Sex 3.0 and C4s during the last sale and have plenty of time to come up with wacky ideas while waiting for their arrival.
Best wishes for the Holidays and the upcoming new year.
Lee

[Natural Sound]

Bottlehead used to sell a passive preamp. I forget what they called it. Basically it was a stepped attenuator with a multi input switch in an outboard enclosure. Unfortunately it has been discontinued.

There are several companies that sell them online. One company in Poland gets good reviews. https://www.khozmo.com/stereo_selector.html

Some creative bottlehead kit builders have shoehorned this https://glass-ware.stores.yahoo.net/a3mini.html into the S.E.X. 2.1. Not sure if it will fit in the 3.0. It will require some careful drilling. But might be worth it depending on your skill/comfort level.

I hope this helps stimulate you "wacky" ideas.😉

[Tom-s]

I ordered S3X and Mainline at the same time to try the exact same thing.
With the shunt attenuator from the Mainline i got the size of it for S3X.
Unfortunately it wouldn't fit. So i went with smaller Elma switches to make it work.

https://ep1.pinkbike.org/p5pb16519342/p5pb16519342.jpg
https://ep1.pinkbike.org/p5pb16521276/p5pb16521276.jpg

[Thermioniclife]

I was thinking that I could mount a Twoquiet attenuator on the front panel of the wooden base.
The amp is going to reside on a shelf above my bench in my evil laboratory, so having the switches on the front would be ideal.
I guess my next questions are 1) what is the width of the Twoquiet trim bezel? and 2) will the resistors included in that kit be suitable to use in the S3X?
As far as mounting on the wooden base I have a lathe, a milling machine and a router so I can pretty much make or modify any parts that may be needed.
Thanks

[Thermioniclife]

Oops,
I meant what is the width of the metal backing plate on the Twoqiuet kit or Mourquiet or Beequiet.
I can remove the input select portion of the trim bezel.

[Paul Birkeland]

The attenuator plate is 6" wide, so there's certainly room on the wood base for it. 

It will be a serious headache to build like that though!

[Thermioniclife]

Thanks PB,
How about the resistor values, will any of these kits have appropriate values?

[Paul Birkeland]

Yes, you would want the BeeQuiet.

IMO your best bet would be to mount the metal attenuator plate on l-brackets that connect it to the top chassis plate, then just have holes drilled in the chassis for the shafts to poke through.  Luckily for you the shafts on those switches we provide are quite long!

That will make the amp a bit easier to take apart and much easier to build.

-PB

[Thermioniclife]

Thanks Paul.

[Tom-s]

What you could do. Is turn the CCS 180 degrees, so it points just the other way (not upside down).
This would make enough room in the front for your attenuator.

I've also used a 50kohm input impedance in mine with good effect.

[Thermioniclife]

Thanks Tom-s noted.

[oguinn]

Are there resistor value differences between what the Submissive has and what’s on the stepped attenuator upgrade kits? It’d be awesome to replicate the Submissive for projects like this

[Paul Birkeland]

Yes, the Submissive used the attenuator setup that's in the Mainline, which is a lower impedance design than the attenuator upgrade kits for the BeePre, Stereomour, and Smash.