Replacing pot with stepped attenuator-two decks needed?

[Mbira]

Hi folks,

In this stage of the G9 schematic, there is a 47K Log pot for the output.  I want to replace this with a stepped attenuator.  I opened my G9 and I ran a signal through and measured 0db on my DAW and then brought down the pot until it was giving me -3db, measured the resistance between the wiper and the side that connects to the Low Cut.  I wrote down the values as I went and then mocked up a 12 step attenuator. 

I just realized that the other end of the pot is connected to ground.  Doh!  So my question is-is it essential for me to use a two deck attenuator so that I can have one deck feed the ground, or can that pot effectively be replaced by single resistors that go between the Low Cut and C10?  I'm thinking that the little resistor to ground isn't that important since there is the 1M grid resistor right after C10? 

Attached is the portion of the G9 schematic, and then what I was hoping to do with my attenuator.  I appreciate any thoughts on this!  Also-yes I understand that the attenuator is a lot more expensive than the pot.  I really want to be able to have something that is easily recallable, so if I can get the attenuator to work, that's definitely what I want to do. 

 

[Mbira]

Looks like I can't delete my own post.  I just found schematics for wiring these in a way where the ground is still there:
http://www.goldpt.com/r_series.html

 

[ruffrecords]

You need to take care what type of switch pot you use for this. The HPF relies on the 47K of the original pot to do its function correctly. So you need to replace the pot by a switched ladder version which is wired in exactly the same way. In your schematic it does not look like a ladder and it appears to be wired in backwards.

Cheers

Ian

 

[Mbira]

You need to take care what type of switch pot you use for this. The HPF relies on the 47K of the original pot to do its function correctly. So you need to replace the pot by a switched ladder version which is wired in exactly the same way. In your schematic it does not look like a ladder and it appears to be wired in backwards.

Cheers

Ian

Ah jeez....I didn't even make the connection that it is also acting as part of the R-C in the tone stack. Doh! Thanks for the tip on the switched ladder terminology!  I'll go sort it out.  Cheers!