I've been hard at work populating my boards. There have been so many interesting modifications discussed in this thread, many of which seem to have become a de facto part of the build despite being off-board mods. I'd like to make sure that the collection of mods that I plan to implement are going to work properly together.
building the mastering version, but I understand that some of the modifications are still worth using. Here's what I plan to do and how I understand it all to work...please let me know if this looks wrong in some way.
-Replace the potentiometers with this stepped switch
for coarse steps.
Sidechain (rotary boards):
-Use resistor values for 1dB steps on threshold control (from schematic, different from silkscreen on my boards which appears to be for 3dB steps)
-Add hi/lo threshold range switch (simply adds a switchable resistor between R9 and R16 -- this is shown with a DPDT switch but I think it could be done on an SPDT as well) -- I think this is most useful with the 1dB threshold steps
-Add switchable HPF at 60 (?) Hz -- I believe that this value is at least approximately correct based on the values in Heikki's sheet, right? (680 resistors, 2u2 caps)
I'm still unclear about what the main board changes around U9 and U10 do (I know it's been explained, I just didn't properly absorb the information). I think I'll keep that as stock unless it will adversely affect the other modifications above.
I am going to see about getting a matched quad of 6sk7 tubes (if possible) as well as a quad of 6ss7, to see if I get different results from either. Is the 6ss7 just a drop-in replacement in this context, or are other adjustments needed on the main board to accommodate them? It seems like they are a direct swap, but I don't want to assume that and fry something.