unix-guy
Master of RTFM
@State of Epicicity - you might use the wiki to dig deeper. In the Amp list it says this:
https://wiki.fractalaudio.com/wiki/..._models_list#USA_PRE_LD1_RED_.28TX-4_board.29
From a quick bit of googling it appears the TX-4 is for a Recto lead...
https://wiki.fractalaudio.com/wiki/..._models_list#USA_PRE_LD1_RED_.28TX-4_board.29
That's how our reference amps work. They are the later models with the TX4 board (different LD2 Red). When using the LD1 modes the Presence control doesn't do anything and is as if the control were at 10." [454]
From a quick bit of googling it appears the TX-4 is for a Recto lead...