The clicks are very loud.
In terms of the modes, Freya+ has the passive mode which measures extremely well obviously, and this is the same as the Freya s passive. Then they both have a ~unity gain buffer setting, both very good with the S being slightly better. For the third mode, the + has the tubes, which are really not very tube sounding, and the S has a gain mode that didn't measure very well compared to no gain.
You can replace the volume knob, I found that this one improved the look of the unit and had a better hand feel and a bit larger.
Uxcell a15020500ux0472 Aluminium...
https://www.amazon.com/dp/B0147XGEFA?ref=ppx_pop_mob_ap_share