Yes Peete, PSU integrated current limiter can be tweaked too. Roc in stock configuration has constant 0,170 A through his rails limited by "pile of resistors" marked in this picture:
By soldering additional resistor in those two marked positions you raise constant current flowing through (10 Ω ≈ +60 mA; 5 Ω ≈ +120 mA). But beware, by doing this - amp runs hotter so you should closely monitor the temperatures after you increase the current limit.! Also beware - you should not go lower than 5 Ω.
I went for 5,7 Ω that I had on hand so I have ≈ 270 mA current limit which translates into 1,8 W (instead of stock 0,75 W) into 25 Ω impedance of my hardest to drive orthos. The additional power makes nice difference with HE-5.
As for diodes, I think A-GD uses
On Semiconductor 8A rated ultrafast diodes, which are not bad at all. I went for
Fairchild Stealth 4A 600V diodes, but now I wander whether I underrated them - they get very hot without heatsinking. I also can not give meaningful assessment of the SQ change they made because I was doing the recap, bypass and recabling thing in the same time (lifting Roc's board is a hell of a job). What I can say is that the cumulative result was astonishing: increased clarity, effortless SLAM!, "blackness"... but you already know that from your Phoenix mods Peete.
All this tweaking and learning along has made me admire Phoenix even more: you can do all this and more to Phoenix... just that tweaks mentioned here must have much greater effect on that dual mono triple stage parallel class A PSU that Phoenix have... not to mention that you can go safely to 0,35 A limit on Phoenix (by KingWa's words)... Eh, if I could just save up some money...
Errr... anyone interested in buying "slightly modified" Roc?