Aragon 4004II vs 8008st

I just recieved a 4004II and love it. Ive owned 4 krells ksa series and like the 4004II very well. Whats diffrent about the 8008? Better power supply/ heat dissipation/higher bias class A maybe?
The 8008st uses a single "dual wound" transformer for the power supply where as the 4004 mk II uses seperate transformers(dual mono design). The 8008 series also uses a DC servo circuit for flat operation down to 5 hz. I agree with you i like the 4004 mk II very much.
They look a lot alike on the outside, they look a fair amount alike on the inside. BUT, the 4004 series uses 4 matched sets of 4 metal can power transistors, (16 altogether) while the 8008 series uses non-matched plastic case Hitachi power transistors, mounted on a wholly different circuit board/heat sink assembly. There are 16 Hitachi units in the ST, and 24 in the BB/MkII.

First guess: The metal-can transistors will handle more current than the plastic case ones, which is why there are more of the plastic case units in the BB: It takes more to output as much as the 4004.

At any rate, the plastic case units are cheaper and more readily available. That is one of the primary reasons for the switch to the 8008 series: Mondial could no longer buy the older style power transistors in the quantities needed.

The 8008ST uses a single 2000VA double-wound transformer, the BB/Mk II uses a pair of 1100VA transformers, and double the storage capacatance of the ST. I think the 4004 is more like the BB than the ST in regard to power supply transformers and capacatance.

Far as I know, the 4004 series is also DC servo, and good to 5 hz.