I feel your ADB needs and serial needs are only useful with OPCODE midi interfaces and midi hardware from the same age... Maybe it should be easier to find USB-Midi solutions than SERIAL-Midi solutions, but if you already have that serial hardware you have to find a solution.
emagic usb midi interfaces and M-audio are affordable and with good quality
?
motu/opcode serial midi hardware is cheap because its only compatible with old macs
and it performs excellent. for those of us looking for great midi performance + networking + alot of it..
these serial midi devices are a win win for how much they cost.. and the biggest pain in the ass is finding the "adapters" to make them work with g3/g4's
hence why im looking into clones because they offer a) lots of pci slots for expansion (which there is alot of !) when u add up pro tools cards + audio i/o cards
and pci serial card for midi and sata pci adapter for sata u arent left with much slots left over for powercore or uad.. thats for sure
b) they come with the serial ports needed for these midi devices already..
so basically its similar to a powermac 9500 or 9600 which are hard to find for cheap
but a mac clone? maybe it can be found with its unknown name "daystar" etc
re: your coment about usb midi solutions
i have read that people have had problems with midi latency with usb midi devices
especially on osx on powerpc
maybe this was cleared up with software updates tho
the post i read just a few moments ago was talkina bout the mt4 by emagic
being nice + fast in os9 but slow + extra 10ms latency in osx