[sdiy] power supply (un)symmetry

[Matthias Herrmann]

hi all,

sorry if i posted this before, but i think it didn't come through to the
list? or is something mysthic going on here? no posts today?

i recently built a little powersupply for the soundlab i am building. it
converts 9VAC to +9V/-9V DC and +12V/-12V CD (for the midi2cv converter).
its made out of four diodes, 4 polarized caps and some 78xx/79xx. actually
it is a mod of the doepfer A-100 miniNT bus.
unfortunately it is not 100% symmetric. actually it provides +9,2V/-8,8V
(+12V/-12V accordingly unsymmetric). i don't know whats wrong yet.

i wonder if this would be critical?
and if so, how to fix it with few parts?

any comments appreciated...
matthias