Doepfer

> I've seen a few posts about this but haven't seen anybody mention
> any confirmed resolution.
>
> i've got a mean hum in my system when using this kit.
>
> these are the north american power supplies I'm using:
>
> input:120vac 60hz 15w
> output:12vdc 500ma
>
> are these good?
>
> thanks for any help.
>
> ~j

It's essential that the two power supplies have regulated 12V outputs.
Unregulated output will cause hum in any case !
The A-100DIY#2 does nothing but use the two supplies for +12V and -12V
directly (no additional electronics. The small pc board of the A-100DIY#2
only distributes the two voltages to the bus boards without any additional
stabilization or filtering. That's why the info page of the A-100DIY#2 says:

"This is an extremely inexpensive version of the power supply. The quality
cannot be compared to those of the normal A-100 power supply (A-100PSU2).
Stability of the voltages is significantly worse compared to the regular
A-100 power supply (A-100PUS2). Especially if VCOs are are used tuning
problems may occur ... In case of doubt we recommend the A-100 DIY Kit 1  as
the voltage stability of this kit is much better."

Best wishes
Dieter Doepfer