Hello,

you find my answers written inline.

And there is an additional note in this regard: from about end of November a new power supply will be available (A-100PSU3). It will
offer 2000mA@+12V, 1200mA@-12V and has additional +5V with 4000mA available. It turned out that there are many modules from other
manufacturers available that take more current than A-100 modules (e.g. the new Roland modules). Some of them also require a high
current at +5V. Internally the A-100PSU3 is a +/-15V switching supply (wide range input 100...240V for mains voltage) followed by
the classical linear regulation circuit of the A-100PSU2 that generates required +12V and -12V. Only the +5V is a pure switching
supply without linear regulation. We discovered that a pure 12V switching supply was not good enough for the modular system
(especially the load regulation was not satisfying for all 12V switching supplies we tried). That's why we added the well-tried
linear regulation to the 15V switching supply.

Best wishes
Dieter Doepfer

> -----Ursprüngliche Nachricht-----
> Von: Doepfer_a100@yahoogroups.com [mailto: Doepfer_a100@yahoogroups.com ]
> Gesendet: Donnerstag, 29. Oktober 2015 16:36
> An: Doepfer_a100@yahoogroups.com
> Betreff: 1 A-100PSU2
>
>
> Hi everybody,
>
> short question: Are the 1200mA of the A-100PSU2 completely available or is there any need for some kind of headroom

Each A-100PSU2 is tested with a dummy load of 10 Ohm which corresponds to 1200 mA. We also tested all kind of A-100 cases with built
in A-100PSU2 under these conditions to find out if there may be thermal problems. All results were OK. Consequently I can confirm
that there is no need for a headroom. As long as the sum of all currents of the A-100 modules driven by the A-100PSU2 is less than
1200 mA everything is OK. The current for each A-100 module is specified on the info page of each module. But one has to take the
worst case, e.g. the max. value (120 mA) for the headphone amplifer.
But I can speak only for A-100 modules and the statements are valid for "normal" conditions. There is always some chance that a
module takes more current than specified because of a fault (e.g. defective integrated circuit or electrolytic capacitor). But this
is normally recognizable in the malfunction of a module

> To be honest: My actual setup allows no headroom for headroom :-(
>
>
> Another quickie: Is there any difference between the voltage consumption of connected modules (buffered indeed) in use
> and unpatched modules (but connected to the bus)

There is no difference if a module is patched or not. There is only one module that comes to my mind where the current depends upon
the usage: the headphone amplifier (as already mentioned by Florian).

> Thank you so much for any clarifying reply.
>
>
> Best regards from Cologne/Germany
> Wolfram
>