m.c.: This power supply was proposed in Elektor for the "Preamp" moving
coil preamp (no crap, tripple MAT02, OP27 servo amplifier for very low
noise).  Thus it can be assumed to be of reasonably good quality.
Note : All audio opamps have a additional 22Ohm, 1000uF//220nF
lowpassfilter for the supply lines (negative as well as positive).
This is good practise for high gain applications, but not necessary for
non critical circuits. I think it is also  a good idea to use
individual regulators for each module in order to have good
decoupling.  At least one should provide a clean analog and some
seperate dirty switching supply for logic, relays, leds etc.
 
Translation:
This power supply delivers +-18.5V (not recommended, tune to +-15V
m.c.).  The circuit is designed for good noise and hum rejection. So
you will find circuit elements you maybe wouln't expect in a power
supply.  The (torroid) transformator (not shown) should be 2x18V, 1A
(addapt to your needs, m.c.).  It is outside the amplifiers case in a
seperate case, to avoid magnetic fields und hum.  The power switch s1
(allready low voltage, not mains !!, m.c.) is connected with C7 and C8
to avoid switching noise.  The rectifier bridge with series resistors
R1... R4 reduces the initial turn-on current impulse and C1...C4
supress noise of the rectifier diodes.  The elkos C9 and C10 have
parallel caps C11,C12 (not ceramic, but polyester or polyproplyene,
maybe today a good ceramic would do, m.c.) to improve hf supression. T1
and T2 provide a clean, delayed turn-on of the regulators IC8 und IC9.
R12 und R13 together with C15 and C16 provide a lowpass filter to
further supress noise. (D5,D6,D7 and D8 provide reverse protection, m.c.).
 
m.c.
 
PS: R7 in the scan is hard to read. R7 = 1.5K