I noticed that most of the pre/pro's out there output similar to the 990 spec:

• Output Level
TAPE MON REC, 1kOHM: 200 mV
PRE OUT, 1kohm: 1.0 V

Like Yamaha 2500, Denon 3805 etc.

But alot of the "higher end" pre/pro's have higher voltage output like the Anthem AVM30:

Rated Output (100k ohms load) 2.0 Vrms

Why is that..

additional example the Rotel 1068:

Preamp Output Level/Impedance 1.2 V (200 mV Input)