OWNERS MANUAL FOR WEISS MEDUS D/A CONVERTER
Reconstruction Filters
Reconstruction filters have been mentioned in the "Up-sampling, Oversampling and Sampling Rate
Conversion in General" paragraph above. If you have read that paragraph you know what the
purpose of the reconstruction filter is. The main point about this analog filter is that its frequency
response should be as smooth and flat as possible in order to have a virtually linear phase
response. The MEDUS employs a 3
rd
order filter for that purpose.
Analog Output Stages
The MEDUS employs class A output stages with a very low output impedance. Class A inherently
guarantees very low distortion figures even when operating the amplifier in open loop, i.e. without
feedback. The feedback is added to lower the distortion figures even further. The distortion figures
of the MEDUS, which by the way are excellent, are predominantly caused by the D/A converter and
not by the output stage.
A very low output impedance assures that the performance of the MEDUS and the subsequent
amplifier combination is not compromised by the cables between the two or by the input
impedance characteristics of the amplifier. A low output impedance can be difficult when it comes
to stability issues, but we have taken care of that problem in the MEDUS.
