In terms of imaging, the Alpha Wave had almost the opposite effect of the Sigma Wave. With the LAN optimizer the stage seemed a little more compact and close. That was fine by me as it corresponds to my personal taste especially because spatial selectivity remained at the EOS DAC's usual high level. I also noticed that the music now felt a bit more primal in places. This seemed to have something to do with sample rates, particularly the Red Book standard. Depending on the music, I actually found it pleasant. Raspy voices such as Richard Bargel's on "Bad Bad Whiskey" from his album Richard Bargel Live gained even more expression as a result. But I couldn't detect this 'roughness' with hi-rez files.
I had noticed something similar before when comparing different DAC chips. Red Book recordings often sound smoother on certain older chips which were made for this type data than with modern high-performance chips that can process far higher data rates. Is it because these old chips smooth out digital 'gradations' as the last artefacts of digitization while modern chips make them audible because they work more precisely? I interpreted the effect of playing Red Book into the Alpha Wave as meaning that the digital signal reached the DAC more cleanly and lower resolution data were therefore more clearly exposed.
One exciting question remained. What happens when the Ideon Audio Alpha Wave LAN Optimizer and Sigma Wave USB Isolator work in series? As was to be expected, the effects added up. Bass was powerful and played at a level equivalent to that of the Alpha Wave solo. The little extra the Sigma Wave brings to the table on its own was barely audible. The increased resolution of the Alpha Wave stayed but seemed to integrate a little better with the Sigma Wave. The deeper blackness of the Sigma Wave came across a little better. One thing is clear: both devices have their place and in combination, my digital performance took a leap forward that I would not have thought possible. I am impressed by how much sonic potential there is in the processing of digital signal prior to D/A conversion. You don't have to believe it. You can easily hear it.
If I had to choose just one of these devices, I'd go for the Alpha Wave. Whilst its overall influence is somewhat less, I liked the better bass control and subtly increased resolution particularly with hi-res data. The effect of the Sigma Wave USB Isolator is overall clearer, the increased grip and blackness it brings impressive. In my opinion however, it shows its full potential primarily in combination with the Alpha Wave. But whatever the case, you don't have to blindly trust my assessment. CM-Audio here in Germany can send interested parties the duo for in-home testing. This way you can explore what effect Ideon Audio's Alpha Wave and/or Sigma Wave have on your own system. I wish you exciting and informative listening sessions!
The Ideon Audio Alpha Wave LAN Optimizer psych profile…
The Ideon Audio Sigma Wave USB Isolator psych profile…
Facts:
Ideon Audio Alpha Wave LAN Optimizer
Ideon Audio Sigma Wave USB Isolator
