I have a 555 from the late 80s. It handles the difficult loads very well. There was no problem with Thiel 3.6 nor Thiel 2.3. However, the 555's sonics are mediocre at best compared to the so many great amps of today. The Adcom simply collapses the music into a 2-dimensional presentation and has only-ok resolution. I really had no idea how poor this was until I cycled it through my audio system when I was trying the ARC VT130, ARC Classic 150s and then the very impressive Counterpoint NPS 400. Talk of the 535II being the great Adcom amp in the lineup was quickly dismissed as this too had the same qualities as the 555.
At its time, the 555 was a great value for midfi systems. Today it is really only suitable for a non-serious 2nd or 3rd system or as a starting point for a Home Theatre application. I currently use it in the latter with good results until I get serious with some Pass or Plinius amps here. I am sure the McCormack DNA series would be a major improvment over the 555.
John
At its time, the 555 was a great value for midfi systems. Today it is really only suitable for a non-serious 2nd or 3rd system or as a starting point for a Home Theatre application. I currently use it in the latter with good results until I get serious with some Pass or Plinius amps here. I am sure the McCormack DNA series would be a major improvment over the 555.
John