The stock unit sounded bass heavy with some high frequency roll-off. Details are semi 'veil-ed'. The stock AU-4400 had a more balance presentation but lack the punch of the AU-217. Personally I prefer the AU-4400 to the AU-217.
Once recapped, the AU-217 can be a real shocker! Most of my visitors who heard it though it was atleast a 70-90W RMS per channel unit as it was able to make my Celestion SL6S sing with ease - packs a much bigger punch than the Arcam Alpha 8 power amp of 50W RMS per channel!
The quality of reproduction is heavily influence by the four 100uF 50V caps which are arranged in a 'L-shape' next to the large PSU caps. The other influential EC caps are the two 470uF 50V caps near the middle of the motherboard.
Please note there is a group of ceramic caps on the opposite side of the amp (away from the transformer) which influence the HF and should be replace with caution.
On my AU-217, replacing the large PSU caps resulted in extremely minor improvements.
In the past, the unit was only slightly warmish after running the unit for atleast 8-12hrs a day during the weekends.
Since you are unable to bypass the tone controls, it was necessary to replace all the non-EC capacitors there. I replaced them using Wima's of equivalent value and the effort was immediately rewarded with a fluid and transparent presentation - eventhough the tone controls were left at '0'.
Weakness includes limited connectivity to single pair of speakers,and, no speaker selector.
Otherwise quality sound at low power consumption!!!
|View from rear after recapping|
|View from side after recapping|