Update,
Received my new power cable for the A5 48volt power supply. Initial impression, inner details and subtle nuances, I'm hearing in the music are already coming to the forefront. I would never have imagined this transpiring with a power brick power supply, as a ad on! New cable is more transparent, sound stage is deeper, wider, with more resolution, than my stock power cable. This is new out of the box. More playing time, I'm sure it will improve.
IMO, well worth the purchase!

Plugged into 48 Volt Power Supply

Photo showing actual size of cables, Stock versus new cable

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Update:
Listed three songs, among others, I listened to, during evaluation of the SX52B's. Check them out, I would be surprised, if you didn't appreciate them.
The entire album sounds amazing! Unfortunately, I can only give you a link a YT link.
https://www.youtube.com/watch?v=qiIJ6lmgHhU&list=OLAK5uy_nnf7-jPY2RHD3i-63Fte0ZdDuA8xDtg48&index=14 Note, Listen before passage 3:25, see what you think.

This song, is the one and only seductive Sade, strutting to a great live performance. most on here probably never heard, that didn't get airplay.
https://www.youtube.com/watch?v=eZiAuSwYEwk&list=RDeZiAuSwYEwk&start_radio=1As a drummer, I love bass and percussion, this hit's hard!
https://www.youtube.com/watch?v=v2yJJLAyu5Y&list=RDv2yJJLAyu5Y&start_radio=1Now having some burn in time with the A5 and the New SX52B's op-amps, my impression to date, this op amp works really well with soft dome speakers. Soundstage has opened up more, being more expansive and transparent. I'm also experiencing more inner detail with more burn in time as well. With out question, this amp is superior sounding over the amp section in the NAD. In this evaluation, I'm using the NAD as a Pre-amp, FYI. Something else I'm noticing, is better distinction between the instruments, triangle, cymbals, cowbells, playing chords on the strings is more pronounced, as well as other area's within the listening source. Decay structure is better developed. Granted, if recorded material is poorly mixed and produced, no electronics can save that sinking ship.
I Imagine, anyone with Encores would be very pleased with the combination. This is using a solid state NAD-AVR receiver, which typically are pretty neutral in presentation. I'm playing at levels between 75-85 decibels approximately. I don't need to listen at concert levels, since I experience those levels behind my drums, conducting live performances. Although I do wear ear monitors.
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