Upgrades Oct 2020 The Nord is being used exclusively to drive my 4ohm 12" Scanspeak Bass drivers. Time to tweak it, to suit this application and my personal preferences. Speaker Terminals One thing I don't like, is large lumps of metal in my speaker drivers signal path, either attached to the leads, in the form of bulky connector plugs, or mounted on the back of my Amps, like the currently fashionable, oversize binding posts. The Nord has quite large binding posts, I changed these to High quality, Hirschmann 32 amp, 4mm Banana sockets. I always felt the protruding binding posts, were vulnerable to damage as well, so I feel more comfortable with them gone. Input Buffer The supplied RevC Input buffers and Sparkos Labs SS3602 discrete op amps, produce good bass. When RevD Input buffers became available, with optional Sparkos SS2590 Pro Grade op amps, improved bass quality, became a possibility. After reading a very good review of this RevD upgrade on Hifi Pig, stating this combination produced "absolutely astonishing bass", I decided to fit the upgrade. HiFi Pig RevD Review With the RevD input buffer boards and Sparkos SS2590 discrete op amps, bass is very impressive. This shows the RevD boards and Hirschmann Banana sockets installed. That's about it for the Nord, its a great Amp, with not many upgrade opportunities, the RevD buffers and SS2590 combination, tailor it specifically for best bass reproduction.