Power Cord for NAD C356DAC Int. Amplifier

I've had a NAD in a prior "B" system and its
fine performer at its price-point.

Don't spend more than a $100 - $125 (+/-) on a power cord
....performance won't improve if you go north of that
suggested range, with this gear.

(a) READY-MAD:E Its a wide open 'just pick-one-of'em';
arena of alternative Brand X versus Brand Y choices...and
I would buy a used from one of the serial gear-flipper
ads.... or,
(b) DIY NEW: IMO the best bang-fer-yer-buck is a DIY
power cord project with tailored quality better-grade
connectors (easy to cobble together yourself). At that
cable price-point a DIY project will generally get yield
a better result because of the premium connectors when
compared to the ready-made fare.

IMO and personal experience with the NAD kit, it may incrementally help (s/t SYTSTEM SYNERGY ALCHEMY comments below) but only by a comparatively limited amount at the NAD's build quality / price point strata; so don't go overboard expecting a quantum leap improvement. Again $100 is your threshold max IMO.

The quality and performance output of this upgrade is variable and system-dependent. Any power cable upgrade to better performance exercise is only a very small part of an ethereal alchemy created by the synergy (or lack thereof) provided by all of:
(i) your source,
(ii) the electronics themselves,
(iii) all the cables (Power/ ICs and speaker);
(iv) your speakers, and
(v)the listening room environment warts itself.

One "change" factor by itself alone may -- or may not --have a desired positive effect. Alternatively it may have no effect, or even be an adverse effect. This is a journey and not a destination exercise with a trial and error factor as its mantra.