I've had Jason's other pair of N-Cores for a couple days. Not the tour pair you guys are listening to, but I assume they are the same construction. I listened with my Buffalo2 transformer coupled, volume controlled DAC direct to the amps, playing through two different speakers. I used Black Sands Silver V power cords on the amps in a dedicated 20A circuit.
Listening to them on a pair of newish (50 hours) Polk LSiM 707 4 way towers I found the amps to really bring the speakers to life compared to a diy 100W linear SS amp and a 100W AR tube amp. The low output impedance of the NCore is easily heard across the entire bandwidth. Of course bass is much clearer, punchier. The smaller amp allowed the ports to ring too much, the ports sounded separate from the direct sound and distracting sometimes with tendency to ring at their resonance. The NCore controls the bass drivers so well that no port antics are permitted. Bass is tuneful and controlled at all frequencies. The 60W amp thermal protected out while playing loud bass heavy song at the high levels these speakers can deliver. The NCores had no problem. Dance music makes a godalmighty powerful beat. Unbelievable from these little plastic drivers.
Midrange is also more detailed. Tonal texture is abundant. Solo cello, piano, voice, trumpet, are exquisitely detailed. The drivers are forced to comply with no mercy. Treble is clear, clean and very powerful, but no artifacts as I've heard in other class Ds. There is no trace of the high feedback stuffiness from opamps used in the Hypex UcD inputs. It reminded me of the Spectron in clarity, but without the quirks and I didn't sense the high frequency "thing" that I have heard Spectron do. I love how quiet these amps are, and small and light.
This is definitely not an amp to relax with a glass of cognac and a pipe while Perry Como sings in the background. They will force your speakers to reveal flaws in the system and rub your face in it. But I found it more enjoyable listening to the ultra confident NCores and the flaws they expose than using lesser amps that conceal flaws better but sound wimpier. They deserve very high quality source signal and speakers.
With these amps available now, I would consider owning lower sensitivity speakers like Revel Studio2, or even panels. They can force a lower sensitivity speaker to make the same kind of detail and control that lesser amps will require easier speakers to achieve. I look forward to hearing the NCores on higher sensitivity speakers too.
Thanks for the audition Jason! See you tomorrow.
