One is a streaming all-in-one and the other is an amplifier. Judge them on how many boxes you want and what you already own, not on the spec sheet alone.
| Area | Better | Why |
|---|
| Noise floor | A | Onkyo Icon P-80 is the quieter design on paper - 104dB against 95dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | A | Both decode on board. Onkyo Icon P-80 goes higher - 768kHz against 384kHz. Very few recordings exist above 192kHz, so treat this as headroom, not as sound quality. |
| Streaming | A | Only Onkyo Icon P-80 has AirPlay 2, Chromecast and Roon. |
| Analogue inputs | evenly matched | The same number of line-level inputs (3). |
| Room to grow | evenly matched | The same expansion options on both. |
| Price | evenly matched | Priced within a few per cent of each other. |
A Onkyo Icon P-80 B NAD C 389
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both amplifiers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
Onkyo Icon P-80 has the edge on paper, though not by much. The rows marked "depends" are more likely to decide this than the score is.
What a spec sheet cannot show: how either sounds with your speakers, how the controls feel day to day, and what the app is like to live with - which is where most all-in-one amplifiers are actually won or lost. Power figures are the manufacturers' own and are not measured to a common standard, so treat small differences as noise. If you can hear both, that will tell you more than any row above.