No single best amplifier here. What decides it is what you have to drive, what you need to plug in, and how much of the system you want in one box.
| Area | Better | Why |
|---|
| Power | B | Peachtree nova150 has more power - 150W against 100W into 8 ohms. That is about 1.8dB, which is a small step in loudness but real headroom on peaks. |
| Noise floor | B | Peachtree nova150 is the quieter design on paper - 105dB against 99dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | evenly matched | Both have a DAC on board with much the same capability. |
| Analogue inputs | A | Yamaha A-S801 takes more analogue sources - 6 against 2. |
| Room to grow | B | Only Peachtree nova150 offers a pre-out/main-in loop - which decides whether you can add a subwoofer or a power amplifier later without replacing the box. |
| Amplifier class | depends | Yamaha A-S801 is Class A/B and Peachtree nova150 is Class D. Class A/B runs warm and is the long-established mainstream choice; Class D runs cool and draws almost nothing at idle. Modern examples of both measure well - judge by the rest of the page. |
| Shelf space | depends | Peachtree nova150 takes up about 33% less shelf area (1200cm² against 1792cm²), and it is 75mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | A | Yamaha A-S801 costs less - $900 against $1,199 at list. |
A Yamaha A-S801 B Peachtree nova150
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?
The usual trade-off: Peachtree nova150 measures better, Yamaha A-S801 costs about 25% less. With most speakers in most rooms that gap is smaller in practice than it looks here.
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.