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 | LEAK Stereo 230 has more power - 75W against 60W into 8 ohms. That is about 1dB, which is a small step in loudness but real headroom on peaks. |
| Room size | depends | We rate Primare I15 the better fit for desk or near-field listening and a small room, and LEAK Stereo 230 for a mid-size room, a large room and a very large room. Match the amplifier to the room you actually have, not the one you want. |
| Grip on hard loads | evenly matched | Both behave much the same into 4 ohms - output increases strongly (100W and 115W). |
| Noise floor | B | LEAK Stereo 230 is the quieter design on paper - 109dB against 97dB. Audible mainly with sensitive speakers in a quiet room. |
| Built-in DAC | B | LEAK Stereo 230 has a DAC on board; the other needs an external one, which is another box, another power lead and another purchase. |
| Analogue inputs | A | Primare I15 takes more analogue sources - 5 against 2. |
| Phono stage | depends | LEAK Stereo 230 has a built-in phono stage (MM) and Primare I15 does not. Decisive if you own a turntable, completely irrelevant if you do not - and an outboard phono stage is easy to add later either way. |
| Room to grow | evenly matched | The same expansion options on both. |
| Headphones | depends | Only LEAK Stereo 230 has a headphone output. Worth something if you listen late, nothing if you never do. |
| Amplifier class | depends | Primare I15 is Class D and LEAK Stereo 230 is Class A/B. Class D runs cool and draws almost nothing at idle; Class A/B runs warm and is the long-established mainstream choice. Modern examples of both measure well - judge by the rest of the page. |
| Price | evenly matched | Priced within a few per cent of each other. |
| Watts per dollar | B | LEAK Stereo 230 is the cheaper watt - about $23 per watt against $28. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Primare I15 B LEAK Stereo 230
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?
LEAK Stereo 230 has the edge on paper, though not by much. The rows marked "depends" are more likely to decide this than the score is. If you play records, LEAK Stereo 230 saves you buying a phono stage; if you do not, ignore that row entirely. If you already own a DAC or a streamer, the built-in one is money you are paying twice for, and Primare I15 becomes the more rational buy.
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.