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 |
|---|
| Power | A | Naim CI-Uniti 102 has more power - 150W against 90W into 8 ohms. That is about 2.2dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Room size | depends | We rate Naim CI-Uniti 102 the better fit for a large room and a very large room, and JBL SA550 C for desk or near-field listening, a small room and a mid-size 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 (260W and 150W). |
| Noise floor | A | Naim CI-Uniti 102 is the quieter design on paper - 110dB against 106dB. 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. |
| Streaming | A | Only Naim CI-Uniti 102 has AirPlay 2 and Chromecast. |
| Analogue inputs | B | JBL SA550 C takes more analogue sources - 3 against 1. |
| Phono stage | depends | JBL SA550 C has a built-in phono stage (MM) and Naim CI-Uniti 102 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. |
| Use with a TV | depends | Only Naim CI-Uniti 102 has HDMI eARC, so the television can drive it directly and one remote controls the volume. If the system is for music only, this changes nothing. |
| Room to grow | evenly matched | The same expansion options on both. |
| Headphones | depends | Only JBL SA550 C has a headphone output. Worth something if you listen late, nothing if you never do. |
| Amplifier class | depends | Naim CI-Uniti 102 is Class D and JBL SA550 C is Class G. Class D runs cool and draws almost nothing at idle; Class G/H switches its supply rails to cut the heat a Class A/B design wastes. Modern examples of both measure well - judge by the rest of the page. |
| Shelf space | depends | Naim CI-Uniti 102 takes up about 42% less shelf area (900cm² against 1565cm²), and it is 47mm shallower, which is the measurement that decides whether a rack door shuts. |
| Price | A | Naim CI-Uniti 102 costs less - $1,499 against $1,999 at list. |
| Watts per dollar | A | Naim CI-Uniti 102 is the cheaper watt - about $10 per watt against $22. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Naim CI-Uniti 102 B JBL SA550 C
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?
Naim CI-Uniti 102 is the easier recommendation: it leads on most of the measured areas and costs less. Take JBL SA550 C if one of the "depends" rows above describes your system. Start with the room. In a large or open-plan room, or with speakers that are hard to drive - low sensitivity, or an impedance that dips - Naim CI-Uniti 102 has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 90 watts is already more than most people ever use, and the extra 60 watts would be headroom you pay for and never hear - we rate Naim CI-Uniti 102 poorly for near-field use for exactly that reason. If you play records, JBL SA550 C saves you buying a phono stage; if you do not, ignore that row entirely.
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.