These are not the same size of amplifier: Emotiva BasX TA2+ has roughly 2.3x the power of Rotel A12 MKII. That is about 3.5dB, so it is a question of room size and how hard your speakers are to drive, not of one being the better amplifier.
| Area | Better | Why |
|---|
| Power | A | Emotiva BasX TA2+ has more power - 135W against 60W into 8 ohms. That is about 3.5dB, so it plays usefully louder before it runs out and has more in hand on peaks. |
| Room size | depends | We rate Emotiva BasX TA2+ the better fit for a mid-size room, a large room and a very large room, and Rotel A12 MKII for desk or near-field listening and a small room. Match the amplifier to the room you actually have, not the one you want. |
| Noise floor | A | Emotiva BasX TA2+ is the quieter design on paper - 120dB against 100dB. 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 | evenly matched | The same number of line-level inputs (4). |
| Room to grow | evenly matched | The same expansion options on both. |
| Price | B | Rotel A12 MKII costs less - $1,100 against $1,299 at list. |
| Watts per dollar | A | Emotiva BasX TA2+ is the cheaper watt - about $10 per watt against $18. A blunt measure, and it says nothing about how either sounds, but it is the honest one for raw output. |
A Emotiva BasX TA2+ B Rotel A12 MKII
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?
Emotiva BasX TA2+ leads across most of the measured areas for a fairly modest premium, so it is the easier pick if the budget stretches. Rotel A12 MKII is the one to take if it does not. 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 - Emotiva BasX TA2+ has the headroom, and headroom is what stops an amplifier hardening up on peaks. At desk distance or in a small room, 60 watts is already more than most people ever use, and the extra 75 watts would be headroom you pay for and never hear - we rate Emotiva BasX TA2+ poorly for near-field use for exactly that reason.
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.