These sit in different price classes - Sony Signature Series SA-Z1 costs roughly 29.7x what Audioengine A2+ Wireless does. Expect it to lead on paper; the question is whether the gap is audible enough in your room to be worth it.
| Area | Better | Why |
|---|
| Bass | A | Sony Signature Series SA-Z1 digs deeper - 51Hz against 65Hz. |
| Built-in power | A | Sony Signature Series SA-Z1 has the bigger amplifier (212W vs 30W RMS). |
| Connections | depends | Sony Signature Series SA-Z1 adds digital inputs; Audioengine A2+ Wireless adds Bluetooth. |
| Size | depends | Audioengine A2+ Wireless is easier to place; Sony Signature Series SA-Z1 is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | B | Audioengine A2+ Wireless: a sub output. |
| Price | B | Audioengine A2+ Wireless is cheaper - $269 against $8,000, about 97% less; arguably a different class. |
A Sony Signature Series SA-Z1 B Audioengine A2+ Wireless
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 speakers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
Sony Signature Series SA-Z1 is ahead, but only on 1 of the measured areas, and it costs about 29.7x the price. That is a lot of money for a narrow margin on paper - Audioengine A2+ Wireless looks like the sensible buy unless something else about the Sony Signature Series SA-Z1 appeals to you. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 65Hz anyway, which makes the cheaper Audioengine A2+ Wireless much easier to justify. In a large or open-plan room, Sony Signature Series SA-Z1 has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Audioengine A2+ Wireless is the easier speaker to get right.
And remember what a spec sheet cannot show: how each looks in your room and whether the finish suits it, what dealer support and warranty are like where you live, and how they actually sound to you. If you can hear them first - ideally with your own music - that will tell you more than any number above.