Different kinds of product: one is active with its amplifier built in, the other passive and needs one. Judge them on how you want to own the system, not just the specs.
| Area | Better | Why |
|---|
| Bass | evenly matched | Much the same reach (41Hz vs 40Hz). |
| What you buy | depends | Technics SC-CX700 is a complete system - just add a source. MartinLogan 40i also needs an amplifier: more money and another box, but you choose it. |
| Connections | depends | Technics SC-CX700 has Bluetooth, HDMI and phono built in. With MartinLogan 40i that all comes from the amplifier you pair it with. |
| Upgrade path | depends | MartinLogan 40i can be re-amped later and outlive several amplifiers; Technics SC-CX700 ages as one unit. |
| Size | depends | Technics SC-CX700 is easier to place; MartinLogan 40i is bigger, which usually goes with fuller bass. Your room decides. |
| Type | depends | A Powered Bookshelf against a Passive Floor-standing - a different job rather than a better one. |
| Expandability | depends | Technics SC-CX700: a sub output; MartinLogan 40i: bi-amping. |
| Price | B | MartinLogan 40i is cheaper - $2,600 against $3,499, about 26% less. Speakers only - an amplifier narrows that gap. |
A Technics SC-CX700 B MartinLogan 40i
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?
Technics SC-CX700 suits you if you want one box, ready to play, with nothing else to buy. MartinLogan 40i suits you if you already have an amplifier, want to choose the electronics, or expect to upgrade in stages. Neither is the better speaker in the abstract. In a large or open-plan room, MartinLogan 40i has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Technics SC-CX700 is the easier speaker to get right. Think about the whole system, not just the speakers: the roughly $899 saved by taking the cheaper pair would buy a subwoofer or a better amplifier, and either usually does more for the sound than the difference between these two.
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.