Audiophilepure

That last sentence is important as it describes the Q Acoustics Concept 50 perfectly; it passes every test with flying colours. It’s a £2,000 loudspeaker that sounds almost like a £4,000 loudspeaker. The design isn’t just ‘another box’ but nor are the innovations that go into the design merely there for their own sakes. A loudspeaker that is easy to drive and possessed of a classic sound yet isn’t so ‘classic’ as to be boring and isn’t undemanding of electronics in quality terms. With Concept 50, Q Acoustics more than earns a place at audio’s top table.

https://www.enjoythemusic.com/magazine/equipment/1222/Magnepan_LRS_Plus_Quasi_Ribbon_Floorstanding_Loudspeaker_Review.htm

Before discussing the Plusses’ downside, I need to say a word about setup. In the old days, Maggies were typically listened to head-on, without any toe-in, for greatest neutrality. A lot of folks still prefer this alignment, but…it won’t work ideally with the LRS or the LRS+. Because of the smaller size of their quasi-ribbon panels and the fact they are two-ways, you may end up with either too much bass or too much treble and not enough in between — i.e., with too dark or too bright a tonal palette — if you don’t cant the speakers in a fair amount (at least 15–20 degrees). Though this may be room-dependent, Maggie also recommends that the speakers be situated with their tweeters (visible via a flashlight shined through the grille as the section of the panel with narrower, more closely aligned foil strips) to the outside and away from the wall and, with the requisite toe-in, their woofers to the inside and closer to the wall. My description of the sound of the LRS+ reflects Maggie’s set-up recommendations, albeit with toe-in painstakingly tweaked almost degree by degree until I achieved a balance that was neither too top-down or too bottom-up but audibly and measurably close to neutral.

https://www.soundstageultra.com/index.php/equipment-menu/1135-atc-scm50-passive-active-loudspeaker

In summary, the ATC SCM50 is a benchmark design and a world-class loudspeaker, whether driven actively or passively. In the active configuration, it represents an incredible bargain in the high-end audio field—and that would be my choice if I were laying my money down. In my experience, there’s no other loudspeaker that comes even close to its immense power, neutrality, bandwidth, speed, and sheer visceral impact at anywhere near the price. If you choose to go the passive route, expect to budget significantly more than the $8000 difference in cost between the active and passive SCM50 variants for your amplification. The big Naim combination powering the passive SCM50s offered stunning sound—at significant cost—and the transparency of the ATC loudspeakers allowed all the virtues cherished by Naim enthusiasts to really shine.