I have an organ with 32' stop and this sub does a terrific job shaking the walls :-). Great value!

Love the 12S, my only complaint is the transmitter, sometimes, creates a big low frequency (60 Hz audio?) hum in my audio system, I have to jiggle the unit to find the right quiet position.

Thank you for making a great subwoofer, that I can incorporate into my audio system.

Robert Thom

A single 12S is being used in a 2-channel music only listening room. Room dimensions are 21’x19’ with a sloped ceiling that varies between 8 and 10 feet. A 6’x17’ hallway is attached to the room and where the 12S is positioned just behind the listening position adjacent to the main room. The room is fully acoustically treated with Sonex panels on the side walls and wood diffusion on the front wall. A small amount of panel absorption is located on the rear walls. Also included are 6 bass traps with 4 Argent Room Lens.

EQUIPMENT -> Qobuz Music -> MacMini w/HQPlayer -> MicroRendu 1.4 -> Denafrips Pontus II -> Topping Pre90 -> Quicksilver KT Monoblocks -> Harbeth HL5+XD -> RSL12S

Prefered Music Genre is Jazz, Classic Rock, Alternative Indie.

Setting up the 12S was a breeze and super easy to integrate with the Harbeth’s. I am running the Harbeth’s full range and blending in the 12S I’m guessing somewhere around 35Hz to 45Hz. The sub sounded very good but I feel that adding an isolation base and a bit of weight on top of the cabinet cleaned things up just a bit with perceived added focus and speed.

The bass output of the 12S is outstanding. On average, bass output or volume is roughly just pass the midway point. I was going to order two of these and RSL recommended that I try a single sub first. I’m glad I took their advice as I couldn’t be happier with how this single sub performs with my system. The bass is impactful and adds a sense of depth and scale to the music. I don’t consider myself a hard rocker but Classic Rock never sounded so good on my system.

Any negatives or something I’d wish for, yes. I wish the crossover frequency adjustment had a series of small click so the user could make it easier to dial in and find a predetermined setting. The volume dial on the plate amp has these clicks.

In my opinion the 12S Speedwoofer is an incredible sub at any price, but for $799 has to be one of the best bargains in HiFi.

Great product, fast shipping, good packaging, good price, professional, highly recommended. I'll buy again, thanks.

First and foremost, it's huge, the subwoofer I mean. Second it lacks in the mid bass, I had to add a second sub (Kanto YU8) to pick up the subtle tones between 120-60. That said, anything below 60 she sings LOUD and will rattle your bones, glasses in your kitchen and make your guest smile. What I don't like; the construction, it squeaks, like it's trying to break the box it was built around. I took a screwdriver to the exposed screws but it still squeaks. This may be coming from the cross members but I am not impressed, I will be reaching out to support to see if this can be remedied but the threat of the high return costs makes me think that RSL has no faith in their products. I am thinking that I would be better served purchasing a PB-2000. System-Yamaha 2A2, Polk ES55, ES30, ES10, SBR 75", 12S, and YU8 12"24*10 room. Remember, if you love the sound of your system then you did it right, my review is my experience and my room size.