18 inch subwoofer vs multiple 12 inch subwoofers with bookshelf speakers


I am currently in the process of selecting a subwoofer system to complement my bookshelf speakers (3x KEF LS50 Metas with 5.25-inch midrange drivers, 2x KEF Q150) to achieve a balanced and immersive audio experience. Size of the room is (19.5x13x8).

After thorough research, I have narrowed down my options to two configurations: 1x Rythmik F18 18-inch subwoofer or 2x Rythmik F12 12-inch subwoofers, with the possibility of expanding to two F18 or four F12s in the future.

My primary criteria for the subwoofer system are musicality, speed, transient response and depth of bass response, particularly in the low-frequency extension below 18Hz. Additionally, I aim for seamless integration with my bookshelf speakers, ensuring a cohesive and satisfying soundstage for both music and movie content without overpowering the midrange and high frequencies produced by the bookshelf speakers.

I would greatly appreciate any insights or recommendations you may have regarding which configuration—either the single F18 or the dual F12s (possibly 2x F18 vs 4x F12) would offer better synergy with my bookshelf speakers and deliver a fuller, deeper sound with smooth and fast transient response across frequencies with 50/50 music and movie?

thxbest

I used to have 1 REL sub, tried 2 Rythmiks F12 and preferred the latter, then added 2 additional F12 for a nice improvement, then added a miniDSP 4x10HD and Multi Sub Optimizer (MSO) for an even better result. Very much in line with above posts.

Multiple subs.allow for smoother frequency response across morecseats in the room. MSO enables a flat response across several seats. It does require a measuring mic, though.

One suggestion is to consider two Rythmik F8 under/very close to your LS50. F8 can be crossed much higher (up to 250Hz but you don't need that much). You could run F8 say 20 to 150Hz and two F12 from 20 to 60Hz.

I had my Rythmiks for about 12 years without issues. And the same folks keep replying my questions at Rythmik, which is nice.

ditusa,

The article by Doug Blackburn is absolutely correct. The "speed" heard is not from the bass. It is from the accurate reproduction of midrange and HF overtones of the bass fundamental. Smaller bass drivers extend up to the mid bass and significantly into the midrange. Most critical is the integration of the midrange and bass drivers. Larger bass drivers are good for only one thing--deep bass extension.

viber6,

So let's say a 12 inch sub for instance Rythmik F12 does perform and blend better with KEF LS 50 Metas than an Rythmik F18 sub because of the better mid bass, no matter if servo controlled or not?  

thx best,

I don't know the Rythmik products.  Servo controlled is another factor.  Theoretically, according to Doug Blackburn, I would predict a servo 12" would still integrate better than a servo 18".  But it would be an apple/orange comparison when comparing a non servo 12 with a servo 18.  

As an aside, in 1980 I heard the HQD system--double Quad 57's, Decca ribbon tweeter, 24" Hartley woofer built into the floor whose cabinet was the room below.  The Hartley was probably not servo.  Those Quad electrostatic are still unmatched for midrange accuracy, and probably for upper bass accuracy.  I don't listen to music with much deep bass, so I couldn't comment on the quality of the bass from the Hartley.  Mark Levinson, who put together the HQD, drove it with triamped Levinson ML2 power amps and used crossovers to keep the midrange overtones from the H out of the Quad midrange.