Subwoofer Choice

I am in the process of building out my system. I have the end goal in mind, and ticking off the equipment as I get them. I do need some advice in the subwoofer category.

I am currently driving Monitor Audio Silver 500s with a Michi X5 integrated amp (600w @ 4Ohms RMS). This is way overkill for these speakers. But my purchase (coming in August) will be the Focal Sopra No. 3s.

That being said, I am looking also to add a subwoofer and I’ve settled between two (2) REL T/9x’s or one (1) REL S/510. T/9X is $1,249 vs S/510 at $2,749.

There is a REL youtube video from their chief designer comparing (briefly) the two and actually stating that "just because one S/510 costs twice as much as 2 T/9x don’t think you can equate them with 2 vs 1". I paraphrased a bit.

But the below is only 3min long please watch and let me know!

What are your thoughts. Obviously 2 subs are better balanced than 1, I get that. But given the specs here am I better at buying up for the better 10"?

Listening room is carpet, 16’ x 24’. 384sqft. 8ft ceilings. What info did I leave out?



Hi bound4h...thanks for the topic.

I've spent most of my 40+ hi fi years with larger monitors and no subs in several rooms.  My Chapman T-4's dug into the 30hz region and I was always quite happy.  In the last 23 years, in my dedicated studio, I've experimented with subs and better monitors...Salk Veracitys and my present Revolution Be's...discovering subwoofers, indeed, add refinement to the ENTIRE frequency spectrum.  In the last several years, I've used a pair of Paradigm Ultracube 10" sealed subs beneath my monitors, with careful isolation.  This, in essence, created a "full range" presentation in a small space.  

Recently, one of my Paradigm subs failed.  To my great surprise, using ONE subwoofer increased the quality of my sound, to all parameters!  Since the surviving sub is also showing sign of failing, so I've been doing a deeper dive about subwoofers in small rooms.  A friend, with equivalent experience, said ODD numbered subs work better in small rooms.  I've researched "swarms" of subs, but that's simply too complicated in this small space.  

Jeff, my long-time audio Tech friend who has much experience both building and helping others with subwoofers has recommended the Rythmic L12 Direct Servo subwoofer.  "Speed" in the context of subwoofers for music vs HT, is a topic worth researching, relative to start and stop timing and decay.  A "direct servo" addresses that for music.  Jeff also prefers larger drivers working less and quicker. 


I also have a preference for the musicality of "paper cone" drivers, so the Rythmic L12 is on order and on its way to me.  This will mean a change-over to conventional loudspeaker monitor stands and finding the sweet-spot for a single subwoofer, in my studio.     HUZZAH!     After all these years, I continue to be excited and recharged by chasing better sound.  Like springtime, everything gets refreshened.  Will report back further down the road.  

(bold print for old eyes)      More Peace.       Pin

May I suggest Monoprice's Monolith Subwoofers!   They come in all different sizes and price ranges and they're top of the line can often be caught on sale.  Besides being very reasonably priced their quality is top notch which you can read all about them in many reviews.  I personally just purchased their 2,000 Watt Dual 15" Subwoofer which although I still haven't or hooked up because I have pneumonia keeping me down, I've done my all my research and am quite satisfied with their Customer Service and my prior interactions and inquiries.  


Great post, pinthrift. Looking forward to your impressions. I bet it’s going to be fantastic.




I put together a system for my daughter that has the Monitor Audio Gold 50 and Rel  Tx9.  They mated well together


it does not look like the Michi will support the CR-1 crossover. You would need an amp input. Does the michi have bass management built in? Looks like it has a sub out.