Try a sub a third in the back

I’ll share something I stumbled upon in the off chance it transforms your listening experience as it did mine. I purchased a rel s/510 while they were on sale to replace a lesser sub. First, the sub is remarkable. I thought it would just add bass extension. I had no idea it would improve the sound stage so much. But now I had 3 subs with absolutely no space in the front of the room to place the third. I planned to sell it. If you like to tinker like me with your system, you probably would have had the same thought I finally did: connect the third sub for the hell of it. In part, the idea was inspired by the long and very good article someone on here linked to about subs: that talks about putting a sub at the back of the room for HT. The lower the frequency, the more non directional the sound. So, having a sub behind me should be okay in a two-speaker setup. The worst that might happen, I thought was that I might shake my house off it’s foundation. But what happened was absolutely unexpected. The sound in the room became amazingly three dimensional. This is not hyperbole. I have a good system and especially with the new Rel sub, there was good width, height, and depth to the sound. But the effect of adding the third sub was to double or triple the depth into the room. I didn’t believe it so I turned the rear sub on and off, repeating the songs. I’ve done this for a week because sometimes new experiences don’t hold up over time—a product of wishful thinking. This one has lasted. I will describe the change this way. Without the rear sub, the vocals were centered, other instruments were placed around the front of the room—some further away than others. Adding the rear sub stretched the centered voice in front of me from 2d to 3D, like someone was in the room, or better, I was in the vocalist’s room. Imagine taking a photo of the singer and stretching it into a 3-dimensional figure in front of you. It’s like that. Although my previous system had good depth before, with the third sub it sounded like I was swimming in the music. there was an exceptional separation of the instruments around and over me not just in front of me. I won’t go on because results will vary. But if you like to tinker and you have a third sub in the house, give it a go. I hope it turns out as holographically for you as it did for me. (Details: I connected the Rel using the line in from my power amp and two RCA outs on my Dac (it also has XLR outs that I use) to connect the other subs.)


The way I connected 3 subs was by taking advantage of the Rel being connected to the speaker outs on my power amp and the other subs being connected to the rca outs on my dac. My dac also has XLR outs that I run to my power amp. I did run both speaker channels to my rel. I’m not sure that matters. I used to run 2 subs in the front. Perhaps if I’d moved one to the back I would have had a similar 3D experience with just 2 subs. I haven’t tried that. Logically, adding a third sub would seem to just make the bass louder and smooth the bass. I can guess why the third created the holographic effect but it would be a guess. Definitely the Rel dramatically the imaging with just 2 subs. My previous subs mostly added bass extension. The high level inputs on the Rel dramatically improved the separation of the instruments in front of me. But a/b testing with the third sub in the back proved to me in my system that the 3D effect is real. Might there be an even better configuration? Probably. Might the effect be component dependent? Probably. I just thought I’d share what I stumbled upon in case you like to tinker. Bottom line, try one of your subs behind you to see if you achieve a 3D effect. I hope you do.

Im using a single velodyne hgs-10 sub directly behind me, 180 degrees out of phase.  My speakers are magenpan lrs running full range of a Kinki Studio.  It sounds fantastic!  

After reading this post and thinking huuuum, sounds like I might try this as I'm running 2 Rels in stereo up  front ..I picked up the phone and called Rel service technical support....I read him the post etc and asked if they knew of this or heard of doing this for 2 channel systems...I got a bad idea,a very bad idea along with 10 minutes of why and that stacking upfront is really the only way I should approach this.On the positive side for me ,I save money not buying a 3rd sub,lol

Funny about the advice from Rel. I respect them, love their products, and suspect they were not just trying to upsell you to a swarm. Most of us here don’t have the luxury of trying things out for free. So, we read articles, ask for advice here and when enough evidence piles up we spend thousands for things we may have not heard. So, I entirely understand the comments about consulting Rel or looking at graphs… trying to understand in the abstract because many of us can’t easily/cheaply audition components in our homes. If I could invite you to my house I would so you could hear. I can’t so my opening entry in this thread is another piece of abstract advice: some guy you don’t know claims he had a transformative experience— a person who has little credibility compared to folks at Rel. I get it. And I can’t promise that any 3 subs plus any 2 mains will yield the same result. I can only say it happened in my system and might In yours if you try. Would I spend thousands to buy a new sub in the hope of achieving a holographic sound? No. The results are too system dependent. But if you have a third sub, try it out because you know for a fact that for one person something special happened.

Fun/long article about subs sited by another agon member: