Single REL T/9x vs S/510 in Small Room

Currently I have a PMC TLE1 sub in the main system. It sounds rather decent when matched to the main speakers. The integration is quite seamless. I’m not sure if a higher grade sub will bring more to the table.

Question. Has anyone experienced a noticeable or staggering difference when swapping different grade of subs in a small room, as in a one to one swap. Not single to dual sub swaps.

The next question. Is there a noticeable difference between the REL T/9X and S/510 when used in a small room of say 10’ x 17’. Or any other sub comparison for that matter.

Any thoughts would be appreciated.


My room is a bit bigger 19x15 w 10' ceilings..I run (3) sounds fantastic to me...I went from one T7i  to one S510  intially and it was eye opening...adding the second was a transformation...the 3rd behind was not so much and sometimes I don't even have it running..but IMO since the s510 has increased several hundred since my purchase last year I'd go with the T9x and bank the difference. 

Thanks for the post. 15 x 19 is quite large. Hence it is not a surprise that 3 subs work better than 1. Yes, the S510 costs considerably more than the T9x. Just unsure if there will be a noticeable difference if doing a one to one swap ie. from the PMC to REL T9x / S510.

Will decide and take the plunge when ready. The system sounds fine as is.



There is a pretty significant difference between the two. The 510 is just “bigger” I’ve had both, kept the S510. The T9 does a pretty good job. I’m stuck with the reality of only having one sub floor space wise. My next move is either an S212 or another S510 stacked. As mentioned, two T9s would be excellent as well. But, if your option is just one do the 510.

I have a lot of REL including 6#25 and 2 510, and for a small room you need DSP, at the very least continuous phase adjustment

i would look for something more flexible than REL

Just to wrap things up. Settled with a single S510 and this thing blew the PMC sub out of the water. No joke. I did not try other subs but this REL is quality. Recommended.



@ryder Awesome choice!!! Last year I had a single T9i in my main system and wanted to add another T9i. I bought a used one and it was amazing. I then got a great deal on an S/510 and let me tell you even a single 510 blew the T9i pair out of the water. It's just a different beast altogether. While the T9i has great bass, the 510 delivers that gut punch but with surprising grace and finesse. Since then, I've added one more 510 to my system and couldn't be happier. 

Thanks Arafiq. That’s good to know. It’s a single S510 for me unfortunately since I don’t have the space and funds for a second one. I’m sure 2 will be better but I’m very pleased with the performance of the single REL so far, no complaints

I have two s/510’s and spent the time fine tuning through the high level connection per REL’s philosophy once dialed in (it will take time) it was the most significant bang for buck upgrade I have ever made to my system.  Once you have the speakers and the amplification sorted this should be the next investment.  Don’t wasted thousands on power conditioners, interconnects etc. once you have decent quality cables (few hundred bucks) the diminishing returns are massive use that money on a single or pair of REL’s.  Its not just base the impact on soundstage and imaging is material.

I’m not going to suggest REL make the only good subs but I will say don’t buy subs off speaker co’s just like you wouldn’t buy speakers off a company that specializes in subs.  A sub is a different animal and different type of speaker that requires different R&D.  Go REL, JL Audio etc.  I’m going off script here a bit but needed to get that off my chest……