Subwoofer Class A/B vs D Power Amplifier

Dear @vta2005 : First than all the units you named are not subwoofers so the amplifier is not an important issue.

The Rel goes down to 32hz at -6db and this means that probably you can't get bass at no lower bass range of 45hz.

The JL is alittle better on that regards with a spec of -3 db at 29hz but no one is a subwoofer.
 A subwoofer must goes down below 20hz, not at 20hz as many of us could thing.

So, look at JL other model and don't be to worried about the amp design when is more important the subwoofer overall design and its quality levelexcecution of that design.
No, you don't need 3-4 subs in your room. As a fact no one needs it in a home system to listen MUSIC no matters what.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

I have absolutly no doubt, within the first ten seconds your choice will be obvious. The only difficulty may be finding a dealer who carries both brands. 

The REL T5 is great for a small room. They are so good and blend so well that you don’t need to use 4 of them. One is fine, two is better, but it depends on your music.

The JL will likely overwhelm a small room.

I like to keep amp classes both Class AB, but that is a personal preference, similar to how I like paper cones more than aluminum cones. 

erik 1+

I don't think a dual sub is needed, and not what the OP is asking about.


OP: I wouldn't worry about the class of amp. I'd worry a lot more about room correction. JL has one of the best.

Erik

I concur with Millercarbon.
Using at least a pair of subs is the way to go.
I know Audiokinesis has a Swarm system that is supposed to be a killer.
For me, I use a pair of Vandersteen subs, which use a high pass filter to help seamlessly integrate them with the speakers.
Class D amps are relatively inexpensive to build compared to Class A or AB. Considering they will be only powering lower frequencies, I would say it shouldn't make much difference sound-wise, but, I may be mistaken.
Perhaps Ralph of Atma-Sphere could chime in....
Bob

I don’t think it’s any big deal using a class D amp with a subwoofer. I use the JL Audio D110 and I think it is outstanding. I have never owned a REL so I can’t give you an opinion on it. But I can say that the JL is better than other subs that I have owned!

Not that there aren't differences, but whatever difference there is pales in comparison with the difference between using just one and using three or four. Whatever the budget, you'll get better results using it to buy four than putting it all into one. Search Swarm, distributed bass array, read and learn what I'm talking about.