one 12in sub or 2 8 inch subs

one rel r528 or 2 rel t7 with magnepans
Hey I have found that even though bass is omni directional that the soundstage presence is improved if the bottom end is as balanced as the mids and high frequencies.
Not to steal your thunder but I am currently running 2-8" self powered subs on both left and right channels. 2- left 2-right. 200w each side and adjustable.
I find the sound stage to be more appealing but YOUR ears are the final decision makers.
Hope this helps.
I'm using 2 M&K KX10 powered subs (one one each side) with Lipinski L707's and the sub and monitor sound as they are one speaker. I run the subs just to the outside of the monitors. You also have the option of 1,2, or no sub.
thanks for your response . that is what i suspected . with 2 subs is it less likely to over drive the smaller 8 inch sub .with just one 8 sometimes i feel i am on the edge with it with high volume music
I suspect 2 is better than one.
Spreading out the low frequency sources also helps smooth the room response.
The biggest obstacle to natural-sounding bass is the room. Seriously. The room imposes an inevitable, and drastic, peak-and-dip pattern on a subwoofer's output. The peaks and dips are too far apart for the ear's natural averaging-out characteristic to come into play, and moving the sub or the listening position only re-arranges the peaks and dips - it cannot eliminate them. EQ can eliminate the peaks and dips at one location, but will make them worse at other locations.

No matter how smooth your sub's response starts out, by the time you hear it, the room's effect is in full cry. You see, the ear has to hear more than one wavelength of a bass tone before it can detect the pitch. Think of how long bass wavelengths are, and how big your room's dimensions are, and you'll see that by the time you can hear the pitch of a bass note, the energy has already bounced around the room multiple times. You literally cannot hear the sub apart from the room. Sub + room = a system.

Now if you have two subs spread apart an appreciable distance, their in-room peak-and-dip patterns will be significantly different, and these two dissimilar patterns will tend to average one another out. And they will produce a net peak-and-dip pattern that has its peaks and dips closer together, so that the ear's natural averaging mechanism will reduce their subjective impact somewhat.

Generalizing a bit, two subs spread apart will give you twice the in-room smoothness (and half the average variation from one location in the room to another) as a single sub. And four subs will be twice as smooth as two. Todd Welti and Earl Geddes are proponents of multisub systems, Welti focusing more on symmetrical placement while Geddes focuses more on asymmetrical placement.

While a single 12" ubersub will go deeper (and probably louder) than two 8" subs, the pair of subs will do a better job of working with, rather than against, your room's acoustics.

Imo, ime, ymmv, etc.

very helpful thank you to all who responded !!!!!
In general, I'd always say that two is better than one. And (see below) four may be better than two.

There are many excellent 12" subs out there for which a pair costs less than a single r 528. Both Rythmik (my choice) and SVS (highly regarded by many) offer a pair of 12" subs that will outperform the Rel on the test bench (not necessarily the same as sounding better). In each case, a pair sells for under $1500/pr. IIRC, the SVS is closer to $1100.

Duke, who posted above, owns Audiokinesis, which sells the Swarm bass system with four 8" subs for $2500. That might be one more good option to consider.

Lots of people love Rel, but I question the value proposition. Not trashing the brand - numbers never tell the whole story and personal preference varies - just suggesting that you might wish to explore some alternatives that offer more measured performance for less $.

As always, YMMV.

neither, choose at least 15 inch. Subwooder need to be closed, no bass port. Rel is in Europe not that popular anymore. Many Rel sub's I tested are sooo slow. Even wenn people would give me extra free money every day by receiving a free Rel I would not want them in my house.
8", and even 10" sealed subs will roll off fairly high unless equalized or some sort of servo feedback is employed. Ported or passive radiator designs will give extra bass extension at the cost of larger cabinets and reduced transient response. If the subs are expected to play higher frequencies,say 100 Hz, that transient response becomes more apparent. Below a certain point, it's more just "rumble", not that that's a bad thing.

I agree with Duke but there are limitations of smaller sub drivers that can be reduced partially with multiples. That said, I'll be starting work on dual 10" subs soon.
Two is better than one in every way, especially if power is doubled with two as well.
Hey just curious... Which other speakers are you runnin with the sub.
That will probably help you decide as well. Just an after thought.

03-17-13: 2012chipmunk57
Hey just curious... Which other speakers are you runnin with the sub.
That will probably help you decide as well. Just an after thought.

I agree; it should have been the first thought, not an afterthought. If you're matching sub(s) to small stand-mount speakers with 4 or 5" woofers, dual 8" woofers would be a better match, both for speed and dispersion. If you have near full-range floor standers with dual 8" woofers or a 10", then you'd want one or two 12" or even 15" subs.

I have a pair of small floorstanders that use 5.25" woofers. They don't produce much meaningful bass below 50 Hz, especially in my living room which is open to the rest of the house. I augment the bottom with two 8" powered subs. They're sealed, but have dual passive radiators. There's still not much bass below 35Hz, but they provide extension to cover bass guitar, tympani, concert bass drum, etc. The best part is that these subs are very quick and blend seamlessly with the mains' 5.25" woofers.

Two 8" subs have almost the same radiating area as a single 12", but the 12" will reach lower but may well have a slower transient response owing to the larger diaphragm. However, if you look at the driver designs of JL and SVS, they appear to have the magnet strength and structural rigidity to have excellent transient response.

So really, the answer to the OP's question depends on the frequency range and output of the stereo speakers relative to the size of the room, and which part of the low frequency range you want to augment.

Take a look at SVS Sound's dual subwoofer packages. One or more could fit your needs and budget. They have a dual 12" pkg in sealed enclosures that's below your budget and a dual 12" triple-ported design that's right around your budget. The cool thing about their triple-ported design is that they include three port plugs so you can choose from four different bass alignments for damping and room-matching. Instead of either-or, here's a source for dual fast 12" subs that would fit your budget.

Disclaimer: I have no affiliation with SVS or any other sub maker or dealer. I have an audiobuddy who has an SVS sub mated with his Magnepans and that's the extent of my personal experience with that brand. I personally own 5 Mirage subs and have a matching pair of Mirage MM8s augmenting a pair of Mirage OMD-15s.
I'd personally go with a pair of svs sb12 nsd's. I had an svs sb12 plus which was the predesessor to the sb12 nsd and it was a great sub. I would have kept it but the color didn't match the rest of my gear, and I was having a hard time finding another one (I wanted two because two gives a more uniform sound with more headroom). So anyways, I sold it and when I'm in the market for subs again, I'll probably get a pair of the svs sb12 plus'. I remember seeing awhile back that they had a slight discount if you bought a pair; might be worthwhile to ask them. All in all, my svs played pretty low (22 hz?) and was pretty fast and the new sb12 nsd is supposed to be even faster with less overhang. I don't think you'd be disappointed in any way with a pair.
Ya know this doesn't have to be as confusing as people tend to make it. Do as Duke suggested and understand what he's saying. Not that you don't know but just in case. And your chances of success will greatly improve.

I have no afiliation with Duke and have never met him, but he's got this subject covered as well as I could have said it.
Good luck
An old rule of thumb;

(2) 8in subs are equivalent to (1) 12in sub.

(2) 10in subs are equivalent to (1) 15 in sub.

With either double 8 or 10 inch subs, the bass is much more refined vs. a single, larger driver IMO.

Additionally, the larger , single driver requires more air pressure to be moved, for better sound.

Happy Listening!