4 Velodyne HGS-15's or 2 Velodyne HGS-18's?

Your all going to get internal bleeding lol

LOL NICE ONE

The OP's question was asked over 10 yeard ago.

Just get one or two SVS PB13 Ultras with an AS-EQ1 and be done for good.....

for sure the 1812 not easy to acquire.
I went thru DD-15's X2 then tried Jl-F-113's X4(two for music and two for HT).
No matter using ARO or sub in seat position or any floor position the JL's didn't give me THAT sound.
Enter the 1812,I first heard one at a dealers room which was at least 3X my room size(12X19X7).
The demo disc was Jeff Beck(Live at Ronnie Scott's).
In a nut shell that was the best bottom end I had ever heard.
the dealer gave me a copy of that disc to try at home with the JL's,well I did try it and it sucked big time,talk about depressing.
Went to the dealer and told him it was probably his big room that made the difference,his reply is it doesn't matter the size of the room(HE WAS RIGHT)He brought the 1812 over to my house and we played that disc.
All I could say when the first few notes played was THAT's IT.
The 1812 hasn't left my room as it has the most musical and authoritative bottom end I have heard and she's superb for music and movies.The sub really opens up the mids and highs.
Sold the JL's(YES)and I couldn't be happier.
Never would have thought this sub does it all and made the JL's sound like boom boxes on the bottom end.
Down side of the 1812,heavy,large,price(if you can get one)are around 4999.00,but it's what she does for the music and I'm overwhelmed with joy what this sub does.

How about a used 1812? Not easily available, but can really shake the house.

If you're using Audyssey (or similar DRC) to smooth FR in the bass, then a pair of 18s probably makes more sense. I believe that you'll have pretty similar clean SPL capability all the way down well below 20hz from either set-up, and 2 giant boys are probably cheaper and easier to place than 4 big boys. As you note, it's probably overkill in either case (unless you got yourself one very big HT room), so there's little chance of going wrong, either way.

If you're not digitally correcting for the room, then 4 subs will probably get you smoother response. In that case, you might want to place the "top" sub on a support that's placed closer to the ceiling rather than stacked on the "bottom" sub. I'd think that this placement would take the ceiling reflections out of play (to a degree) and this should get smoother FR in the bass.

Marty

I think 8 HGS-12's sound best

4 velos.

A lot whould depend on the volume of the room/space being driven. However, It's my experience that you're NOT LIKELY to have "too much woofer", as long as you correctly match volume(s) with the main speakers.
For the record, most people have the subwoofers overpowering the main speaker(or mid/treble). But that said, often, there is not enough sub in SOME systems, or larger rooms, to properly handle the demanding bass dubties!
However, a lot depends on what volume levels you listen too. So for instance, it's possible you never push the volume level up much at all. Thus, some people can get away with a single, or marginal subwoofer situation.
In your case however, this will not likely be your concern.
It's been my expience(and I've had a lot), that you can potentially smooth out your bass in the room with a couple of woofers next to eachother in a room, and thus smoothing out some bass modes. So, 2 stacked, or 2 side-by-side. Each room is different, and results will varry.
If it were me, I would usually go with 2 stacked 15's on each side(4 total), over 2 18's. Experimentation and strong consideration of all the location options is recommended.
I would however avoid the often recommended "corner placement", as that ALWAYS LEADS to a "less than accurate" bass pressentation! YOur sound will be boomy, and "one-notey" in the bass, and you'll get "bombastic" sound even with instruments covering those frequencies covered by the woofers!...NOT NATURAL, OR WHAT WAS RECORDED!!!
The only time I'd place woofers in the corner myself, is if the sub was underpowered for the room, and needed some bass reinforcment that a corner placment would give. Even then, I'd be doing some SERIOUS EQ'ING of the woofer! So it is workable, but not as ideal. And in your case, you'll probably have more than enough woofers I suspect, so it shouldn't be an issue for corner placment.
Someone else in these posts also mentioned the Earthquake woofers. I must concur that the Earthquakes make stronger HT woofers with more "bight" and "weight" to the sound!
The Velo's are good in my oppinion for HT, but if I had to choose, I'd go with the Earthquakes in that regard I think....IMO.
Good Luck

Get a Earthquake Supernova MK-IV 15 or a pair and get ready to be stunned.

I had a Velodyne HGS-18 and thought it was the best sub for a HT/music combo. I happened across a deal on a Earthquake Supernova MK-IV 12 at a divorce sale for only $400 so I picked it up.

WOW!!!!! It was so much better than my Velodyne that I placed the HGS-18 up for sale a week later.

The Supernova 12 is just stunning in it's shear power that it makes some movies scary. It is not as good as a REL for music but just as good as the Velo.

I finally feel vindicated by the glowing review from Stereophile GTHT. No one ever believed me when I said that this sub is better than the HGS-18 until they heard it themselves.

The Supernova MKIV 15 is better than the 12 I have but I don't think my house could take anymore pounding.

I do like the idea of using a pair of subs since the room I have responds much better. I used to use 2 subs for left and right and the Velo HGS-18 for the center/surrounds/LFE but since adding the Earthquake I only use it and a old Kinergetics research sub which is hidden under the coffee table in the center of the room.

The Earthquake Supernova subs are the real deal and you would be making a mistake if you don't compare it to the HGS-18. I am sure you'll be a convert too and save a lot of money to boot.

Get the 18's and put them in corners (or close to.. if you cant tame them) and make sure your homeowners ins covers
structual damage from non-natural sources.

I wouldn't stack the 15's and I would suggest putting the subs outside the main speakers. Almost no manufacturer reccommends the inside the main setup. If you want four subs put them in four corners. The Velodyne 18's are great so use em. I personally have two Revel sub-15s and they fantastic both for music and HT. In the scene in Matrix where the helicoter hits the building these things are bone jarring.

I'm using 3 HGS-18s across the front of my main theatre. I tried the 15s as well. I highly recommend the 18s over the 15s for a more literally 'stunning' result. Was using M&K 5000s and 350s. The 350s are on the sides and rear channels now and the 5000s are in the master bedroom system. Room tuning/treatment became more critical with the larger driver Velodynes than the M&K dual 12" design.
DrM

Curt -

I used to have a pair of HGS-18s and loved them. Went to a pair of Aerial SW-12, but heading back to Velodyne! The 18s are great, was just curious about the 4 15's.

Jmcgrogan2 -

Funny enough, 4 HGS-8 is an option! Ridiculous, but an option!!

D

Good way to rid the house of rodents and cockroaches. I have a Mirage with (2) 12 inch drivers that shakes my house, but hey, I get more if I could. Overkill is the way to go. I'd get the 2 HGS-18's. Is 4 HGS-18's an option?

I use a pair of HGS 18's and that's what I would suggest. The HGS 18 sounds (and tests) better than any sub I know of and I've heard and tried most of whats out there. The stacked 15's might be about as good, but would not be any better.
Good luck,
Curt