Subwoofer Rec for Home Theater

Greetings HT buffs! May I pick your brains? Recently bought a home, and to my surprise there were speakers already in the ceiling, as well as a passive subwoofer in the wall (below "R. Surr." in diagram, near floor). Over the past couple months I crafted a strategy to improve upon this room (rewire to 14 gauge wire, move two of the ceiling speakers to the back of the room for a total of 6 atmos, and add some on-wall speakers for sides/rears).

Opening up the subwoofer to check it out, I discovered it is passive, and has L/R +/- (4) inputs and the same number of outputs. Wires were running back up to the fronts (presumably lows filtered out, staying at the sub). It is my understanding that this type of filtering is pointless now, as the AVR will do it. Plus it's more connections and extra cabling. The diagram for the room is attached.

Is it reasonable to use the existing passive sub with a single cable (+/-) running to it? Will my Denon even work with a passive sub (I only see Subwoofer labels in the pre-out section)? Should I be taking that passive sub out of the wall, patching the drywall, and buying an active sub or two and placing them elsewhere in the room? If I have to run cable for the sub (is wireless an option?) I need to figure that out now, as the handymen are here the next couple of days and I didn't anticipate this complication.

Thank you for any help or advice!

Credit Crunch

Equipment: Denon 8500HA, Elan ME650C (6x ceiling speakers existing, for Atmos, and I figure even 15 year old speakers will be fine for this), Elan MP800S (passive sub), and then a suite of 7 Dali Oberons for the main speakers.


IMG_0105.jpg
 
All's well that ends well. The old passive sub came out of the wall and it's patched up. Ordered two Denon wireless subs, even if there are some haters for it being 8". Figure it'll be a breeze with HEOS and make most use of receiver. Thanks for all the good reads.
 
D

Deleted member 901590

Guest
Thanks for all the good reads.

Your post hadn't been here that long :)

It may be too late for you to cancel but, you seem lucky enough (by your current equipment and what you've ordered) to have a good amount of money. I would strongly suggest that you get better subwoofers.

The haters aren't because they are 8" specifically, the haters probably mean that better subs with a higher output and a lower extension would really make a lot more of you system.

An x8500HA in 7.x.6 deserves, in my opinion, at least two beauty subs.
 
Totally open to better solutions. It's unlikely I'll be running cables, so it'd have to be wireless, and I'd prefer not to need a dongle or interconnect to the receiver. I figured that meant the HEOS solution would be simplest. Until yesterday I had not researched subs. Big fan of "don't let the perfect be the enemy of the good."

The receiver was sort of happenstance. I had been planning a few models down, but had a realization that there were already 6 ceiling speakers. So I moved a couple around and figured why not go .6? Then I realized I could put in sides even if they are about 3 feet forward from the listening position (maybe they should be wides?). The rears are bout a foot off the ceiling. The center is probably too low. Suddenly there were 13 channels, despite a few compromises. The 8500 was the only solution, and is the finest electronic item I've ever enjoyed. My last Denon served from 2003 to 2022, and still bumps in the garage.
 

Gasp3621

Distinguished Member
You going to need few of these type of small boxes if you go wireless. Then you can start looking real subwoofers. Better to cancel the Denon wireless sub order if you feel you can live with these adaptors.





What is your budget for the subwoofer (one larger / two smaller?) and the room dimensions?

You have bought Dali Oberon 7, Oberon Vokal etc. speakers already?
 
D

Deleted member 901590

Guest
Totally open to better solutions. It's unlikely I'll be running cables, so it'd have to be wireless, and I'd prefer not to need a dongle or interconnect to the receiver.

Well, there are wireless solutions but I'm not aware of any that wouldn't at least require a dongle at the AVR end. Hopefully someone else may comment on that.

Until yesterday I had not researched subs. Big fan of "don't let the perfect be the enemy of the good."

I get what you're saying. But, in my world (and many others' worlds), the subwoofer/s is/are one of the most important parts of the immersive nature of film and TV. If I was building a system gradually from the start today, starting at 2.0.0 my next move before any other speakers would be 2.2.0 - that's how important decent subwoofers are to me. :)
 
What is your budget for the subwoofer (one larger / two smaller?) and the room dimensions?

You have bought Dali Oberon 7, Oberon Vokal etc. speakers already?
The room is 28' x 14' or so. Already bought the Dalis, as they seemed to have a good value and won a few awards. Been enjoying them in stereo for several weeks. Two subwoofers was the plan, since the Denon can drive them both and better sound in that fairly sizeable room. Budget somewhat flexible--even a rug is $500, and this house doesn't fill up itself.
 
Well, Denon's reps are saying that the wireless sub won't work with the x8500. That blows my mind that it wouldn't but I guess I'll be having to look for other options, including reevaluating whether to run long cables.
 

Gasp3621

Distinguished Member
Well, Denon's reps are saying that the wireless sub won't work with the x8500. That blows my mind that it wouldn't but I guess I'll be having to look for other options, including reevaluating whether to run long cables.
Yes no suprise as the wireless rears doesn´t work with X8500HA either, it requires the specific Denon Heos receiver. X8500HA is a flagship receiver which can power some very expensive system in a large room. You went really all in. Do you live in US as you mentioned $?

Can you place the two subs where they work best or does wife have a saying? Just thinking are you better to go with one sub cause it´s quite pointless to spend big bucks if they go how wife says (looks best). You have space on inside of the right oberon 7 main speaker so between that and center channel is probably first option. The 2nd sub would most likely be best at the rear wall diagonally opposite side to that front right so rear left. With this type of narrow and long room depending where you sit it can give very smooth response.

Do you have some size restrictions, finish preferences etc? To give you rough idea what many of use would think as great starting point for this type of room see link below and also comment what you think (finish, size, price etc).

 
Do you have some size restrictions, finish preferences etc? To give you rough idea what many of use would think as great starting point for this type of room see link below and also comment what you think (finish, size, price etc).
Hi Gasp3621, thanks for the input. Yes, I live in the US. Wife is already on board with what's in there, so she'll be down for another couple of sub boxes. The rest of the speakers are white, but these little boxes I don't care too much what they look like. The top/right part of the room you mentioned could work okay. There is a lot of space between the couch and the front wall, although there is a fireplace there so it would have to go closer to the right wall or the couch. Good to know about the diagonal placement. I saw the Monoprice thread earlier today. Will keep shopping!
 
So Dali makes a 14" around $1700. The Monoprice 13" is about the same. There is a Monoprice 12" THX Ultra for $800. Do you think I could get away with dual 12" in a 28x14x10 room (and it opens up on one side quite a lot to other rooms)? I try not to pinch pennies but that's a big difference going from $800 to $1600. The Monoliths really are monoliths. Huge. I'm not sure I can sneak in a 2nd one across the room's corner. Even the first one may as well be a coffee table.
 

Gasp3621

Distinguished Member
So Dali makes a 14" around $1700. The Monoprice 13" is about the same. There is a Monoprice 12" THX Ultra for $800. Do you think I could get away with dual 12" in a 28x14x10 room (and it opens up on one side quite a lot to other rooms)? I try not to pinch pennies but that's a big difference going from $800 to $1600. The Monoliths really are monoliths. Huge. I'm not sure I can sneak in a 2nd one across the room's corner. Even the first one may as well be a coffee table.

I would play it safer as the placement can make such big difference. So basically choose something that gives you more options placement wise.

One fine pick at 1500$ (dual deal) would be SVS PB1000 Pro. It`s slightly smaller, but packs really good performance still and as you live in US you got all the goodies with the company, read the 2nd link. So basically it´s risk free purchase with the long home trial period with free shipping/return plus also if you start to crave more you have 1year upgrade programme which let`s you swap them for something larger (never say never with this hobby!!) and you also got the best customer service/support what we have seen with SVS over the years.



One perhaps wilder idea if you are still open for spending bit more (2100$) would be to consider the cylinder 2x PC2000 Pro. They doesn`t take much floorspace, but they also look "special" so need to have talk with wife surely. If intrested check youtube videos for better idea of the size/looks.


Forget the Dali subs. High tuned ported subs with eye watering prices.
 
Love to hear further thoughts about these fantasies soon to be manifest.
  • Subwoofers are often around 100lb. Is it reasonable to rest one inside the built-in cabinet about to be built? The bottom portion of the cabinet design is about to be redone anyway, as the center speaker is better on the far right of the cabinet (to put it in the middle of the room). It would be easy to leave the left portion of the cabinet as a large open square, and buy a subwoofer with the driver facing out. This cabinet is fixed to the studs and the sub would be on the bottommost pedestal a few inches off the concrete floor. One sales rep worried that the sub might vibrate the cabinet, but physics suggests that unless it is creating a tornado in the cabinet, the 100 pound unit ought to be unaffected by no-matter-what comes out the driver. It would be a design fail otherwise. People use their tops for drinks, no? One clear downside of this is that the position of one unit is thus fixed and may be suboptimal. It is, however, a corner. And the only feasible diagonal if we are going to do a diagonal. A difficult-to-assess risk is where it would plug in, if there. The wattage makes me think twice about plugging it into the Furman PFi15, but maybe it would be fine? It could go into the other wall socket there no problem, but probably those two sockets are on the same circuit. Upsides are good use of cabinet space, no need to run cable, hidden bulk, hidden cables. There are many cubed units fitting in a two-foot-deep cabinet. Will get the cabinet-maker's opinion too.
  • Is it okay for the center to be recessed in the cabinet 3 feet deeper than the fronts, which are obviously in front of the wall? The receiver/Audyessy makes that one louder, right? Seeing its distance estimates was fun. The plan had always been to put the center in the built-in. But sitting in the room now, seeing things come together, it is also feasible to put it on a small pedestal in line with the fronts. Ain't nobody got any reason to be going up there.
  • SVS suggested 2xSB4000. This cube style would fit well.
  • Both subs up front vs diagonal? Is this just a test and see? Between the couch and the right speaker is a lot of space, where a second could go easily, and the cable lay would be easy using the existing wall run serving the right front. Running another cable to the diagonal is possible but some hours of labor and more paint/patching/drilling.
 
Went with the SB4000s, found a discounted pair and changed the cabinet design to place one in the bottom left (and moved the center channel to the far right). Going to try the second sub somewhere by the front-right speaker and hope for the best. Found several examples of people who had made their sub built-in with no issues, especially with this kind of sealed sub. Cables ordered. Awesome! Thank you to all.
 

Gasp3621

Distinguished Member
Good to hear you got nice deal! You going to need some tweaking after running Audussey (do 3mic positions in fairly tight area 30-60cm), get back to us if you need help setup wise. Placing sealed sub inside the av-unit isn`t issue if there is no bottom part and it´s sturdy otherwise.

Edit. The picture is from AVF advertisers own house

IMG_7232-e1494861679887.jpg


Don`t hide the center channel if possible. Raise it close to seated ear height as possible, mount tv on wall or buy floor tv stand to get it higher. Center channel is most active speaker in your system. Hiding it inside unit can colour the sound and too low shooting knees is not ideal either leading person accusing the speaker sounding poor. Long story short, give it some thought and try to optimize things as well as you can.

Keep us posted how it sounds and remember there is few things you need to check after Audussey run from Denon menu: subwoofer levels below -12db for each sub, speaker size all small, speaker crossovers not set lower than 80hz, subwoofer mode LFE..
 
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Awesome cabinets, Gasp! Don't worry, all the lower spaces for components do not have doors. Everything faces to the room with no obstruction. The center (and the sub) are just 3 feet further back (because they are in the wall niche). Will follow up when it's all set up. Thanks for the confidence and help.
 

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