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Kevio
12-20-2008, 02:49 PM
I've never owned a sub woofer and lately it occurs to me that I might be missing out on something. In stereo, sub woofer systems I've listened to give me the distinct impression that the bass is coming from the sub woofer and it doesn't feel integrated with the music coming out of the mains. And so I've avoided them. I'm willing to believe that that won't be so much of a problem for me in the context of a home theater.

I set up a home theater a few years back and never got around to attaching a sub woofer. It is probably time. I have a Sony surround receiver about 100W/ch and Infinity Entra Ones in the front and Infinity Primus PC250BK for the center, Minimus 7's for the surround. I've told the receiver I have large speakers in the front so I get a fair amount of bass and plenty of loudness from the system.

How much will adding a sub woofer improve things? Any advice on placement and what to buy? What should I tell my kids when the rumbling keeps them up at night?

N. Abstentia
12-20-2008, 07:30 PM
If you don't have a subwoofer you don't have a home theater :)

It's kind of like driving a Ferarri but never leaving 1st gear.

blackraven
12-20-2008, 07:59 PM
Get a sub, you are missing out on a lot of effects in action movies. When your kids are sleeping, turn off the sub. For 2ch stereo, many people have the sub set way too loud and may have the cross over set wrong or wrong placement . But your right, in 2ch a sub may not integrate well. When I use to use my sub with my MMG's, I set the sub so you could barely hear it and then 1 notch lower. It added a much needed fullness to the sound.

Kevio
12-21-2008, 01:03 PM
What should I be looking for in terms of specs and brands? A $99 Energy sub was mentioned on a recent thread (http://forums.audioreview.com/showthread.php?t=28352). How much power do I need? My room is 20' x 12'.

I agree that subs out in the wild are almost set way too loud. That's probably (an unfair) part of my objection to them.

blackraven
12-21-2008, 05:11 PM
That energy sub would work but I would consider the Mirage Omni S8 or the new Mirage Prestige S8 which has twice the power. http://www.vanns.com/shop/servlet/item/features/549499255/mirage-prestige-s8?ne_ppc_id=705&ne_key_id=2755024

http://www.vanns.com/shop/servlet/item/features/549349941/mirage-omni-s8-black

zepman1
12-23-2008, 06:54 AM
I've never owned a sub woofer and lately it occurs to me that I might be missing out on something. In stereo, sub woofer systems I've listened to give me the distinct impression that the bass is coming from the sub woofer and it doesn't feel integrated with the music coming out of the mains. And so I've avoided them.

The problems you mention indicate the sub is not setup properly. I have no problem integrating it with my mains for 2Ch music, and HT is much easier. Location is important, you really have to experiment with this. Bass is non-directional when the frequency is low enough, so the lower the crossover is set, the better. Set the crossover near the lower end of your main speakers range. It helps to have a audio test disc and SPL meter to flatten out your frequency response. Finally, for music, set the sub gain as low as possible, most people set it too high. I do like it cranked up a little more for HT use though...

Adding a sub will make a huge impact and improvement to your setup for both music and movies. Consider the Outlaw LFM-1 for $399. I have one and it outperforms my similarly priced Velodyne CHT-10 (which I also think is nice). Not sure what your price range is.

fahrenheights
01-08-2009, 10:41 AM
i have a question reg. 2 ch audio w/ a sub. Right now I have have a Yamaha YST 315 sub on which has a crossover and small amp. But I'm looking into getting some better speakers and wondering if having a sub between the 2 main LR speakers and the amp affect the sound quality in any negative way?

Right now I'm looking at B&W 602s with the sub handling lower end freqs.. Would you recommend this set up or instead remove the sub and get some 603 or 604s?

Thanks in advance

Auricauricle
01-08-2009, 12:35 PM
Kevio: without knowing too much about your speakers or the material that you wish to listen to and watch, I cannot recommend or dissuade you from your decision to buy a subwoofer. Based on the speakers you use, I would think that you're not hearing "everything". If this is the case, and if you honestly discern a lacking, then maybe a subwoofer would make your day. On the other hand, if you are content with your system, then you're probably fine with what you have....

f0rge
01-08-2009, 01:17 PM
you really need a sub for HT, you're missing out there. you can turn it off for music if you dont like it.

take a look at SVS, they make wicked subs.

Kevio
01-08-2009, 08:37 PM
I don't know what my price range is but I ordered and installed the Energy ESW-8 in my HT to get my feet wet with this. My front speakers go down to 60 Hz or so and I'd rather them do the work if they're able. I set my crossover frequency at 80 Hz and played some music I'm very familiar with to adjust the subwoofer level and play with phase selection and then I turned it down just a little bit more. All sounds good and integrated now. My system now extends down an additional octave. I can't say it is strikingly impressive but I can say it is an improvement for movies. Doesn't really sound any different when listening to music or watching television.

I did discover that although the ESW-8 is billed as a 200 W subwoofer, RMS power is actually only 50 W. This may turn out to not be a powerful enough speaker for my room.

canuckle
01-10-2009, 01:19 AM
The ESW-8 is the most entry-level sub that Energy offers, it doesn't extend very deep and, as you noted, doesn't bring a lot of oomph to the table. If you replaced it with the ESW-V8, I think you'd note a big difference. But, as you also mentioned, the size of the room needs to be considered when determining the size of the subwoofer. A corner position will boost its output and extension significantly if you're able to place it there. An 80Hz crossover is exactly what it should be and your fronts should now be set to small (letting their "work" be done on the higher, less power-consuming frequencies).

If you don't have a receiver with Audyssey, YPAO, or MCACC, then you'd do well to get a test tone/pink noise disc and an SPL meter. What sounds integrated to your ear may actually be way off and your system might benefit from some more adjustment.

The good new is: you can now listen to the .1 channel which should be a very nice addition ;)

Kevio
01-10-2009, 08:51 AM
The ESW-8 is the most entry-level sub that Energy offers, it doesn't extend very deep and, as you noted, doesn't bring a lot of oomph to the table. If you replaced it with the ESW-V8, I think you'd note a big difference. But, as you also mentioned, the size of the room needs to be considered when determining the size of the subwoofer. A corner position will boost its output and extension significantly if you're able to place it there. An 80Hz crossover is exactly what it should be and your fronts should now be set to small (letting their "work" be done on the higher, less power-consuming frequencies).

The good new is: you can now listen to the .1 channel which should be a very nice addition ;)
Some questions:

1/ On my Sony receiver, there are separate settings for crossover frequency and speaker size. I have set speaker size to large because I feel I get a not-small sound out of my Infinity speakers in the front. I want the fronts to reproduce as much of the bass as they're physically able because I don't like it when I can tell that the bass is coming from elsewhere (the subwoofer). The 80 Hz crossover frequency and subwoofer placement in front appears to have accomplished that. What does the Big/Small setting actually do to the sound? I haven't done any experiments or tried to look it up in the manual but I personally suspect that this setting determines where the bass is routed if you have no subwoofer (see below) and thus has no bearing if a subwoofer is attached to the system.

2/ I know that putting the sub in the corner will improve it's sensitivity and I may do that if I find the ESW-8 losing steam. It is a surprise to hear that positioning might improve extension. Where did you get this information?

3/ I was under the impression (I think by something I read in the manual) that in my previous setup, since I told my receiver that I had no subwoofer, it would mix the LFE into the main speakers. So I think I had .1 before but now I'm able to hear it at full level down to 32 Hz instead of only down the 60 Hz.

canuckle
01-10-2009, 11:56 PM
1/ On my Sony receiver, there are separate settings for crossover frequency and speaker size. I have set speaker size to large because I feel I get a not-small sound out of my Infinity speakers in the front.
This is just the wrong way of looking at it. Your subwoofer reproduces more bass with greater ease, therefore it should be the speaker dedicated to the task. Taking that strain off of your main speakers will allow them to reproduce the rest of the sound better. Have a thorough read of this (http://www.audioholics.com/techtips/setup/loudspeakers/bassmanagementbasics.php).


I want the fronts to reproduce as much of the bass as they're physically able because I don't like it when I can tell that the bass is coming from elsewhere (the subwoofer). The 80 Hz crossover frequency and subwoofer placement in front appears to have accomplished that. What does the Big/Small setting actually do to the sound?
You cannot localize the subwoofer when it's being sent signals under 80Hz period. That does not constitute an argument for forcing the fronts to reproduce sounds that they are not best suited to. Large/small has nothing to do with the end sound; it's just about how to split up the signal amongst your speakers.


2/ I know that putting the sub in the corner will improve it's sensitivity and I may do that if I find the ESW-8 losing steam. It is a surprise to hear that positioning might improve extension. Where did you get this information?
Technically, the sensitivity remains the same since that's an anechoic measurement. Measuring extension is done by determining the lowest (-3dB) point of the speaker for a constant input level. When you place the sub in the corner and add the benefits of the boundary gain, it's louder and therefore the -3dB point becomes lower. Voila... more extension. Since you've increased the output of the speaker using the room, the -3dB point has moved closer to the -10dB point.


3/ I was under the impression (I think by something I read in the manual) that in my previous setup, since I told my receiver that I had no subwoofer, it would mix the LFE into the main speakers. So I think I had .1 before but now I'm able to hear it at full level down to 32 Hz instead of only down the 60 Hz.
The Subwoofer channel requires a 10dB gain applied to it (by design to allow for more recording headroom) so it cannot easily be folded into the mains the same way that you can fold surrounds into the mains when you don't have them. While there's nothing in the LFE standard that prevents a receiver-manufacturer from directing the LFE to the mains in the absence of a subwoofer, it's not done in actual practice because it would be a good way to blow speakers. If you don't have a subwoofer hooked up, the LFE channel is just disregarded.

Kevio
01-11-2009, 08:10 AM
Thanks very much for the reference (http://www.audioholics.com/techtips/setup/loudspeakers/bassmanagementbasics.php). With speakers set to large, they bypass the crossover and interfere with what the sub is trying to do. Make sense to set to small. Why is the option even available?

Thanks also for the LFE explanation. I find it a little hard to believe that a receiver manufacturer faced with the choice of more bass vs. protecting your speakers would go the conservative route. But, with my new subwoofer, I am hearing stuff in movies that I did not hear before so what you're saying seems to be true.

As far as putting the subwoofer in the corner, I'm not satisfied with your explanation. Here's a reference (http://www.audioholics.com/tweaks/get-good-bass/subwoofer-placement-the-place-for-bass-part-1/subwoofer-placement-the-place-for-bass-part-1-page-3) I found. In short, the corner position will raise the reproduced level but does not change the roll-off frequency (extension). When I put the subwoofer in the corner. I'll get more bass below the speaker's roll-off frequency but I'll also get more bass in the speaker's passband. I'll need to turn down the gain to the speaker to balance the system and in doing that, I'll be back where I started in terms of extension.

StevenSurprenant
01-11-2009, 08:10 AM
I've owned several different subs and now I have a HSU .

With my earlier subs, integration was difficult because the slope on the high side of the crossover was too shallow. You could hear this by playing the sub by itself. I would clearly hear the voices coming out of the sub. The HSU is better in this regard and integrates easily. The problem with a sub that has a shallow slope at the crossover point is that you need to set the volume very low to get it to integrate and in doing so, you don't get the volume you need from the lower bass registers.

With that said, the second biggest problem with subs is that people want to hear alot of boom so they turn it up to where they think it should sound like apposed to how it was really recorded, then when the real bass happens it sounds all bloated and boomy. You hear this all the time in stores. When set up properly, you will never even know you have a sub except that everything has more body and bass.

How to set up a subwoofer...

http://reviews.cnet.com/4520-11254_7-6360441-7.html?tag=rb_mtx;wp_body

"Move your comfy chair or sofa out of the way and temporarily put the sub in your prime listening position. Play music with lots of bass and set your disc player to repeat a 10- to 20-second section with a variety of bass notes--we use Holly Cole's Temptation CD. Now take a little stroll around your room, slowly walk, or better still, crawl on your hands and knees (really!) around the perimeter, then out in the middle of the room. Chances are, you're going to hear a wide variation of the quantity and quality of the bass. It may nearly disappear in some spots, and in other places, the bass will be oppressively heavy. Keep moving, and you'll probably come across a point or two where the bass is nicely balanced; all the notes should be equally loud. Assuming at least one of those spots is domestically and aesthetically acceptable, move the subwoofer to that point. (Now you'll be glad you invested in that extralong cable.) Next try a few different bass-heavy CDs and DVDs to confirm the position. Once you're sure, place the sub in the spot that sounds best to you."


The same thing applies to your main speakers. My speakers are taller than me, but when the music plays I hear nothing coming directly from the speakers so totally I forget about them. The sound seems to be coming from a 3D space behind the speakers.

My room is rather small, but the speakers are about 5 foot from the front wall and spaced about equidistant from each other and where I sit. This setup doesn't bode well with most women, but if you're wanting a 3D soundstage, this seems to do it. I might also mention that if your seating position is further from the speakers than the speakers are from each other, you loose the soundstage. Of course, this will vary according to how much you have the speakers towed in or out.

I could say more, but you probably know all of this already. I apologize if this is too much information.

Enjoy!

canuckle
01-11-2009, 04:46 PM
As far as putting the subwoofer in the corner, I'm not satisfied with your explanation... In short, the corner position will raise the reproduced level but does not change the roll-off frequency (extension). When I put the subwoofer in the corner. I'll get more bass below the speaker's roll-off frequency but I'll also get more bass in the speaker's passband. I'll need to turn down the gain to the speaker to balance the system and in doing that, I'll be back where I started in terms of extension.
Okay, but of course you'll get less sound if you turn the gain down. You don't have to even move the sub to come up with that result ("I turned my sub down a quarter twist and got less extension than before" - yes you did!). Measuring extension does not take into account "balancing" the speaker in with your system - it simply measures how many dB of sound is produced at different frequencies given a certain input. When you place the sub in the corner, you get more dB than a centre-wall placement for the same input. More dB = lower extension. Period. That you then turn your sub down and change that measurement does not invalidate the fact that the result was what it was.

As far as the real world goes, perhaps I assumed some things that I just take for granted nowadays. The curve is no longer static as you portray it to be on account of almost all of today's quality receivers having some type of RoomEQ built in. Such systems will attenuate only parts of the subwoofer's curve to reach the +/-3dB boundary (lets use Audyssey and say 64 bands between 15-120Hz). They will leave anything already within the +/-3dB zone alone. Thus, you don't have to adjust your gain to "balance" the sub with the rest of the system - you just leave it as is and enjoy greater extension. I will qualify my statement as such: In the real world with Audyssey, MCACC, or YPAO, a corner placement will most certainly lower measurable extension of your sub while properly maintaining each speaker's output to the reference standard.

Kevio
01-11-2009, 09:34 PM
I've done some additional setup today.

I was able to confirm that the "Large" passes bass to mains and to the subwoofer. I'm now getting better bass definition and consistency around the room with my mains set to "Small"

When I got the sub dialed in to the right level, it is difficult for me to hear the difference between 60 Hz and 120 Hz crossover frequency. Running the crossover frequency up and down actually seems to be a reasonable way to set your subwoofer level. If you notice less bass at the higher crossover frequency, your subwoofer needs to be turned up.