[Nuance]

I ask because regardless of the sub I used, I can locate a single sub. 

What is your room like?  What crossover FR?  Have you tried other locations? 

I had the same issue at my old place until I found a better location for the subwoofer.  Once moved to the left corner, about 2 feet from the wall behind the speakers, the bass came from everywhere in the room, not just the corner the sub was in.  The room was 14x21, for what its worth.  Perhaps your room is much smaller (did I miss the dimensions)?

[Nuance]

If the sub has a 24 dB per octave crossover at 100 Hz, its output will be down by about 100 dB at 1.5 kHz.

The ear does not process sound like I think you are envisioning; much of it is counter-intuitive.  De-correlation at low frequencies is desirable in most situations.

Wait, so you are saying phase isn't important below the crossover frequency?

[Niteshade]

I have a question:

Am I really missing anything by not having a sub? My speakers go down to around 35hz and do a fantastic job with bass. I am a near-filed listener and don't get any further than 8ft away from my speakers. Granted, I'll miss what is below 35hz, but how much is there below that? (Good question , acutally!) Are there that many instruments that can play below 35hz?

[DougSmith]

I have a question:

Am I really missing anything by not having a sub? My speakers go down to around 35hz and do a fantastic job with bass. I am a near-filed listener and don't get any further than 8ft away from my speakers. Granted, I'll miss what is below 35hz, but how much is there below that? (Good question , acutally!) Are there that many instruments that can play below 35hz?

I would say: probably yes...  For much music there isn't much in that lower register, bit for other pieces it adds quite a lot.

[cujobob]

Subwoofers are nice because they can help EQ out some of the in-room craziness that happens below 200 hz....amongst other things.

If you can locate your sub, it might be due to bad in-room behavior as well as the setup.  Measurements should tell you what's going on..if your FR is flat and you can still localize the sub, I'm not sure.

[doug s.]

I have a question:

Am I really missing anything by not having a sub? My speakers go down to around 35hz and do a fantastic job with bass. I am a near-filed listener and don't get any further than 8ft away from my speakers. Granted, I'll miss what is below 35hz, but how much is there below that? (Good question , acutally!) Are there that many instruments that can play below 35hz?

i think you are missing a bit by not having a pair of stereo subs flanking your mains, actively crossed over.  as i stated earlier, when i first did this, my mains were -2db at 20hz.  not only did the bass improve w/the subs crossed at 80hz, but the mains also improved, as their 10" woofers and their amps were less stressed, not having to see anything below 80hz...

doug s.

[Quiet Earth]

Am I really missing anything by not having a sub? My speakers go down to around 35hz and do a fantastic job with bass.

No, your not missing anything.

Except I do remember that I used to have a lot more cables, amplifiers, filters, test recordings, and constantly adjusted the subwoofer level(s) for different recordings. You are missing that. (Just making a little counter point for the fun of discussion.    )

I guess the real moral of the story is that it's up to you to decide what you prefer. How far are you willing to go to achieve technically perfect bass? Does it improve the overall listening experience? No one can answer this for you.

I'm actually open to trying it one more time. We'll see.

[Nuance]

Niteshade,

I agree with the statements above: the tuba, organ, pipe organ and grand piano all reach down below 20Hz.  I use subwoofers because it naturally improves the FR response, plus it allows me to apply any necessary PEQ below the crossover.  I had to apply a few filters due to a peak at 50Hz.  Obviously things sound much better now.    Also, my speakers utilize two 5" drivers in each, so naturally the subs win the displacement battle. 

Here is what my in-room response ended up being by utilizing more than one subwoofer and a little PEQ:




It sounds vastly different!  With the large peak at 50Hz everything was bloated and smeared, but now...well, its like a totally different system, for the better. 

On the other hand, what Quiet Earth said is of most relevance.  In other words, you have to try it out yourself and decide which is better.  Going the subwoofer approach isn't exactly the easiest route, but if done properly I feel it yields the best results.  YMMV. 

[doug s.]

once i have dialed in my subs, i have never had any need to adjust the subwoofer level for different recordings.

you don't have to be a bass freak to enjoy improved soundstaging, improved upper bass & lower midrange, improved foundation to the music, improved room integration - all these thing happen w/subs properly crossed over to monitors, imo.

ymmv,

doug s.

[simon wagstaff]

I find a great improvement with using two subs, one in each corner, VMPS smaller subs with 250 watts each. Whatever the crossover frequency I used to be able to locate the single sub. I also have a pair of Infinity Intermezzo 4.1 that have a built in sub with 850 watts each. I use an AVA U70 to drive the Infinities and take great glee in the fact that I have 2,200 watts for the subs and 35 watts for the rest. I dial down the subs in the Infinities just a bit and level match the subs. I achieve true bass lock in my room. I believe that Phil Lesh deserves nothing but the best!

And Andreas Vollenweider Caverna Magica is awe inspiring in my room.

[rockadanny]

I do I do! Though it is a passive cross-over in that I run my mains full and just augment the LFs with a pair of subs. They are set so low (each to 35Hz, though produce higher in room bass than that) that they in no way interfere with the quality of sound from my mains and draw no attention to themselves at all. Not only do they dig deep (-7dB at 15Hz) but they also add a great amount of fullness to the mids as well. Before I got a second sub I used to pine over mains which produced lower freqs. than mine, which are rated -3dB at 55Hz. Once I added a second sub I was glad they only reached -3dB at 55Hz so I could allow my subs to take over in a more controllable fashion without interfering with the mains. I was able to smooth out the LF response with greater ease due to changing sub locations rather than main relocations. Multiple subs (at least two) was the key for me.

[ctviggen]

Nuance, that's an amazingly flat spectrum, even with EQ. 

[Wayner]

That is quite the output at 17Hz?

Wayner

[DougSmith]

Here is what my in-room response ended up being by utilizing more than one subwoofer and a little PEQ:
It sounds vastly different!  With the large peak at 50Hz everything was bloated and smeared, but now...well, its like a totally different system, for the better. 

Looks nice... Measured at one position, or averaged across an area?  Many folks "tip up" the low end response a bit. I adjusted mine that way and found that it sounds a bit better (my subs don't go as low as yours, though):

[turkey]

Wait, so you are saying phase isn't important below the crossover frequency?

Phase isn't terribly important in the typical home listening room at bass frequencies. See Earl Geddes' comment I quoted earlier.

[Duke]

Wait, so you are saying phase isn't important below the crossover frequency?

The ear doesn't hear waveforms the way we envision them, at least not at low frequencies.  The spectrum, or the frequency response, is what matters in the bass region.  The ear is very poor at resolving in the time domain down there, so it doesn't care if the frequency response is the sum of in-phase and out-of-phase and random-phase energy.  To the extent that things like phase and group delay affect frequency response, they are audibly significant - but in and of themselves they generally are not.  I'm sure there are thresholds beyond which phase and group delay are audibly significant apart from their effect on frequency response, but they are not normally approached in a home music system.

[JRace]

I have a question:

Am I really missing anything by not having a sub? My speakers go down to around 35hz and do a fantastic job with bass. I am a near-filed listener and don't get any further than 8ft away from my speakers. Granted, I'll miss what is below 35hz, but how much is there below that? (Good question , acutally!) Are there that many instruments that can play below 35hz?

It is not what you are missing below 35Hz - it is more about what you are not getting from 35Hz - 100Hz. It is here that your main speakers may not be performing well do to their location. It is the ability to locate a separate subwoofer in the best location that makes it a benefit.

Have you ever measured your room?

[cujobob]

No, your not missing anything.

Except I do remember that I used to have a lot more cables, amplifiers, filters, test recordings, and constantly adjusted the subwoofer level(s) for different recordings. You are missing that. (Just making a little counter point for the fun of discussion.    )

I guess the real moral of the story is that it's up to you to decide what you prefer. How far are you willing to go to achieve technically perfect bass? Does it improve the overall listening experience? No one can answer this for you.

I'm actually open to trying it one more time. We'll see.

If your sub was level-matched, why would you alter the settings based on the recording?  It should still remain matched.  If you changed it based on preferences, then that offers you flexibility mains alone would not provide.

[Nuance]

Looks nice... Measured at one position, or averaged across an area?  Many folks "tip up" the low end response a bit. I adjusted mine that way and found that it sounds a bit better (my subs don't go as low as yours, though):

No - that was just at my LP.  Here is the averaged response of three listening positions (the three spots on my couch):



I wanted to try the natural rising thing but never got around to it.  Oddly enough, my receiver does it on its own, so my response looks more like yours for movies, but its flatter (as shown above) for music.  I think it turned out well for both, and I only had to apply three filters of EQ.  I am pretty happy, all things considered.  Your response looks amazing, by the way. 

[Nuance]

That is quite the output at 17Hz?

Wayner

Thanks.  Room gain helps a lot (dual 15" sealed TC2000 DIY subwoofers), else these suckers would roll off a lot sooner/quicker. 

Nuance, that's an amazingly flat spectrum, even with EQ. 

Thank you.  I am fortunate.  I like DougSmith's better, though.