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Does R11 need dual subwoofer?

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simplywyn

simplywyn

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If the basement has concrete floors and walls, it will be less lively in the bass region than typical rockwall over wood frame walls and wood floors. In a concrete basement, the surfaces don't "chime in," adding their own secondary energy. In audiophile terms, you may find the bass "tighter" but "lacking bloom."

Boom this may be it, the wall behind the Q950's is dry wall, whereas the wall behind to the sides of the R11 is concrete
 
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simplywyn

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Hi
Short answer: Yes.
The best bass in most any room is obtained with subwoofers, properly integrated with the mains. The R11 need subwoofers. Any speaker need subwoofer in other words it is always better to use subwoofers.

To the OP. I will try to keep the rationale for my reply condensed, the subject is however a little bit complex and could require more…

It is important to understand that the reproduction of bass depends on the room. You could have a speaker capable of reproducing 10 Hz to 20 KHz flat, no bump, no variations at 120 dB at 4 meters; once placed in a room it becomes subject to the room influence and to the position of the listener with respect to the low frequency radiators in this example, the speakers. It could be thus, that the placement of your Q950, provides you with a better bass sensation than those of the R11... or it could be where you sit, or it could be the rooms dimensions, or it could be the room construction... or it could be all the above. The last bit could sound flippant or dismissive. It is not.

The perception of bass, to make matter more complicated, is not linear. Let’s suppose the example of a perfect speaker, linear from 20 to 20,000 Hz within 0 db. Flat and no THD, driven by a perfect amplifier. For this mind experiment we suppose also perfect measuring instruments and a humongous anechoic room, so speaker will play as flat as it can. And a perfect SPL meter too . We measure 50 dB at 1000 Hz… We, again measure it at 500 Hz, then 20 Hz. The speaker and room (anechoic) being perfect, we measure 50 dB at 1000 Hz and at 500 and at 20 Hz and... at any frequency in between, 32.01 Hz or 100 Hz .. same sound pressure level: 50 dB. We place a human subject and ask her/him/they to give us her/his/their perception of “loudness”.. How loud are the tones? Well, in this perfect room, with perfect speakers and perfect everything. Playing 20 Hz at 50 dB… This human with perfect hearing will barely perceive the 20 Hz… if at all… Keep this reference in mind. We’ll have to come back to it. Those are the famed Fletcher-Munson curves.

To make matter more complicated, it also happens that in most rooms, the best position for bass is not that for best soundstage, or the rest of the spectrum.It has been studied by people at Harman and by other independent audio scientist, namely Earl Geddes that the best bass in a room in various position is obtain with multiple subwoofers placed in certain positions. Harman preconizes some specific positions for the subwoofers, Geddes advocates a different approach, he calls it quasi-random with one subwoofer in a corner (let’s call it the main subwoofer, the most capable) and the others literally somewhere on the opposite wall and the third behind the listener. In the Geddes approach if the main speakers in this case your R11 are capable in the bass it makes the resulting bass response at the listening positions (plural) smoother and more linear.

The better subwoofers are in general more capable in the bass than most mains, even celebrated and/or expensive ones. A good $1000 subwoofer is quite capable to provide 20 Hz at 110 dB at 2 meters… Few mains are so capable, very few… Cite me two mains that are so capable ;) … Of course you will say that you never play this loud but remember the Fletcher Munson curves? 100 dB in the bass at 50 Hz is perceived to be less loud than 100 dB at 1000 Hz and few mains are by themselves so capable. @sweetchaos at a marvelous subwoofer comparison tool to guide you in the choice of subwoofers, it would be wise to use it.

Independent subwoofers afford you to place them where they provide the best bass, more extended and smooth bass at the listening positions? You place these where they play best, provide you with the best bass and place the mains where they play best.. no reason to compromise. On top o f that there is the subject of constructive inteference. The room play havoc on the bass. You have points in the room where the room adds bass while substracting at other point. Multiple subwoofers canhelp taming those variations.

The process of integration is not easy. Let’s be clear about it. It is however doable and there are methods to achieve it. None are slam-bang-you’re done! It takes days, even weeks to achieve. One thing to be sure in trying to integrate is the necessity of DSP aka Digital Signal Processor/ing and EQ. You will have to learn to measure and to interpret measurements. This will take time and effort

I have to cut it short . You need subwoofers but the integration is not an easy task. It takes time and efforts. It will however (almost a guarantee) provide the best bass you have ever heard, provided you use capable subs and you work on integration. People here will help if you need it. If you have more question. Ask. The level of knowledge from the people here is high.

Peace.
Thanks for this reply, very useful
 

Chrispy

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Construction it seems could be a contributor to an extent, how about size/volume, furnishings, etc ? Can be hard to compare two different systems in different rooms. How about getting a measurement mic and REW or something to "see" what's going on?
 

BrokenEnglishGuy

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Room it's highly important factor in bass performance, in my room I got 30hz +0dB, only because I got '' fun room gain ''. Im using Kef r7, i posted my measurements in this thread.
 

Mowz

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I have R11s in my office. They can be equalized flat to 20 at most volumes, but because I like bass and my office sucks for reflections I use subs. 1 sub gets me to 20 easy, but my room modes also suck so I use more.

I love the r11s and before had ls50 metas. I found I prefer the full range speakers to the metas with subs, which I still love and use at home.
 

MAB

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Nice speakers! Concrete floors in your basement, right? Very difficult to compare speakers in a concrete room to speakers on floors upstairs. Much of the perceived bass punch is from your feet and chair on the floor and concrete will change that perception massively. Also the basement likely has different ringing. Lastly, you may have an odd room mode in the basement that is damping the bass (some long duct acting as a resonant absorber, some odd dimension of the room, etc.) Have you tried swapping speakers around to see if it is speaker or room?

Subwoofers with those R11 speakers will be awesome. But it would be good to understand your room more first I think.
 

DavidMcRoy

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The basement construction will be less "lossy" so there may also be more bass overhang/ringing and the upper-mids and treble might be somewhat exaggerated.

Another possibility would be personal preference for a more coloured presentation.
Believing that flat frequency response and less low-order harmonic distortion is universally preferred might be wishful thinking...
Yes. I just moved into my first house that "has" a basement (from Florida to Washington) and built a media room down there. I've always immediately done extensive room treatment in a new place, so I hadn't thought about that spectral balance shift you get if you don't do so, since I pretty much fix it before I can even experience it.
 
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simplywyn

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I’ve held off buying subwoofers so far simply because shipping them costs almost half the subwoofer in Canada these days

I’ll have to pop into a mono price of a svs store in the states and drive them up to Toronto manually at this point

The bass is better now that I’ve filled the basement with more items, oddly enough
 

BrokenEnglishGuy

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I’ve held off buying subwoofers so far simply because shipping them costs almost half the subwoofer in Canada these days

I’ll have to pop into a mono price of a svs store in the states and drive them up to Toronto manually at this point

The bass is better now that I’ve filled the basement with more items, oddly enough
bass is placement depend, in my small room my R7 have usable 30hz bass and 25hz it's at -6dB which is pretty dam good for a pair of '' relative small towers '', but ur room its much bigger than mine, my R7s are not going to deliver the same amount of ''tactile-bass''


But yeah Kef created the KF92 for a good reason too, if the room it's big and you wanna solid bass..
 

Cote Dazur

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:D
You beat me to it.
Yes, :D, me too, exactly how I felt when reading the post and yours made me smile.
As to the OP, a lot of great post in this thread, #18 in particular.
To the OP, switching the speakers ( but keep them in each other position) and listening for a while to both in each other position would be what I would do first, it should help you understanding what you are struggling with. My money is that it has nothing to with the speakers ( even less with what is feeding them ) but 100% with different room and speaker/seating relation. My money would be, from personal experience, speaker position withtin the room and to seating position. Put sticker on the ground before switching, as you probably going to switch back and forth a few time before you understand, do not ask how I know. :D
About subwoofers, as great as they can be, if you do not feel the need for them in your Q950’s set up, it is probably not what you need
 
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simplywyn

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The KF92's are integrated, and breaking in. Subwoofer break in is SUPER real, I've experienced it with every subwoofer I bought. Takes around a 24 hours of playing music to really start getting those low notes to shine. (so takes about a week of regular 1 hours or so platy time a day)

At the beginning I thought I was a fool, wasted the money, put it at 120hz crossover and started hearing something at least. At 40hz, nothing, but empty noise and shaking windows.

After 2-3 days of continuously playing them, I'm beginning to hear the benefits. At 40hz cross over now, they really make disappear into the sound field and man when the bass comes in it's a delight.
 
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Chrispy

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The KF92's are integrated, and breaking in. Subwoofer break in is SUPER real, I've experienced it with every subwoofer I bought. Takes around a 24 hours of playing music to really start getting those low notes to shine. (so takes about a week of regular 1 hours or so platy time a day)

At the beginning I thought I was a fool, wasted the money, put it at 120hz crossover and started hearing something at least. At 40hz, nothing, but empty noise and shaking windows.

After 2-3 days of continuously playing them, I'm beginning to hear the benefits. At 40hz cross over now, they really make disappear into the sound field and man when the bass comes in it's a delight.
You're the one breaking in....
 

MAB

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The KF92's are integrated, and breaking in. Subwoofer break in is SUPER real, I've experienced it with every subwoofer I bought. Takes around a 24 hours of playing music to really start getting those low notes to shine. (so takes about a week of regular 1 hours or so platy time a day)

At the beginning I thought I was a fool, wasted the money, put it at 120hz crossover and started hearing something at least. At 40hz, nothing, but empty noise and shaking windows.

After 2-3 days of continuously playing them, I'm beginning to hear the benefits. At 40hz cross over now, they really make disappear into the sound field and man when the bass comes in it's a delight.
Glad you got your subs, they must be great.
Regarding breakin, it's actually not a thing. Here is a good article, with measurements.
I've measured similar. The TS and the non-linear parameters don't appreciably change. And the small changes that do happen occur after the first use.
So enjoy right out of the box. Focus on placement on room interactions, not the breakin.
 

Chrispy

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Yeah sure, this entire hobby is mostly bullshit and fraud anyway
That's the way it works, tho. The changes in t/s parameters to a driver is miniscule and often returns after rest anyways. There is a lot of bullshit....like break-in for the most part.
 

HarmonicTHD

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My two KF92s are unchanged since 2 years from the first sound they played luckily. Or for that price I would return them if they would “break in”. Confirmed by REW I took after I bought them and recently again.

Get REW and a UMIK the 100 bucks are vanishingly small compared to the rest of the system. At least you can stop guessing and worrying what is changing and what is different between all the various setups (speakers, positions, subs, xovers and delays, rooms etc).
 
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simplywyn

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I’ve literally experienced subwoofer break in to the point where I would return them then later

It only takes a bit of time, not talking months here, maybe 1 hour total play time to break it in.
 
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I’ve literally experienced subwoofer break in to the point where I would return them then later

It only takes a bit of time, not talking months here, maybe 1 hour total play time to break it in.
Let's not get too polarized. It's not black or white. If there are moving mechanical parts, sure, there may be some wear and tear or break-in. Also if your new speaker have been stored at a warehouse for months, transported and unpacked at destination in your living room where temperature and humidity is different. -This does influence the performance, it's a fact. Of course the degree of these two parameters' combined influence on the speaker performance vary wildly according to materials used in the driver and cabinet and climatic differences.

It's most likely that the person experiencing the perceived change in performance is getting used to the sound at the same time the speaker is breaking in so it is actually a combination of the two poles.

So my assessment is that NO ONE can conclude if these differences are heard or not without measurements at unpacking time vs. measurements at unpacking time +100 h.

Let's try and be civil and not just dig fox holes for each opinion we have.
 

HarmonicTHD

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I’ve literally experienced subwoofer break in to the point where I would return them then later

It only takes a bit of time, not talking months here, maybe 1 hour total play time to break it in.
Facts please, it is not a matter of opinion or finding a consensus. You can’t rely on your hearing with such things you have to measure and REW is easy and cheap to do.

However that doesn’t mean that something doesn’t gets broken and needs fixing or replacement.

Besides you will never find the optimum placement of sub, speakers and xover for your particular room without measuring. Simply too many possible combinations. And why save 100 bucks when you spent some 5000 on the KF92s or so alone.
 
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