[AJinFLA]

Hm, well, if located out in the room, a larger speaker would have half-space radiation down to a lower frequency, which would be an advantage in terms of reducing reflections from the front wall. Am I warm?  That is of course for a box speaker.

Correct, which is typically what folks are using. A rear measurement of any small>medium size monopole is quite revealing and may surprise many. Now of course, large speakers tend to extend lower, many being reflex designs, to have flat free space response, which is usually disastrous in a small space. So in that sense, small is often better. Not by design per se, but by the consequential limitations of physics of small (passive) boxes.

cheers,

AJ

[AJinFLA]

You might need to drop me a bone on that one... I've thought for a while that corner speakers are the best approach in a small room - currently experimenting with/listening to monitors pushed into the corners of my study. The actual size of the speaker should make no difference.... I think... soo.. what is it about the size of a large speaker that would be an advantage in small rooms (instead of merely irrelevant)?

If you want to maximize stereo precision imaging, by minimizing reflections, then yes, corner speakers are the way to go for a small room. This trades for spaciousness, but if the recording has depth, won't be as bad. Like DS21 alluded to above, bigger speaker = bigger horn load/waveguide to limit the directional characteristics of the speaker, as you noted to lower frequencies. It's of course all about trade offs.

cheers,

AJ

p.s. don't want to start any wars, but effective broadband...and it must be relatively linear/frequency independent broadband "treatment" would further shrink the size of the room.

[JohnR]

Now of course, large speakers tend to extend lower, many being reflex designs, to have flat free space response, which is usually disastrous in a small space. So in that sense, small is often better. Not by design per se, but by the consequential limitations of physics of small (passive) boxes.

I heard a fair amount of that at last weekend's Sydney Audio Show. A few vendors commented on room acoustics, and in one room a perceptive bystander (I assume) piped up "but this room is probably what a lot of people have for their listening room." And that did get me wondering - why don't speaker manufacturers design speakers to work in the spaces that people actually have? Yes, there will be compromises but a speaker designed to work with the limitations of a real room/placement will surely fare better than one designed for an ideal situation that is then placed in a compromised situation....

There used to be corner speakers and on-wall speakers. But you don't see them any more (except for HT surrounds). Yet when a non-audiophile asks me about speakers, it turns out that that is where they are going to put them...

[JohnR]

If you can fit wider narrower-directivity speakers in the corners of a small room, that would likely be a good bet.

I was thinking about speakers designed specifically for corner placement. In that case, aren't they 90-degree directivity by definition? (Up to some frequency where they might narrow more.)

I'm afraid I don't follow your comment about planar drivers. My point there is that an ideal dipole response is symmetrical, which is more feasible with planar drivers than cone drivers. (Yay, back on topic! )

[AJinFLA]

I heard a fair amount of that at last weekend's Sydney Audio Show. A few vendors commented on room acoustics, and in one room a perceptive bystander (I assume) piped up "but this room is probably what a lot of people have for their listening room." And that did get me wondering - why don't speaker manufacturers design speakers to work in the spaces that people actually have? Yes, there will be compromises but a speaker designed to work with the limitations of a real room/placement will surely fare better than one designed for an ideal situation that is then placed in a compromised situation....

Absolutely. You see it every show. A few folks getting good-great sound in one room...and in the adjacent exactly same (hotel) room layout next door...poor sound. What happened? What changed? The room? Or the acoustic sources in the room. 95% of the "high end" market is gorgeous jewelry that has transcended the limitations of physics that plague mere humans.
Not all mind you. Linkwitz, Salmi, Olive and Geddes et al are leading the charge, but are basically an obscure fringe group in the larger sense. I have seen some fairly "hi end" type on walls (and even in walls) recently, but of course, with astronomical price tags unfit for the peasantry. Of course, for folks like you, there is always DIY.

There used to be corner speakers and on-wall speakers. But you don't see them any more (except for HT surrounds). Yet when a non-audiophile asks me about speakers, it turns out that that is where they are going to put them...

I would imagine this is quite prevalent, especially in Europe where typical listening spaces are more restricted. But here too, in city centers where indeed, a corner or wall speaker may work best. From a commercial standpoint, a restricted radiation type should be successful if available to this market. But how are you going to convince the audiophile who believes and is absolutely convinced, that say, a speaker devoid of the divine RAAL tweeter...and its 180+ degree radiation...is best for them, in a small room, when they know/have read no other tweeter comes close to matching its "sound"?
See the dilemma?

cheers,

AJ

[AJinFLA]

My point there is that an ideal dipole response is symmetrical, which is more feasible with planar drivers than cone drivers. (Yay, back on topic! )

Laterally for sure, it's easier to do with planars, though it could also be done with multiple cones of similar radiation dimensions.

cheers,

AJ

[JohnR]

See the dilemma?

I do, but that's marketing, in the specific case when crappy sound is attributed to a "crappy room" you would think... well, you would think a demo of good sound in the "crappy room" would speak for itself. FWIW the best (by far) sound was a room with hefty dipoles, some absorption on the front wall, and electronic correction. Well, the room with the HD800s sounded pretty decent too 

Laterally for sure, it's easier to do with planars, though it could also be done with multiple cones of similar radiation dimensions.

I'm not sure I follow... are the cones facing both ways? My measurements show poor symmetry with cone drivers front relative to back.

[lowtech]

I don't understand what the last dozen posts about speaker size in a small room have to do with the LX521. 

[JohnR]

I don't understand what the last dozen posts about speaker size in a small room have to do with the LX521.

The LX521 is a large speaker.

Hope that helps...

[lowtech]

Planars, DS21, corner room placement, Sydney Audio Show, etc.  Nothing to do with LX521.

The design requirements are clearly stated: http://linkwitzlab.com/LX521/Description.htm

• Room size: >240 ft2 (>22 m2) area,  >8 ft ceiling
      Speaker placement measured from tweeter:
      >4 ft from wall behind it, >2 ft from side walls,
      speaker separation >8 ft
• Listening distance 8 ft to 18 ft depending upon loudspeaker application
• Room acoustics: Fairly live with RT60 of 400 ms to 600 ms for a natural living space

Hope this helps.  (Most would consider your diversion from the OPs topic a thread hijack).

[JohnR]

Hm. Well, you know, I think the question about planar drivers is valid. How come Linkwitz didn't consider them? Or did he?

[lowtech]

I can't speak for him, but I do know that he's tested a few, including the Neo3.  That driver would not work in this design.  He also tested it for use in another design and found the levels of distortion and dynamic compression unacceptable.  One of the design goals (from the same link as my prior post) states:

• Open-baffle, dipolar radiator, < 20 Hz to 20 kHz,
  Acoustically small in the horizontal plane through the upper midrange

I would imagine a planar driver would not allow him to meet this goal.

[JohnR]

I'm still left wondering if the difference between front and back is even considered when talking about "dipolar radiation." With a crossover frequency of 7 kHz, I'm assuming that the back radiation is a mess. But I don't know to what extent it's important and/or what the criteria are. I don't have a 10F but IIRC you do - ? Have you posted measurements of the rear somewhere that I can see?

[AJinFLA]

I'm not sure I follow... are the cones facing both ways? My measurements show poor symmetry with cone drivers front relative to back.

I meant smaller pistons operating within their omni range. Yes, asymmetry there would be an issue if you are aiming for (near) perfect dipole symmetry. I just noticed the very high XO to the tweeter. You are correct that asymmetry there should be an issue...unless not a goal of the design. Can't imagine the rear structure not affecting radiation at those frequencies of a small cone. Guess the proof will be in the (system) pudding.

cheers,

AJ

[Telstar]

I listened to the Orion about 2 years ago.
They look as an improvement, the baffle shapes and sizes are well studied, and i'm sure SL did the math correctly.
The crossover/asp unfortunately doesnt look any cleaner for the signal path and i'm afraid that this will cripple the potential of the speakers as much as it did for the Orions.
Second thing that could be risky is this "Passive 1st order crossover between lower midrange and upper midrange at 1 kHz, located in base of midrange/tweeter baffle" mostly because of the frequency where the cut has been done (a 1st order passive is usually fine).

Edit: asp not dsp (thanks god)

[lowtech]

The crossover/dsp unfortunately doesnt look any cleaner for the signal path...

Fortunately it's not a DSP.   

[grsimmon]

First,  I could never understand why he refers to Pluto as an omnidirectional speaker, because it's not.  Partly, yes;  fully, no.   Duevel and Morrison speakers are omnidirectional.

Second, I cannot for the life of me understand why he has pursued these new speakers,  X521 or whatever.   Over the years, he has stated numerous times in his writings that omnidirectional and dipole, when properly designed, are close in performance.   If he holds omnis in high esteem, why not pursue an assault on omnis "done right",  similar to his efforts on the Orion?   World's first fully active, full omnidirectional, possibly open baffle if he could figure it out.   Or planars, as someone mentioned.....