I have no clue what "absolute constant directivity" speakers might be, either.
[Don't believe I've ever seen or heard one, tho.... 😉 ]
[Don't believe I've ever seen or heard one, tho.... 😉 ]
In the context of my post, it should have been self-evident that I meant a spoof version of the comment of Elias' which I was endorsing in that post. He wrote "Certainly the flat on axis and flat off axis response...." didn't compute.
I am not opposed to well-conceived directivity concepts*. But, like Elias, I am skeptical of extreme positions or when directivity is elevated to being one of the most crucial parameters (and which thread and guru that might bring to mind). For sure, a speaker's directivity advantages get mangled when they get installed in customer's music rooms.
*Dayton-Wright panels (8 ESL drivers per speaker) are mounted on a section of a sphere to simulate a point source whose origin is some place behind the speaker. How is that for a radical directivity concept?
The analogy is great, but the underlying purpose of that analogy doesn't seem to match-up with SL's intent.
1st of all:
I don't think that one design is necessarily better than the other. Is the Note necessarily better than the Nao II? The basic design is certainly more *uniform* and linear, but perhaps some might prefer the Nao II? A less directive pattern above 1 kHz (up to most fundamentals) might be preferable to some.
2nd:
I think the Orion is every bit as much a business venture as any of your commercial designs - which is to say, not it's main purpose. "Sales" of the Orion by SL are still limited to plans & circuit boards (stuffed or not), as well as well as a very limited selection of amplifiers (..which I believe is almost exclusively for uniformity and convenience). The contractor licensing (Wood Artistry) is simply a natural extension, and possibly something you should consider.
The major difference between both of your businesses is that SL's has been more successful - and probably due to much better marketing, though the design form-factor *also* plays a large role in it's commercial success. (..remember that the Phoenix never did particularly well, and early-on the Orion didn't do particularly well until accepting a contractor.)
3rd:
I don't think SL has a "reluctance to invest in something better", rather he seems to recognize quite well that perceived objective excellence does not necessarily equal subjective excellence. His approach seems less about the design, and more about the resulting sound. The Pluto is markedly different, and yet he felt that it has a similar presentation. It wasn't until comparing the Pluto to the Orion that he decided to try the rear tweeter (in all it's variations), because in some respects he preferred the Pluto. Up until then he clearly didn't think that he needed "to invest in something better". (..despite the opinions of others..)
In other words, I think you should look a little more deeply at your position. 😉
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I am surprised the way the thread is turning. I have several systems that I rotate in my 2 Way set-up. The range from cone and dome, old school horns and a modern CD horn set-up. It doesn't mater what the speaker type is if the recording stinks you can hear it plain as day warts and all on each system. Sure there are differences between the speakers but in all cases the source media is what rules.
The idea of hearing what's in the control room really isn't an issue at all. You set-up you room and speakers as best you can and in all cases you are at the mercy of the source material.
Rob🙂
The idea of hearing what's in the control room really isn't an issue at all. You set-up you room and speakers as best you can and in all cases you are at the mercy of the source material.
Rob🙂
Hi Scott,
All things considered I'll stand by what I posted. The rear tweeter thing is kind of interesting from an historical point of view, however. I recall back in the old Madisound days when I said I found it necessary to have a rear tweeter for my prototypes to sound balanced guys like mac chimed in and were quite verbal and emphatic in pointing out that SL had already shown that a rear tweeter was unnecessary. My use of the rear tweeter was considered somewhat of a joke and ridiculed . Several years later..., well history speaks for itself. The Orion now has a rear tweeter. The thing that bothers me is not that SL improved the speaker but that no one ever voiced a concern about the lack of a rear tweeter on the Orion, and apparently SL never recognized the need until he compared it to another speaker. Yet, when I prototyped my system it was pretty apparent. There was no need to compare the speaker to something else. The difference is not subtle. I literally designed the system initially with front only tweeters, build the prototype, measured it to be sure it met the design constraints, played it and said to myself, "That sucks". No rear tweeter was like throwing a blanket over the speaker. Now there is this shelving filter. It makes the speaker sound better. That again is fine. But, why did it take so long to recognize there was a problem? I just don't understand. I mean I have a shelving filter (actually a boost/cut shelf +/-3dB) on the Note and changing it from flat to -3dB is not subtle.
Now just quickly the difference between SL and my "business" is probably more along the lines that I don't take it seriously. As I have said before, I retired 13 years ago at age 50 because it just suits my life style. I don't need the hassle of "success". Been there, done that. I considered some form of trun key system years back and discarded it just cause it's not for me. I'm happy to share what I do but there is no need to make it into something other than a hobby. You know, the best way to ruin something you enjoy is to turn it into a business.
Anyway, I'm an engineer/scientist by pedigree and I'm just not satisfied with turning down the treble as a solution to what I believe is a more deeply routed problem.
And let me apologize in advance should anyone take offense with anything I say.
John, Does this mean you are going to stop charging to share your information and plans? Just curious.
Dave, I suspect you just misrepresented Toole yourself. 😉 I think Toole meant different directivities for different loctions in the same room, i.e. surround speakers vs front speakers, whereas you are talking about different directivities for different rooms (or room treatments). I don't think Toole supports that position. 😱
That is true, but my experience has been the better the speaker and room, the more good recordings I have and acquire. Better recordings keep improving. Perhaps other's milage varies, but there's no doubt here.
I would say that my Mackie monitors don't require as much room fiddling to sound great, but still improve a bit with it. Their off axis is a bit smoother than the Behringer and their pattern a bit narrower.
Dan
This is the old "recording music is not a controlled process" issue; Toole's "Circle of Confusion" in the audio industry.
Good recording studios fine tune the studio mix and master with listening sessions in a reference room. Really good studios do this in an IEC-standard room and with high quality flat-on-axis loudspeakers with a smooth off-axis response.
That's about as far as calibration/standardisation goes that I am aware of. And in that context, the logical thing to do is listen with high quality flat-on-axis loudspeakers with a smooth off-axis response, and use tone controls to adjust for variations in studio practices (not to mention hearing-impaired engineers and producers!). 😛
When I *try* to remember back to then 😀 , I *think* the exploration of a rear tweeter was for the Phoneix (and perhaps earlier), not the Orion. And at least when he tried that I believe it wasn't with the same *costly* tweeter at the same low freq. cut-off. (..in other words more of an "ambiance fill" use that he discarded.)
Also, your design is above 2 kHz for the tweeter, the Phoenix was at less than 1.5 kHz (as is the Orion) - at least conceptually the additional tweeter that low in freq. on a panel that isn't terribly wide does have problems in the form of increased diffraction and combing.
Given that, it's not difficult to see why the idea for the Phoenix or Orion was so easily dismissed (..and perhaps even ridiculed).
..and interestingly enough he limits his discussion on the Orion+'s dispersion to +/- 60 degrees.. I'd bet that beyond that limit it looks like hell. 😉
In other words a fairly slight difference in design led to different development paths.
I can understand the reasoning for not wanting to pursue it more commercially, but perhaps your reasoning and intention is not dissimilar to SL's. Consider that he *did* have a business based on his earlier work that he sold.. wanting to "tinker" instead and share his results with others where the cost of production is far lower and the hassles fewer. (..in fact I remember that he ditched most forum participation to further reduce hassles.)
I think SL's "hold-up" with the attenuation is relative to the front wall (or the wall behind the speakers), in other words he seems to be focusing on the reflection more than the direct sound which he otherwise dismisses. This is also evident in the supposition that you really aren't hearing direct sound more than +/- 60 degrees frontal. Erroneous IMO. In fact the reduction likely improves any problems with audible diffraction and combing as well.
As for taking offense.. nah, not a problem here. 🙂
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Yes, thats the paper, although I confess I tried to read through it several times last night and couldn't make headway. He had some odd conclusions, roughly: speakers should be omnidirectional laterally, since you probably can't design them with directivity that is constant. But they should have high directivity with regard to the floor and ceiling bounce, so as not to waste any power. No discussion of what the proper total directivity should be.
Ends up the perfect speaker was an omni with a cylindrical radiation pattern (like the recent B&O) that he happened to be selling.
David S.
Constant directivity studio monitors have been in popular use by recording engineers since the early 80's. I know because I designed a number of them for JBL.
Of course, their directivity is only constant for part of their frequency range. Usually for the range of the horn. I think their more important attribute is more even response over a broad listenng window.
Most studios are set up such that the engineer is in the near field or at least has a higher than average direct to reflected ratio. Under that situation does the far off axis response matter at all? What does that imply for home reproduction if we want to duplicate the studio experience? Is that really the right goal?
David S.
Hi,
Yes and usually in practise it means they are approaching constant directivity above about 2kHz. The irony here is that in normal domestic rooms this is also the range where room absorbtion is highest, and maybe even more importantly it may suggest that in this freq range the loudspeaker power response may not be that important actually (because very much affected by the room).
Thus one may think the best benefit of constant directivity may turn into usefullnes in the midrange (below 2kHz where room absorption is less). Accidentally this happens to be the freq range where dipoles can have constant directivity.
I enjoy my dipole line arrays at home very much. I've allways thought it's because of high direct to reverberant ratio, but your suggestion of it's similarity with the recording engineer point of hear may have some additional benefits.
- Elias
Yes and usually in practise it means they are approaching constant directivity above about 2kHz. The irony here is that in normal domestic rooms this is also the range where room absorbtion is highest, and maybe even more importantly it may suggest that in this freq range the loudspeaker power response may not be that important actually (because very much affected by the room).
Thus one may think the best benefit of constant directivity may turn into usefullnes in the midrange (below 2kHz where room absorption is less). Accidentally this happens to be the freq range where dipoles can have constant directivity.
I enjoy my dipole line arrays at home very much. I've allways thought it's because of high direct to reverberant ratio, but your suggestion of it's similarity with the recording engineer point of hear may have some additional benefits.
- Elias
Well I don't want to tread too deeply in these waters for the obvious reasons, but I am aware that SL experimented with rear tweeters on earlier designs and dismissed them. At one time he had a dissertation on his site as to why they were not needed. For what ever reason that changed.
I think you may in fact be on the same page I'm on. SL seems to prefer a more reverberant room and that may indeed mask some of these effects. You may recall that a couple of years after I build my speaker curiosity got the better of me and I build a pair of Orion speakers. That was back in '06, before the rear tweeter was added, and in my room the Orion suffered the same deficiency that my prototype did. Additionally, in my deader room more of the excess energy from the 90 degree radiation of the tweeter bloom is absorbed. Thus the rear tweeter serves more to balance the sound reflected from the wall behind the speakers. But if you focus on a more reverberant room and also focus more on the reverberant sound field as opposed to the direct sound, then as I have previously stated, the total radiated power becomes more of an issue than how or in what direction it is radiated. You start moving toward what Dr. Bose was doing 50 years ago, for better or worse. It's a different perspective. So when we start discussing this "flat is not correct..." I don't see how the discussion can proceed without all the caveats as to applied to what speaker in what room....., etc.
The point I am making here is simply that the idea that flat is not correct has to be take in context. And aside from how it sounds I think is is necessary to look at what it does. From my perspective the observation the the Orion may sound better with this shelf is an indication that the direction I have taken with the Note is on the right path. I believe that any improvement in the Orion is more a result of the reduction in the excess power radiated by the tweeters in comparison to the midrange than it is due to the non-flat on axis response.
Anyway, Have a happy Thanks Giving everyone.
I agree that his statement can be read both ways. However, I don't think it matters. I thought about this before I posted, I don't see how one can support one without the other. Moving location in-room excites room acoustics differently (as taking RT60 measures will show), and changes short term reflection delays etc. If these call for differing directivities, its logical to assume that using a different room could also.
I think we'd need more testing results to start to get a better grip on this interdependency. In its absence, I'm happy trusting my experience.
Hello Elias
We have all had experiences setting up speakers with differences in directivity in our own rooms at home. For the most part you can get them to work by moving them around, adjusting the toe-in, changing the listening distance and so on. It’s obvious we are adjusting the ratio of direct to reflected sound when we change placement and listening position.
What I am wondering is what exactly are we listening for when we do this??
Do we all have our own “Golden Ratio” of direct to reflected sound that we shoot for??
When we move the speakers are we unknowingly setting each pair up to that same ratio??
Are we adjusting for a higher ratio of direct to reflected sound if the reflected sound field is not smooth??
Rob🙂
The rationale of a diehard dipolist, obviously. 😉
I believe those of us working with constant directivity waveguides could successfully argue that wrenching control from the room is the better approach; it's a crap shoot relying upon it, otherwise. Once the loudspeaker is in control, the variables are easily manipulable to achieve the optimum balance.
Though I have been ridiculed for the suggestion in the past, I would not be surprised if Linkwitz weren't to settle upon a controlled-directivity waveguide as the ultimate solution to Orion's high-frequency power response issue.... 🙂
A plausible argument and kind of the other side of the coin to my "give PROPER controls to users."
But as I think about what could be shipped from the factory that would meet your purposes, all I can think of would be speakers with narrow beaming directivity. Anything wider would interact with a lot with different rooms differently. In fact, a narrow beam also interacts with rooms.
Sidebar: are we seeing here the old tug-of-war between "doctor knows best" versus "power to the people"? When I was young, nobody would sell a speaker without having controls on the back. Seemed nutsy and commercial suicide, at the time, to leave them off. Granted, with SL demanding you change 28 parts to make a teensie change in the sound, there are some good reasons not to have simple-minded L-pads and other crossover crude elements in the signal path for users to meddle with. But surely, some meddling is needed!
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