Further, I suggest one area where this is often the case among all designs - potentially even your own: the subjective perception of depth from a design.
The portion of my latest post that you quoted is the ONLY way I now how to OBJECTIVELY improve upon the subjective impression of depth, basically two very similar formats for creating an objective "depression" in the frequency response that usually improves the subjective impression of depth.
I don't know how to improve upon "depth" in any given design any other way than that, OBJECTIVELY. Other than that, I have never read anything other than subjective evaluation "tweaking" that has made an improvement in depth (in normal loudspeaker design).
Clearer?
Clearer, but I completely disagree that you or anyone else have an objective deffinition of "depth" such that anyone could design for it. What you propose as an objective solution is in fact your purely singular subjective opinion of what works and has no relevence. Without any established objective means of quantification, I have to assume that "accurate" will best portray any "depth" that is present in the recording. Any modification to accuracy to resolve a personal subjective impression of yours, or anyone elses (including mine) would not be something that I would ever do.
I like the CBT concept though. The one that makes sound, that is. It has many very desirable characteristics. Would love to hear one some day.
CBT only makes sense if you believe that very early lateral reflections are a good thing. If, as I do, you believe the opposite then CBT has some very bad characteristics. It is Constant Beamwidth only in the sense of being omni laterally. Horizontally it has no directivity control at all.
I do not believe that is true. We have discussed this before. Or perhaps we don't agree on the terms.
A source that is so narrow that within its usable bandwidth its polar response is 360 degrees is NOT "Controlled Directivity" IMO. It is "default" directivity, there is nothing "controlled" about it. "Controlled" to me means something < 360 degrees that is maintained throughout the useful bandwidth. Is a monopole "Controlled Directivity"? No, it's just that it is so wide that it does not vary because 360 degrees is as wide as is possible.
Even Don Keele gives me this, even though he doesn't advertise it. He says that the "constant" refers to the vertical control - and I give him that. But those characteristics are not what I am looking for.
And we both agree that an circular array could do both (think torpedo head!)- but those have so many other problems and cost associated that I wouldn't want to go there.
What is elegant about Don's design is how he does the shading passively - that is impressive, although not really new, passive Bessel shading has been used for decades.
Even Don Keele gives me this, even though he doesn't advertise it. He says that the "constant" refers to the vertical control - and I give him that. But those characteristics are not what I am looking for.
And we both agree that an circular array could do both (think torpedo head!)- but those have so many other problems and cost associated that I wouldn't want to go there.
What is elegant about Don's design is how he does the shading passively - that is impressive, although not really new, passive Bessel shading has been used for decades.
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Do you need an objective definition to design for it? I don't. (..note I'm not saying I can reach any sort of precision, but virtually anyone can tell "more" from "less" with enough of a difference between "more" and "less".)
Depth as a definition doesn't need "enhancement" - its common meaning is obvious in this context for which it is being used. Your use of it just now emphasizes this.
While we could go into more detail, it's not really necessary or productive.
Objectively I can in-fact alter the freq. response in the manner stipulated to increase the apparent depth of any standard loudspeaker. Nor would I suggest it if I was the only one who could do so, or the only one who has ever heard this done, or was the only one that had ever done so.
Anyone can. Many have heard this effect. Many have done so. Again though, not terribly useful because doing so creates other problems. My mention of this is only an example of objectivity in designing for "depth". (..it's something I can see on a measurement and change, with a resulting increase in the portrayal of depth. THAT's an objective alteration.) As far as relevance - that's it.Everyone knows what we mean when we mention "depth" in audio. I'm not asking questions about precisely how "deep". As far as accuracy is concerned it's a given: what's on the recording.
The question posed however is far more basic - referring to more depth rather than less depth with respect to imaging. "Pancake flat" results in your classic "ping-pong" stereo with all images "bunched" between the loudspeakers without extending reward beyond the loudspeakers, regardless of the recording. That's the extreme, work out from there.
Again:
What are you doing *objectively* that expressly accounts for an improved subjective depth perspective from your designs?
Or, are your results (without disparagement) somewhat lucky in this regard?
Or, do you in fact use subjective evaluation to some degree to obtain an improved subjective depth perspective?
That's because you believe that your subjective opinion is what other will also perceive. I don't. And I don't accept anything that is based on evidence like that. So, yes, I DO need something objective or something shown in a VALID subjective test that indicates a relationship, otherwise its just the same old "it sounds good to me" - smoke and mirrors; mystic relationships; magical formulas (and now I remember why I don't respond to your posts.)
Don't forget the phenomenon of adaption, which includes room acoustists and the resulting ability to hear through the room.
While I would agree that a monopole is not controlled directivity because of its default, it is constant directivity anyway.
And you may also argue that it becomes controlled directivity if the designer picks the radiation pattern deliberately. So he controls the intended directivity.
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This is incorrect. The fact is that in most rooms you will have less early reflections from a CBT speaker then a waveguide/horn. You avoid vertical reflections with CBT and they arrive after all earlier the horizontal. So you have a less total of early reflections.
Sure, with the waveguide you avoid the nearest sidewall reflections with enough toe-in, but not from the opposite wall. And with much toe-in it should also be notified that dampening the opposite sidewall reflections is more difficult because of the sharp angle.
You only have a little less sidewall reflections with waveguide/horn then a CBT. But since there are more vertical early reflections, the total will be more in most cases.
Gedlee also seems to overlook the importance of a uniform response. While the CBT does the dispers wide, it does it extremely uniform and is almost flat out to 90 degrees in every height. An omni isn't able to do that by the way, only at a certain height. The result is less colouration from the room, since the off-axis response is so close to the on-axis response. If one choses to have lateral contribution or not is up to the listener.
With a waveguide, you have a wide dispersion at some freqeuncies, they start to narrow at around 800 Hz and get's even narrowere higher up. So the reflective energy will not resemble the direct sound very well. Side wall reflections thus may interfere destructively with the direct sound. You have to look at the total energy level and not just the amount of early reflections. And vertically the response from a CBT is besically perfect, while most waveguides and horns have a lot of irregularities. A better and more complex horn can look better, but will have some beaming and broadband absorption is necessary.
But again, I believe both CBT and waveguide/horn have their place in different environments. Under ideal conditions there is not doubt in my mind though. The CBT is a better speaker becasue of a more uniform response and controlled directivity lower in frequencies. The result is a flatter response. And it's incorrect to say that you get more early reflections with a CBT. I believe it's the opposite for most rooms.
Here's an ETC with CBTs in a room with no vertical treatment. You would not see this low amount with early reflections with a waveguide in the same position. There's a sloping ceiling by the way behind the mic that is sending energy back. With a flat and heigher ceiling this would look much better. .
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I may not have explained myself clear enough. I was just trying to say I doubt there is ONE speaker, ONE room, perfect for ALL types of music. I believe you have to make a choice at one stage. The AS broadening from dipoles works very well for hall enthusiasts, not so well maybe for electronica hardcore fans.. I wasn't really thinking of perfect waveform reconstruction anyway..
Ambiophonics would be good indeed, if all recordings were done with a sphere microphone at the best seat. But what to do with the million others?
Talking of recording techniques, which book would be "the one" to read on the subject?
......I think we can all agree that it's time to retire from this forum
The funny thing is.....it's possible right now!
Hmmm......
I've been thinking that too. Kind of give up most of what I am doing and start collecting and listening to more music rather than fiddling with equipment!
Just bought a Behringer 3030A to see what all the fuss was about. Did several " no I don't need it / but I only want to check it out "......bouts in my brain. Lasted a full 4 weeks ......but I caved in finally !
Yeah , it's great for it's price and better than many at much higher prices !
Also confirm that it definitely needs a sub !
It's diffucult to discuss against any who are saying they prefer the backwave from the frontwall from dipoles. The idea that it get's you closer to the recording by doing it is however wrong IMO.
You can never get closer to the real by adding comb filter and reflections from the room.
I don understand that thought though. You feel you miss speaciousness and natural ambience from the mix, and want to add this. The problem is that you also end up partially wrecking areas lik clarity, intelligibility, loacalization and tonality.
Personally I prefer a combination of correct and sharp image with a diffusive backwall with it's enlargement and envelopment. Best of two worlds IMO. And it's not intruding on the recorded signal if the diffusion arrives late enough.
You can never get closer to the real by adding comb filter and reflections from the room.
I don understand that thought though. You feel you miss speaciousness and natural ambience from the mix, and want to add this. The problem is that you also end up partially wrecking areas lik clarity, intelligibility, loacalization and tonality.
Personally I prefer a combination of correct and sharp image with a diffusive backwall with it's enlargement and envelopment. Best of two worlds IMO. And it's not intruding on the recorded signal if the diffusion arrives late enough.
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It's up to you if you want an accurate and critical listening environment or not. I wouldn't call accuracy pre-psychoacoustic era. I've yet to hear anyone who didn't enjoy greatly a well designed RFZ room. I hear plenty who don't enjoy either a contribution from frontwall or sidewalls though.
We don't hav a lot of researches of different types of room treatment and speaker arrangements when it comes to preferences. We do however know a lot about accuracy and the effect of early and later arrival reflections.
Toole's researches are interesting, but doesn't necessarliy tell us that much. First of all they were not very conclusive. It varied with the music material. Secondly, the room and the way they were treated obviously would have an effect. It's not exactly a shock that several preferred some lateral reflections in an anechoic chamber. The speakers may also have had an effect.
As far as I know Toole never conducted the researches in a LEDE/RFZ type room with diffusive energy from behind. I wouldn't be surprised if the result would have been different then.
Either way, it's up to the listener what to choose. Very few get to compare different arrangements and often end up defending what they have already chosen. That doesn't take us any further.
I do agree with that, no argument. But the CBT has a changing polar pattern over its length. Wide at one end, narrow at the other - thus it has "some" directivity control.
Dipoles have restrictions, as long as you keep them in mind, they do not behave as badly as the dark legend says and goes on, and on, and on...
Sure, "critical listening".. But do you work or relax with music? Is RFZ the ultimate tool for recordings with natural and/or high TR? I doubt it, but as I am open minded, I may try it later this year. But to be honest, I don't want to be limited to 60 deg scenes.. as accurate a window of the event it can get, it's just not realistic.
The room has always been seen as a "recording offender", maybe it isn't exactly that bad and it can be used to our advantage..
Sure. I don't think the backwave from the frontwall from electrostatics sounds bad. Personally, I'm quite sure I would dampen it, but that 's not the same to say it's not tolerant and can sound ok. It's out of phase though.Dipoles have restrictions, as long as you keep them in mind, they do not behave as badly as the dark legend says and goes on, and on, and on...
Sure, "critical listening".. But do you work or relax with music? Is RFZ the ultimate tool for recordings with natural and/or high TR? I doubt it, but as I am open minded, I may try it later this year. But to be honest, I don't want to be limited to 60 deg scenes.. as accurate a window of the event it can get, it's just not realistic.
The room has always been seen as a "recording offender", maybe it isn't exactly that bad and it can be used to our advantage..
It's the same with lateral reflections. Personally I don't want it. At least not in narrow rooms. I don't however find it a major hindrance of enjoying music as long as the horizontal power response is good. You do get more spaciousness and a wider scene that way.
Subjectivally, I find LEDE/RFZ very enjoyable for listening and relaxing. More then anything else and I have tried about every arrangement that's possible. I have had diffusors on sidewalls, ceiling, frontwall, reflective sidewalls etc. Been there done it. But that's me and I'm not going to pass on my preferences to everyone else. Try it for yourself and see what you like.
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Yes exactly true. Still the listener preference should be the main criteria when one is designing home sound system for himself.