Are you sure about that? I get what are saying technically, "balanced" but lets be clear on if its an "issue"
An analogy I could use is FR.... you are saying that because one part of FR stays smooth, for a longer period than another part .... that, thats, an issue. The room taking over is a detriment to me, so the more of the direct sound that dominates, at any given distance of listening, is, a win. It is only relative to in comparison to other options, which are all tied together because most every system will be omnidirectional eventually, given they are full spectrum.
What is the highest DI for a 1.4"-2" waveguide crossing at the typical XO
If I have a High ranking DI in terms of exponential horns, my DI might be
The fault in direct/room of rising DI is subjective. Also still a fault. As I stated in my threads recent post. The DI of these horns are changing smoothly 1db per octave in my case to the best of my knowledge and 3.5/db in the case of a Round tractrix horn with 160ish f6.
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^Hi,
I encourage you find where the audible critical distance in your room and speaker is, where stereo impression changes. Further away from this critical distance and you will hear mostly room sound, which approximates power response of your speakers. Listening closer than the critical distance you'd be listening direct sound mostly, not much of your room except to give some feel of envelopment. Difference of these two responses is the DI, and the more DI deviates from flat the more the direct sound deviates from power response.
If speakers have strongly rising DI, the sound would be dark when listening far away unless power response was equalized to compensate. Its the power response you listen mostly in the far field. With less rising DI the room sound could already be nice without compensating for power response. Likewise, listening on the close proximity then the envelopment could be dark, or worse you might sit at a distance where only high frequencies feel close and lows far away. This might be fine for home hifi but if you are doing sound work where you probably want it all even, hence flatter DI would be my chosen. Try it, add global "room reverb" to some track and add low pass filter to it at some arbitrary frequency. This would be worst case demonstration how in your face highs and roomy lows sounds.
Trick is to always listen close distance, close enough, no matter what the DI is, just move your chair. Its not just high frequencies you need to be close, but some bandwidth, say from 700Hz up. So, all that matters is that DI at 700Hz is sufficiently high so that you get the critical distance to your practical listening distance. DI would rise with frequency but the less it rises the more similar listening axis and power response are and the more uniform the sound ought to be, at any distance from the speakers.
This is by reasoning only based on listening one system with a particular DI shape, I've got no other data to augment than my perception and what I've reasoned based on that. If you find and listen the critical distance yourself and use your perception of the close sound and far sound as a launch point and do reasoning why things sound as they do you'd likely come to same conclusion. Our rooms and speakers and acoustics vary, also expectations and what is meaningful and what is not, so there is probably some wiggle room.
I encourage you find where the audible critical distance in your room and speaker is, where stereo impression changes. Further away from this critical distance and you will hear mostly room sound, which approximates power response of your speakers. Listening closer than the critical distance you'd be listening direct sound mostly, not much of your room except to give some feel of envelopment. Difference of these two responses is the DI, and the more DI deviates from flat the more the direct sound deviates from power response.
If speakers have strongly rising DI, the sound would be dark when listening far away unless power response was equalized to compensate. Its the power response you listen mostly in the far field. With less rising DI the room sound could already be nice without compensating for power response. Likewise, listening on the close proximity then the envelopment could be dark, or worse you might sit at a distance where only high frequencies feel close and lows far away. This might be fine for home hifi but if you are doing sound work where you probably want it all even, hence flatter DI would be my chosen. Try it, add global "room reverb" to some track and add low pass filter to it at some arbitrary frequency. This would be worst case demonstration how in your face highs and roomy lows sounds.
Trick is to always listen close distance, close enough, no matter what the DI is, just move your chair. Its not just high frequencies you need to be close, but some bandwidth, say from 700Hz up. So, all that matters is that DI at 700Hz is sufficiently high so that you get the critical distance to your practical listening distance. DI would rise with frequency but the less it rises the more similar listening axis and power response are and the more uniform the sound ought to be, at any distance from the speakers.
This is by reasoning only based on listening one system with a particular DI shape, I've got no other data to augment than my perception and what I've reasoned based on that. If you find and listen the critical distance yourself and use your perception of the close sound and far sound as a launch point and do reasoning why things sound as they do you'd likely come to same conclusion. Our rooms and speakers and acoustics vary, also expectations and what is meaningful and what is not, so there is probably some wiggle room.
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Untrue from the start. AT HFs the ear processes the direct sound independent of any room reflections (it's very fast) and hence it is not "mostly room sounds". We hear the direct sound as if it's anechoic followed by spaciousness. AT LFs we hear almost exclusively room sound.
These misunderstandings seem to be everywhere.
Thanks, info about such things is not floating around and never knew to look for it, but now I can 
So, if listening axis has ~flat frequency response, but hearing difference in sound with two different DI systems would mean sound of the spaciousness must have changed? And it seems to change with the critical distance. Do you know what frequency bandwidth is responsible for the change? it must be between low frequency room sound and high frequency anechoic sound, right?
So, if listening axis has ~flat frequency response, but hearing difference in sound with two different DI systems would mean sound of the spaciousness must have changed? And it seems to change with the critical distance. Do you know what frequency bandwidth is responsible for the change? it must be between low frequency room sound and high frequency anechoic sound, right?
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I believe it was Tonmeister.ca that mentioned in his website of a recording in a large hall, one with mics off directly after the direct sound and another many milliseconds later. Only the latter had the spaciousness of the hall.
I think it's not "anechoic" at HF. You still hear both "streams". At LF you just can't differentiate. At HF you can - there's plenty of time between the direct sound (the first arriving) and the reflections in terms of periods. At least that's how I understand it. And it somehow sounds the most natural when the reflections timbrally match the direct sound. Up to what frequency is it important? I don't know. Some say 8 or 10 kHz, probably not much above 15 kHz.
Interestingly, not very often is the directivity of the ear itself taken into consideration. It must be significant at high frequencies - I'd expect even more sound to be received via the reflections than directly from the (frontal) source at the very high frequencies. It's all so complex.
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Yeah, I'm working from the perception and write from that perspective, whether room seems to affect the perception or not. I do not have knowledge what actually happens with hearing system, all I know there is the shift with listening distance which sounds like influence of local room disappears and wrote that it would be the mostly direct sound, while far away it would be mostly room sound. I understand Geddes pointing out there is always direct sound and always room sound, a technical perspective on it.
I'm sure Geddes knows more about the subject, hopefully he returns with more info about it
It is interesting subject as its quite easy to hear influence of room included, or not. Or perhaps when the room makes bad influence and when its good influence, I do not know what the correct wording would be. Since DI indicates level of room sound it must relate to the phenomenon, quality of room influence.
It certainly seems like when D/R ratio is sufficiently high there is clarity and room influence seems gone and nice, and when its too low sound seems hazy, especially stereo phantom center. Griesinger papers indicate that when brain can lock in to sound harmonics there is the clarity as the direct sound and background sound get their own neural streams, and when it cannot do this separation there is only one stream, the irrelevant noise brain doesn't consider important, the room sound Well, just trying to stitch pieces of information together and speculate on it in hope to encourage discussion.
I'm sure Geddes knows more about the subject, hopefully he returns with more info about it
It is interesting subject as its quite easy to hear influence of room included, or not. Or perhaps when the room makes bad influence and when its good influence, I do not know what the correct wording would be. Since DI indicates level of room sound it must relate to the phenomenon, quality of room influence.
It certainly seems like when D/R ratio is sufficiently high there is clarity and room influence seems gone and nice, and when its too low sound seems hazy, especially stereo phantom center. Griesinger papers indicate that when brain can lock in to sound harmonics there is the clarity as the direct sound and background sound get their own neural streams, and when it cannot do this separation there is only one stream, the irrelevant noise brain doesn't consider important, the room sound
Well, just trying to stitch pieces of information together and speculate on it in hope to encourage discussion.
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Well, yeah, at least the quality of it likely changes. I've had my speakers at various locations and distances to boundaries in the same room and the critical distance where perception shifts seems to stay the same so I've attributed it to D/R and not for example to some singular early reflections. I'm using tape measure so its not just eye balling the listening distance but of course could contain some error and unknowns affecting. Distance from ear to speaker seems to be roughly constant for the perceived transition.
Certainly it could be anything, as this is just one system in on room. I'm hoping more people would play withit, find the audible crotocal distance and write about it to get more data
Certainly it could be anything, as this is just one system in on room. I'm hoping more people would play withit, find the audible crotocal distance and write about it to get more data
It would be great if you could experiment also with some more beaming horn in this regard. I think I prepared one here as well but you can easily make one with Ath anytime.
ST280E: https://at-horns.eu/ext/ST280E.zip
- It's a very smooth, moderately high-loading 1" horn. Should give great Clarity
ST280E: https://at-horns.eu/ext/ST280E.zip
- It's a very smooth, moderately high-loading 1" horn. Should give great Clarity
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Yes definitely have to try one, unfortunately I don't have printer so it takes time to get to that. Plan is to get new waveguides printed, perhaps after few days of freedom to get time to prepare an order.
By the way, its possible to arrange speakers so that the sound gets inside head like with headphones, this is very weird, room seems to be removed completely like with headphones. My listening triangle is currently setup into one corner of living room in such way that speakers, listening position and room corner forms a square. Speakers are on-wall. There is small sofa on the corner between the speakers and sitting there head is between the speakers and headphone feel can be achieved with toe in. Toe speakers out, basically to same direction I'm facing, to the room, and perception seems to shift out of head, very roomy sound. More over stereo image seems to be very high up which I attribute to lack of floor reflection while reflection on the ceiling is there. Early floor reflection is very different as sofa is there between ear and speaker, very different path length and acoustic properties compared to normal listening situation with carpet on the floor. All kinds of fun stuff listening I'm so excited
So, as you say there is high possibility multiple things are at play that attribute to all kinds of perceived phenomena with stereo phantom center. Directivity of the system, acoustics of the room, "directivity" of hearing, or lumped just as hearing system, and relationship between all of them, which all depends on frequency and distances and so on Not exactly simple so its very much fun to play around with the critical distance transition as that seems to be such a beacon, seemingly simple phenomenon like a light source in darkness
By the way, its possible to arrange speakers so that the sound gets inside head like with headphones, this is very weird, room seems to be removed completely like with headphones. My listening triangle is currently setup into one corner of living room in such way that speakers, listening position and room corner forms a square. Speakers are on-wall. There is small sofa on the corner between the speakers and sitting there head is between the speakers and headphone feel can be achieved with toe in. Toe speakers out, basically to same direction I'm facing, to the room, and perception seems to shift out of head, very roomy sound. More over stereo image seems to be very high up which I attribute to lack of floor reflection while reflection on the ceiling is there. Early floor reflection is very different as sofa is there between ear and speaker, very different path length and acoustic properties compared to normal listening situation with carpet on the floor. All kinds of fun stuff listening I'm so excited
So, as you say there is high possibility multiple things are at play that attribute to all kinds of perceived phenomena with stereo phantom center. Directivity of the system, acoustics of the room, "directivity" of hearing, or lumped just as hearing system, and relationship between all of them, which all depends on frequency and distances and so on
Not exactly simple so its very much fun to play around with the critical distance transition as that seems to be such a beacon, seemingly simple phenomenon like a light source in darkness
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- I've quickly tried an "athexed" version of the ST280E. Here's the performance. Note the DI@20deg - it's almost ruler flat above 5 kHz. This means that when listened at 20deg off-axis, the timbre of the (overall) reverberant sound will match the timbre of the direct sound almost perfectly (not individual reflections but on average it will, if the room is neutral). It may only need an EQ to elevate the HF a bit, as it would probably sound too dull as it's shown.
(To extend the flat DI@20deg lower, it would just need to be bigger.)
(To extend the flat DI@20deg lower, it would just need to be bigger.)
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Here, found paper by Griesinger for stereo loudspeaker context http://www.davidgriesinger.com/Acoustics_Today/AES_preprint_2012_2.pdf
I'm seriously considering sand printing of the hexagonal parts, individually, to be glued together additionally by some damping layer.With a sand print it would be faster
Sandhorns in black.
I believe they could print 12 pieces at once (if not more) without any trouble, to make pretty large horns without all the issues with large parts (mainly the risk of breaking during manipulation or transport). I would also make it a bit more robust (heavier) this time.
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This is quite true, as I have discussed before. It's a valid test to take a set of speakers and find the critical distance where this happens. But it is another thing to compare two different speakers with different DI as many many things could have changed.