Hi,
In the pic (in the previous post), I saw 4 channels plus subs. Is that right? The wides can't be clearly seen. Are they widerangers or.... ?
What's the overall setup (channel distributions)? Would you please share more? Sorry if this has already been brought up before.
Thanks a lot🙂
With my Carlssons I don't measure other reflections that are anywhere as high in level as the ceiling reflections. I tried crossfiring setups (speakers facing eachother) with several fullrange drivers. IMO a mess and not at all similar to realistic imaging. But such a setup is extreme and not comparable to what Earl does.
Toole has shown that reflections are perceptually grouped: "[...] when the authors conducted subjective tests in an anechoic chamber, they found that the sequence of three low-level refl ections and the large single refl ection were “almost equally loud.” The message here is that if we believed the impulse response measurements, we might have concluded that by breaking up the large refl ecting surface, we had reduced the audible effects. This is one of the persistent problems of psychoacoustics. Human perception is usually nonlinear, and technical measurements are remarkably linear."
I don't know how to measure and map this perceptually in a meaningful way but this is definitely something that has to be done one day in psychoacoustics.
Crossfiring speakers will create loud reflections from the opposite wall (e.g. L speaker creates louder reflections coming from the right). A high directivity design increases the amount of energy that is radiated towards the opposite wall. The result is even louder reflections. Here's data from my room:
An externally hosted image should be here but it was not working when we last tested it.
In my experience this can override precedence and shift sounds towards the opposite side. The sound stage becomes smaller.
You should see (or hear) a similar effect with your Carlsons radiating a lot of energy towards the ceiling. When I tried such a setup the image was shifted in height. Even the rather small height difference between center and wides in the test setup above shifts the sound upwards.
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But with crossfiring you should get little better direct to reverbant ratio, Markus. Isn't it?
It is not necessarily bad. It implies to me that if crossed too much - too small soundstage, too wide - too big soundstage. So, there should be on optimum for given speakers (omnis excepted)
I do not believe the concept of direct to reverberant ratio is very useful in acoustically small rooms. There is no diffuse sound field, it's highly directional. Level, delay, number, angle and spectrum of reflections is the key. We just don't know how to relate this to sound perception yet.
This solely depends on the speakers directivity and the room.
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I did not mean D/R ratio in exact sense. You are right. Seems to me that there is no consensus even about measures. A year ago I visited friend. I was listening in a very dead and a very small (12sqm) room. Soundstage was elevated. Thought about it later and got three possible answers. Low IACC (I know, you don't ... but Toole writes about it 🙂 ), reflection from ceiling difusser in otherwise dead room or strong reflection from the back wall (listened near the b.w.). Choose one, two or three.
Thanks for sharing. I missed those 2 small speakers in the middle 😱
In previous post(s), I remember you said it'd be harmful. So, did you try any other configuration? For example, make the wides upfiring (quasi-omni in horizontal plane), or reduce the signal to L-R / R-L ?
In previous post(s), I remember you said it'd be harmful. So, did you try any other configuration? For example, make the wides upfiring (quasi-omni in horizontal plane), or reduce the signal to L-R / R-L ?
Those are two 3" fullrange drivers wired in series.
The center setup doesn't use L or R speakers so the problem doesn't arise. The wides were at 60° and got the full L or R stereo signal (which can be varied in level, delay, EQ), no difference signal was used. I did point them to the listening position to minimize reflections.
An externally hosted image should be here but it was not working when we last tested it.
Was playing around with this idea for a while. ER18RNX with a neo tweeter. As in initial guestimate profile curves match those calculated for a dome tweeter waveguide, but wrapped around the central axis. The woofer is inverted. Pretty transparent basket on that one.
Would be very easy to make on a wood lathe.
More flights of fancy ideas than time to mess with them I guess. Probably a good thing.
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An externally hosted image should be here but it was not working when we last tested it.
Was playing around with this idea for a while. ER18RNX with a neo tweeter. As in initial guestimate profile curves match those calculated for a dome tweeter waveguide, but wrapped around the central axis. The woofer is inverted.
Would be very easy to make on a wood lathe.
More flights of fancy ideas than time to mess with them I guess. Probably a good thing.
Yes, the extreme "toe-in" or "crossing in front" scheme increases the similarity of the signal reaching each ear. (..my IACC response earlier.)
On the other hand radiation toward the ceiling (*generally) and it's reflections do not behave in the same manner. It is not increasing the similarity of the signal to each ear because their isn't any real change horizontally. Moreover it also is rarely as distant (loudspeaker to ceiling) as loudspeaker to opposite wall. I would not expect (nor have experienced), a change in apparent imaging height from a ceiling reflection.
I have however experienced a change in apparent imaging height from a change in the loudspeakers radiation pattern (and also changing the baffle's characteristics). For instance "tilting" a loudspeaker backwards from a frontal position tends to increase imaging height.
I've also experimented with 3 channels, and yes - making the L & R speakers higher does effect height. Again though, these are direct sound sources.. not reflections.
*note on "generally*. IF however you have a ceiling that is "pitched" i.e. /\, Then you are increasing the similarity of the signal reaching each ear (though still to a lesser extent).
Things I've noticed with some of the topics discussed here.
1) crossfiring narrow pattern speakers definitely produced a spacious sound, but I lost my pinpoint image depending on a couple factors. In a big enough room, I'd think this would be optimal, but I'll likely never get to try that out. I attributed this to my small room and it definitely helped to absorb those reflections as much as possible. These gave a sense of great dynamics and the best of both worlds of image and space when sitting closer. Slight head movements became a problem then. Further away they became more vague.
2) wide pattern speakers didn't give me any issues locating the source really, but made everything sound very large and also detailed as can be and had a very spacious sound as well. Perhaps a bit vague image, but not in an intolerable or unenjoyable way. Just not as spacious as the crossfired narrow patterned. Literally thought things were broken b/c I was hear distortion on recordings. Dr. Toole's "second look" is a likely culprit.
3) medium pattern. This is my favorite. All things in moderation. Add surround sound, intelligent treatment, and a room EQ and love life.
A new system in the works incorporating all I've learned so far.
Dan
With enough time, positioning, EQ and treatment, bliss is achievable from many methods and price ranges.
1) crossfiring narrow pattern speakers definitely produced a spacious sound, but I lost my pinpoint image depending on a couple factors. In a big enough room, I'd think this would be optimal, but I'll likely never get to try that out. I attributed this to my small room and it definitely helped to absorb those reflections as much as possible. These gave a sense of great dynamics and the best of both worlds of image and space when sitting closer. Slight head movements became a problem then. Further away they became more vague.
2) wide pattern speakers didn't give me any issues locating the source really, but made everything sound very large and also detailed as can be and had a very spacious sound as well. Perhaps a bit vague image, but not in an intolerable or unenjoyable way. Just not as spacious as the crossfired narrow patterned. Literally thought things were broken b/c I was hear distortion on recordings. Dr. Toole's "second look" is a likely culprit.
3) medium pattern. This is my favorite. All things in moderation. Add surround sound, intelligent treatment, and a room EQ and love life.
A new system in the works incorporating all I've learned so far.
Dan
With enough time, positioning, EQ and treatment, bliss is achievable from many methods and price ranges.
Dan,
Can you put some ballpark coverage angles to "narrow," "wide," and "medium" pattern?
I ask because I suspect that opinions may diverge quite a bit on what those terms mean.
yes.
CLS has also done this with eminence compression super tweeters.
-my experience..even under the best of circumstances (i.e. good "reflective" profile), there is still treble loss that needs correction.
The other limitation is high-pass filtering and integration with the mid-range driver.
It's particularly interesting to move the two sources apart, where you lower the height of the bottom driver and raise the height of the top driver. 😉
Ah ~ mine is a bad example 😱
Look here for a better omni from dome tweeter:
HTGuide Forum - Raal Omni Discussion
😀
Look here for a better omni from dome tweeter:
HTGuide Forum - Raal Omni Discussion
😀
