Interesting that the flooder increased reverberation time as far out in time as 20 ms at only -6 to -10 dB, beyond the integration time for "single event" perception. The reverberation at -10 dB would sound half as loud as the original signal.
No doubt that would increase "spaciousness" and reduce detail.
Also of note, the first (ceiling) reflection of your speaker was stronger than the direct sound at high frequencies due to the narrowing HF pattern.
The speaker I tried in the FCUFS configuration had wide enough HF pattern where my hearing still localized it to the floor, rather than the ceiling.
Art
It also depends on the listener's/measurement position relative to the speakers and the various boundaries..
BTW, good post!
Nice to have something that really expresses genuine issues with a floor flooder. 
(..as opposed to the typical: "it generates more reflections" and "more reflections are bad".)
It can also be noted that because the speaker was placed beside the wall (as recommended) there is also reflection from the nearby wall causing combing to the the direct sound.
And, due to the same reason there is also combing in the ceiling reflected sound (altough different comb pattern due to different path length difference).
The speaker should have such a high directivity there would be practically no reflection from the beside wall. If one likes to remove the combing, that is.
I'm not sure about the perceptual effect of the comb, though.
And, due to the same reason there is also combing in the ceiling reflected sound (altough different comb pattern due to different path length difference).
The speaker should have such a high directivity there would be practically no reflection from the beside wall. If one likes to remove the combing, that is.
I'm not sure about the perceptual effect of the comb, though.
maybe I have posted this before
That is not floor coupled
But I now it will work very well. How do I know, because I have tried something very similar.
I posted this before, too, but cannot remember which thread
Nevermind, as this thread is famous for double posts here is picture of my earlier experiment.Floor level dipole and upwards tilted tweeter horn at ear level:
An externally hosted image should be here but it was not working when we last tested it.
why no doubt "reduce detail"? What´s the psychoacoustic mechanism?
Are You sure? Do You know the radiation pattern of Elias´ test FCUFS?
The reduction in detail is a hold-over of two principals from large room acoustics..
1. Excessive Reverberation in time (and amplitude) perceptually "blunts" transients in a "masking" effect. However, the intensity and delay of those reflections and their bandwidth, at that "threashold" are relatively unknown in a small room context. In fact through-out the relevant chapters in Toole's book (particularly combing chp. 9), depending on the delay, intensity, passband, and distribution - they may actually improve detail perception in some respects.
2. First Reflections and the creation of "echos" - with doesn't apply here.
2-way for Elias's experiments. It might matter when comparing subjective comments (Elias & weltersys), but -
Doesn't really matter on an objective basis - even most 1" tweeters will have a fair bit of loss in pressure that far off-axis above 5 kHz (assuming a modest size baffle). Additionally, because the loudspeaker's placement next to the side-wall - I've a feeling that provided a fair bit of added intensity at high freq.s to the reflections (..transition from ceiling to wall and vice-versus).
That was when I didn't understand your wavelets sufficiently.Looks like I posted them in August 2010, so it was three years ago
With those pics I can almost hear what I see. Every fat reflection above 4 ms robs detail and enhances ASW. There are lots of them in the flooder response. Maybe graaf is fond of that - I'm certainly not.
Rudolf
Yes, that's what it is. The effect of ASW. Some like it (a lot). In my opinion it should be a property of the reproduction technique, not a property of speaker/room interaction if the reproduction of a wide range of auditory spaces is the goal. ASW created by the room can not be switched off. If all one is interested in is ASW then flooding the room with energy will create it. As a side effect reverberation times will be way too high for a detailed/transparent presentation which I like much better than a spacious but very garbled wash of sound.
What is the true benefit of avoiding floor reflection ? What's the point of floor coupling ?
Reading Toole's book with a great detail we can come to some peculiar conclusions.
Here from Chapter 6.2.1 p 84-85: (emphasises mine)
It looks like, maybe not surprisingly, the perceptional effects of floor reflection occur in high freq range, and a carpet is sufficient to diminish it below the threshold.
So, we don't need floor coupling
- Elias
Reading Toole's book with a great detail we can come to some peculiar conclusions.
Here from Chapter 6.2.1 p 84-85: (emphasises mine)
It looks like, maybe not surprisingly, the perceptional effects of floor reflection occur in high freq range, and a carpet is sufficient to diminish it below the threshold.
So, we don't need floor coupling
- Elias
any references for that Rudolf?
preferably references where fat reflection is defined, and where the 4 ms threshold is substantiated and explained
What is the true benefit of avoiding floor reflection ? What's the point of floor coupling ?
Reading Toole's book with a great detail we can come to some peculiar conclusions.
Here from Chapter 6.2.1 p 84-85: (emphasises mine)
It looks like, maybe not surprisingly, the perceptional effects of floor reflection occur in high freq range, and a carpet is sufficient to diminish it below the threshold.
So, we don't need floor coupling
- Elias
not too fast to the conclusion
remember what says Mr Lyngdorf who was a member of Bech's test panels:
so we have here "the effect was not large" vs "That is what makes the speaker sound like a radio and not like the actual event"
as to the objective and abstract-theoretical question of what's the point of floor coupling - this was discussed thoroughly many times earlier in this thread
as to the subjective question of is the effect large or not all I can say is that what I can hear corresponds with what Mr Lyngdorf says.
Perhaps it is that not all of us here have equally acute hearing and equally demanding taste for realistic sound
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reverberation times is a wholly separate issue from the pattern of early reflections
FCUFS only creates a pattern of early reflections different from a conventional system
the issue of reverberation times which is a matter of general room absorption coefficients has nothing to do with it
please do not misinform people Markus
graaf;
Please clarify subjective crap statement "makes speaker sound like a radio". Radio can only be heard if it has a speaker. What kind of radio was Lyngdorf referring to? What kind of speaker was it playing through? What kind of listening environment is radio/speaker playing in?
How about some real reference from you to bring this rodeo up to date, such as current speakers, room conditions, speaker locations, and some posted wave files of measured impulse responses at listening position. This way the inclined members with desire to explore the topic have something to work with besides your endless blather.
References for what? I have "looked" at the early reflections in my room with my ears and my microphone. I enhanced and attenuated the reflections - every single one for itself. That has given me a gross overview of the relations between changes in diagrams and my acoustic impressions. There is no 4 ms "threshold" of course and no universal definition of "fat". It's up to every single person to find his personal thresholds and limits. But you need some sort of measurements to compare with others. Sadly you don't show any.
Rudolf
to illustrate my point let me quote from one of earlier posts in this thread:
it may be that You cannot understand what I am talking about because You have never heard anything like that
You can send an e-mail to Mr Lyngdorf
You mean members like You?
to compare what? personal thresholds? what for?
c'mon Rudolf! please! Your "Every fat reflection above 4 ms robs detail" is either science or just another kind of subjective crap statement (see: Barleywater, above), isn't it?
Sadly you don't show any.
Rudolf
sadly others have shown and it changed nothing in the discussion because measurements are just meaningless in themselves that is without theoretical interpretation
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