this <6 ms front wall reflection is not unavoidable, is anything wrong with the sloped baffle (acting like a virtual tilted wall) solution that I have proposed (see the scheme earlier in the thread)?
What I find wrong with that listening arrangement is the direct sound is still coming from below, which would be representative of small yapping dogs or crying babies gathered at the floor/sloped baffle juncture, but the wrong locational cue for the type of program material I normally choose to listen to.
Could you post a photo of the sloped baffles you currently employ in your listening room, or were they just a proposal to eliminate the early wall reflections you are hearing with your present set up?
Seems the baffle sloping out to the floor would be a trip hazard.
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And by the way, the majority of livingrooms in Denmark have hard floor -either stone or wood, and the ceilings are completely flat.
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the topic has been thoroughly discussed in this thread - the soundstage is NOT abnormally low, the sound is NOT coming from the floor
why? here is why:
it is because vertical localisation relies on two cues:
1) the time domain cue that is the floor reflection which is effectively absent in the case under consideration
2) the frequency domain cue that is HRTF which is neutralized in the case under consideration because there is roughly equal amount of HRTF-related high refequnecy content coming BOTH from below - in the direct sound and from above - in the first ceiling reflection so both HRTF vertical cues effectively neutralize each other!
Joachim Gerhard refers to his own and others experience with the Snell Type 1:
http://www.diyaudio.com/forums/full-range/162827-mpl-33.html#post3478143
None of those people is commenting about sound coming from the floor. It is not mandatory that we hear sound coming from the direction of its source in each and every case.
Joachim Gerhard refers to his own and others experience with the Snell Type 1:
http://www.diyaudio.com/forums/full-range/162827-mpl-33.html#post3478143
None of those people is commenting about sound coming from the floor. It is not mandatory that we hear sound coming from the direction of its source in each and every case.
thanks Rudolf
It's pointless to reply..
In the future if you see his posts doing that sort of attacking to "win" an argument - jut click on the report post button at the lower left of the offending post. At some point the mod.s should step-in and remove it.
Sometimes you just have to help with cleaning-up the trash that's abusive.
the topic has been thoroughly discussed in this thread - the soundstage is NOT abnormally low, the sound is NOT coming from the floor
why? here is why:
it is because vertical localisation relies on two cues:
1) the time domain cue that is the floor reflection which is effectively absent in the case under consideration
2) the frequency domain cue that is HRTF which is neutralized in the case under consideration because there is roughly equal amount of HRTF-related high refequnecy content coming BOTH from below - in the direct sound and from above - in the first ceiling reflection so both HRTF vertical cues effectively neutralize each other!
1. Actually there is usually some diffraction present. I think Carlsson got around this (in the treble region) by using a lot of felt on the baffle that basically absorbed the otherwise diffraction at the edges (for what was a small box sitting on the floor).
2. Depends on the Loudspeaker design. IF the pressure at listener axis is severely depressed relative to the multiplicity of ceiling reflections at higher freq.s - THEN (and only then) will the ceiling start to really influence an image's perspective. Otherwise it's only about the directivity of direct sound at higher freq.s.. (..and you can test this with absorption on the ceiling.)
For the most part - tilt a typical loudspeaker backwards, 45 degrees (or more) and image height will move upward somewhat. This is because the loudspeaker's on-axis response is higher in level than the listener's axis.
You can also improve image-placement "width" in the same manner (..an increase in pressure left of left and right of right relative to the listener axis).
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And yet I have done it over and over.
consider please how extensive and complex wall and ceiling acoustical treatments have to be to be really effective:
RPG Diffusor Systems, Inc.
Can You do anything like that with the floor?
Please don't tell me that a thick carpet does it all. Be serious
Who said thick carpet does it all? I said a thick PAD, high PILE carpet, and digital auto EQ. Is reading comprehension an issue with you as well?
You keep offering p!ss poor examples of your point over and over again. Do you see the size of those rooms? They are way larger than our home listening rooms, and have far different acoustical problems than small rooms. Not one of those pictures is of a regular size listening room with speakers, but all are from unampified performance spaces. A performance space's goals are very different from our reproduction spaces at home. These rooms have RT issues that we don't have in our home listening rooms It is also well known that RPG products are design for large spaces, and not so much for smaller ones. Another fail.
Having a thick pad, high pile carpeting, and digital auto EQ was all I needed to reduce floor bounce to an inaudible occurrence. Lastly, how I treat my ceiling versus my floor is very different. You cannot compare a ceiling treatment to a floor one and still be taken seriously.
Who said this? However it does not really matter in the grand scheme of things. No acoustician that I know of has ever stated that the degree of coherence when it comes floor and ceiling reflection was important or even relevant. They do agree that laterally it is important. They widely agreed that no matter what(and even in a anechoic chamber by the way) that floor and ceiling reflections are bad PERIOD! That never stated that the degree of delay made any difference, and if it was an important caveat - I am sure they would have said it. You are only person in 25 years in audio that has stretched a rubber band this far, only to watch it pop right back in your face. It is a bogus point(and red herring I might add) when it comes to vertical reflections.
By design a flooder produces more reflections than direct output - hence why it is called a flooder. It floods the room with reflective sound. Unless all of the reflections have the same frequency response and tonal characteristics as the direct output, it will color the sound. The timing of arrival of the reflection does not make much of a difference if the frequency response of the reflection is different from the direct output - much like you would experience with a flooder. Tube trap.com states this.
If there are many reflections, randomly offset in time, the phase add effect averages out to zero and the composite(or cumulative) sounds just like the direct signal. Whenever reflections do not sound like the direct signal, the composite also does not sound like the direct signal..
Can you prove that all of the reflections from a flooder sound like the original direct sound when it hits the ears? I bet you can't, and that is why your explanations lack credibility. There are some here that can wade through you mud and get clear water.
Once the sound from a flooder hits the front wall(before it hits our ears), its timbre changes even if it is within the 30-50 millisec fusion period. Once it hits the front wall and then followed by the ceiling and floor reflection(before it hits our ears), then its timbre and frequency response has really been altered and that leads to comb filtering, smearing and tonal changes. These are facts.
I cannot believe you are trying to sell me snake oil responses and theories that have not been proven or even slightly tested scientifically. No where in Toole's book does it say that reflections from the ceiling are complimentary to getting good sound. It does say that ceiling reflections are a problem that must be addressed. I have already named the acoustic professionals that agree with this, and disagree with you.
Have You? Then please tell us more. Make a valuable contribution to this thread
please
I wish I could, but I hated the bloated diffusive imaging from the three flooders I heard. Using my recordings and listening room as a reference(since I know exactly what they sound like), they sounded nothing like what I heard in my studio(or later in my listening room) while mixing and mastering them. The diffusive nature of this type of speaker(which I am sure is why a few people like them) made a violin solo in the left channel sound like it was coming from the left and center of the sound stage. The orchestra instruments that had very defined places in the sound field were "sort of" there and ill defined. Transients and attacks were softened and blurred and had no snap. The speakers lacked deep bass, and sounded bloated in the upper bass. Images were also unnaturally "stretched" vertically when compared to hearing them on my Dunlavy's, ATC SM 300 and Thiel 3.7's The whole presentation sounded more like an "effect" than it did like what I heard when recording, mixing, and mastering them. In saying that, there was very good depth at the expense of detail. Only fair lateral imaging when compared to the Dunlavy's and Thiels, and some tonal changes of some reed and upper brass instruments. There was also a lost sense of air and upper frequency openness when compared to my listening room and studio speakers.
You asked me to use my ears, and there you have it. The presentation I heard from flooder's was inaccurate and unrepresentative of what I heard from the 2 way front firing speakers in my listening room, and the speakers in my post production studio.
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Well, I don't live in Denmark, and neither do billions of other people on this planet. So the relevance and importance of this statement is nil. Here in the states, wall to wall carpeting rules, and depending on the age of your house so do diffusive "popcorn" ceilings.
No that is not what I said. So its true, you cannot read. I said a front firing design is more common and well understood design than the flooder. I stated clearly that there is a reason that flooder's are unknown. They are no better a design than front firing speakers, and offer no advantages as well. I also stated that I know of no mixing or mastering studio that uses flooder's, and playing back a recording that was mixed and mastered with front firing speakers will not translate very accurately to flooder's. I know this because I have heard my own recordings on flooder's, and they sound nothing like what I heard in my studio which uses front firing speakers.
Great, for it. I think it is great you like "effect" speakers like Graaf does. Different strokes for different folks I say.
the topic has been thoroughly discussed in this thread - the soundstage is NOT abnormally low, the sound is NOT coming from the floor
why? here is why:
it is because vertical localisation relies on two cues:
1) the time domain cue that is the floor reflection which is effectively absent in the case under consideration
2) the frequency domain cue that is HRTF which is neutralized in the case under consideration because there is roughly equal amount of HRTF-related high refequnecy content coming BOTH from below - in the direct sound and from above - in the first ceiling reflection so both HRTF vertical cues effectively neutralize each other
You may not be getting a floor bounce, but you are getting a floor and front wall boost and that changes the frequency response of the recorded signals. So already the floor boost (or boundary reinforcement) has already altered the reproduction system versus what is on the recording.
Can you show me proof that a flooder's direct output, and that from the reflection from the ceiling is exactly the same in terms of high frequency information? I cannot see how it would be because before you hit the ceiling you are hitting the front wall first. The ceiling would be a secondary reflection not the primary one. Reflections alter the timbre and tonal qualities of the recording, so I cannot see how a floor boost, and reflections coherent or incoherent would have the same frequency response and tonal characteristics.
The ceiling in my reference HT room is 20ft high. Can you really make the point that the direct output and the reflected ceiling high frequency output would be the same at the listening seat when the distance from the speaker and listening position is different than the distance between the ceiling and listening seat?
I want to see proof that your theories are correct, you word is insufficient. I would like to see a measurement from 1 meter, and another one from the listening seat to confirm the high frequency information is identical. A theory is one things, and field measurement to confirm it is another.
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perhaps, because I had a strong impression that it was predominantly:
etc.
still the acoustical coefficients ( http://www.rpginc.com/docs\Technology\Presentations\Acoustical Coefficients.pdf ) stay the same, which means that a given acoustical treatment is equally effective in controlling a given reflection no matter how big a room is, RT has nothing to do with it
the floor bounce in the frequency response probably, yes, but not the time domain localisation cue of the floor reflection
Surely I can compare two reflective surfaces, why not?
perhaps because with conventional speakers they cannot do anything to make them coherent enough to hear any difference?
Tube trap.com states that "the frequency response of the reflection is different from the direct output" in case of a "a flooder"??
well, It cannot be at all proven how anything "sounds like" because it is subjective
But as far as measurements are concerned it is sufficient to prove that early reflections are essentially similar copies of the direct sound.
Let me ask You to take a look at the scheme that I have posted and to take the law of reflection into account, ok?
You can always tell us what exactly were those "flooders"?
Are You sure that the sound was not coming from the floor?
any gain from the adjacent boundaries can be easily corrected in the frequency domain, even by means of a passive circuit, not to mention digital autoEQ
how high?
Take a longer look at the scheme please. There are both a first order ceiling reflection and a second order ceiling reflection (via the front wall first order reflection).
according to Toole only incoherent reflections alter "the timbre and tonal qualities"
You know Toole's opinion on the so called "comb filtering", do You?
why at 1 meter? what for? Also "identical" is unnecessary. Coherent is enough.
I can show You polar response graphs of a typical recommended driver:
Attachments
the floor baffle can be removable, both of them actually, no practical problem
Anyway, I don't employ any for the time being.
I believe that they are really necessary for a serious critical listening only and I don't have much time for a serious critical listening these days
only headphonesThose baffles are a solution for audiophile perfectionists. For simple enjoyment of music they are unnecessary IMHO.
Such baffles can be improvised with anything flat and hard, I also tried the Carlsson approach and I used cushions of various sizes. I think removable baffles are better solution than absorbing panels even if only for practical and decor reasons.
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Well, I don't live in Denmark, and neither do billions of other people on this planet. So the relevance and importance of this statement is nil. Here in the states, wall to wall carpeting rules, and depending on the age of your house so do diffusive "popcorn" ceilings.
Why can you use such statements and not me? It's not fair
No that is not what I said. So its true, you cannot read. I said a front firing design is more common and well understood design than the flooder. I stated clearly that there is a reason that flooder's are unknown. They are no better a design than front firing speakers, and offer no advantages as well. I also stated that I know of no mixing or mastering studio that uses flooder's, and playing back a recording that was mixed and mastered with front firing speakers will not translate very accurately to flooder's - If you state that front firing is more accuratet to the mix, then it must be better. Otherwise I don't know what you are saying.
I know this because I have heard my own recordings on flooder's, and they sound nothing like what I heard in my studio which uses front firing speakers.
Great, for it. I think it is great you like "effect" speakers like Graaf does. Different strokes for different folks I say.
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Did someone mention that the sound from such a near-floor speaker is coming from the floor?
I've experimented with many different radiation patterns, tilt, toe-in and equalizations. Sounds are always coming from locations below ear level. It somewhat depends on the sounds themselves.
The interesting aspect is that the auditory scene from a near-floor speaker can be spatially less ambiguous than a normal stereo setup (this is not generally true). Obviously one or more detrimental cues are removed. I'm not sure it's the floor reflection. It simply might be the increased reflection free time.
I've experimented with many different radiation patterns, tilt, toe-in and equalizations. Sounds are always coming from locations below ear level. It somewhat depends on the sounds themselves.
The interesting aspect is that the auditory scene from a near-floor speaker can be spatially less ambiguous than a normal stereo setup (this is not generally true). Obviously one or more detrimental cues are removed. I'm not sure it's the floor reflection. It simply might be the increased reflection free time.
Did someone mention that the sound from such a near-floor speaker is coming from the floor?
well... on the contrary actually:
Joachim Gerhard refers to his own and others experience with the Snell Type 1:
http://www.diyaudio.com/forums/full-range/162827-mpl-33.html#post3478143
None of those people is commenting about sound coming from the floor. It is not mandatory that we hear sound coming from the direction of its source in each and every case.
tell us more Markus, what exactly have You tried?
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or simply all those factors You mentioned, all of them, at least this is what follows from theoretical analysis of a FCUFS
I really wonder what You did wrong that You had this sound coming from the floor phenomenon in Your experiments.
This is really puzzling.
Virtually nobody besides You reported anything like this, this including highly uhm ...sceptical
Mr Soundtrackmixer.
Graaf,or simply all those factors You mentioned, all of them, at least this is what follows from theoretical analysis of a FCUFS
I really wonder what You did wrong that You had this sound coming from the floor phenomenon in Your experiments.
This is really puzzling.
Virtually nobody besides You reported anything like this, this including highly uhm ...sceptical
Now I feel so left out
.I just mentioned yesterday that the direct sound from an FCUFS comes from the floor/wall juncture.
I had placed the only handy wide dispersion "full range" speaker (a Grundig Yacht Boy radio, 60mm speaker, 35mm cabinet depth) at the floor /wall juncture, closed my eyes, spun around, and from any position in the room the sound was easily determined to be at the floor/wall juncture.
This fact is easily explained by the Haas precedence effect (we localize sound sources in the direction of the first arriving sound) and the ear's pinna which account for vertical localization.
My hearing ain't what it used to be, but it certainly sounded like the FCUFS speaker was located where it was.
Not surprising, when I hear a cricket chirping I look down to it's position, when I hear a bird singing in the aviary, I look up to it's position.
Some people's pinna may not allow the vertical location precision I enjoy, I find it nearly as easy to pinpoint vertical cues as horizontal.
If it makes you feel better, the Yacht Boy is normally sitting in the kitchen window sill, pointing at the ceiling.
At that position, it sounds like it is in front of me (which it is) when sitting at the kitchen table.
As I mentioned yesterday, I prefer the sound field for music to come from in front, rather than from below.
Note that the small size of the speaker (acoustic center only 65mm from the wall) and it's thin depth virtually eliminate the floor and wall delayed reflections, similar to the baffles you proposed (but don't use) in post # 2341.
After realizing that today, I placed the Yacht Boy on a box of tissues and moved it away from the wall a bit, approximating your KEF speaker's acoustical center location.
The location cue I heard was still at the floor/wall juncture, but had become more ambiguous, "smeared".
Probably for those "audiophile perfectionists" that prefer the additional jumble of reflections the FCUFS provides, the baffles you suggested in post 2341 would not be a good idea, unless a downward listening angle is preferred, similar to listening from a balcony in a theater.
For what it's worth, I prefer front center to balcony seating, unless it's a dance concert
.Art