2:50, 3:50 Some loudspeakers are designed with the first floor reflection in mind, i.e. taken into consideration in tailoring the loudspeaker sound. I guess they do that because, at least for floor-standers and stand-mounts, the distance of the drivers from the floor is specific or specified and easy to take into account into the design. it's worth remembering that but in any case measurement and hearing will be the final judges.
The floor to listener and the ceiling to listener are the first two reflections to arrive at the listening position no matter how the speakers are4 designed or what the speaker manuufacture says. The reason both reflections are first to arrive is the distance from energy source to boundary surface.
@@AcousticFields Yes. Some British manufacturers were/are taking this into account when calculating the time alignment of their drivers and therefore, make their crossover calculations, driver choices etc. I'm not sure whether every loudspeaker manufacturer does this. In any case it is only done for the floor reflections as the floor-driver distance is a given for every driver whereas it cannot be known for any other room surface. This is why if, say, you place such loudspeakers not according to manufacturer's recommendations with respect to floor placement (e.g. use a stand with a different height from that recommended for a stand-mount) you should experience a sound that is different from what the specifications describe. Given the average room size in Britain, one should expect this first floor reflection distance to be quite small, e.g. 1.5-2.0m in some cases. This means a distance around 2.8-3.1 m travelled by first floor reflection wave assuming 1.2m ear height or around 100Hz and harmonics. For a typical lounge this distance maybe slightly higher but not by much. Of course this quickly gets more complicated when you have more than two drivers so I don't know what the voodoo applied is but perhaps anyone sufficiently interested can find out by sampling hearsay from the audio industry grapevine.
How important is floor and ceiling treatment for planars? I have a 2' x 4' diffuser behind each of my two planars, should I add more diffusers in between them? Thanks for your reply about diffusion on another video.
I didn't get how or what the "16 2/3" rule is...You kind of mention it at the beginning and end of the video, but never integrate its meaning into the video. Otherwise, wonderful as always!
Hi RB, Each surface of your room contributes to what you eventually hear in your small room. The low frequency issues in your room are pressure related and are impacted by size and volume. The reflections, Rt-60 times, are surface related.
Ah, but the percentages are not truly the same. Elsewhere do you offer typical proportions? I'm guessing more like sides and ceiling 20-25% each, then back wall 15%, front wall and floor less than 20% together.
I came here to learn why the frequency of the train AC power in Switzerland, Germany and Austria is 16⅔Hz. Guess that's the wrong video to learn this 😅
Hi RB, Vibration through structures is an issue that can be addressed using damping or isolation technologies. Which one to use depend on frequency and amplitude of noise.
I think Dennis is focusing on the reflections from all six surfaces to your ear, not the size of each surface. All six contribute to the sound, each at 16-2/3% X 6 = 100%.
2:50, 3:50 Some loudspeakers are designed with the first floor reflection in mind, i.e. taken into consideration in tailoring the loudspeaker sound. I guess they do that because, at least for floor-standers and stand-mounts, the distance of the drivers from the floor is specific or specified and easy to take into account into the design. it's worth remembering that but in any case measurement and hearing will be the final judges.
The floor to listener and the ceiling to listener are the first two reflections to arrive at the listening position no matter how the speakers are4 designed or what the speaker manuufacture says. The reason both reflections are first to arrive is the distance from energy source to boundary surface.
@@AcousticFields Yes. Some British manufacturers were/are taking this into account when calculating the time alignment of their drivers and therefore, make their crossover calculations, driver choices etc. I'm not sure whether every loudspeaker manufacturer does this. In any case it is only done for the floor reflections as the floor-driver distance is a given for every driver whereas it cannot be known for any other room surface. This is why if, say, you place such loudspeakers not according to manufacturer's recommendations with respect to floor placement (e.g. use a stand with a different height from that recommended for a stand-mount) you should experience a sound that is different from what the specifications describe.
Given the average room size in Britain, one should expect this first floor reflection distance to be quite small, e.g. 1.5-2.0m in some cases. This means a distance around 2.8-3.1 m travelled by first floor reflection wave assuming 1.2m ear height or around 100Hz and harmonics. For a typical lounge this distance maybe slightly higher but not by much.
Of course this quickly gets more complicated when you have more than two drivers so I don't know what the voodoo applied is but perhaps anyone sufficiently interested can find out by sampling hearsay from the audio industry grapevine.
The "Thank-you" at the end of every video is the part I find myself quoting everytime. haha Love it.
How important is floor and ceiling treatment for planars? I have a 2' x 4' diffuser behind each of my two planars, should I add more diffusers in between them? Thanks for your reply about diffusion on another video.
I didn't get how or what the "16 2/3" rule is...You kind of mention it at the beginning and end of the video, but never integrate its meaning into the video. Otherwise, wonderful as always!
Hi J, If you take the six surfaces of a room, floor, ceiling, and 4 walls, each surface contributes 16 2/3% or 1/6 of the total sonic picture.
I was wondering that myself. Thanks for clearing that up. I assumed you also have something about 16 2/3 rule in another video.
Hi RB, Each surface of your room contributes to what you eventually hear in your small room. The low frequency issues in your room are pressure related and are impacted by size and volume. The reflections, Rt-60 times, are surface related.
Ahhhh- now i get it!
Ah, but the percentages are not truly the same. Elsewhere do you offer typical proportions? I'm guessing more like sides and ceiling 20-25% each, then back wall 15%, front wall and floor less than 20% together.
What can i put on the floor because on the ceilings I can always put hanging absorptions. What on the floor though?
What is the issue you are having with the floor. Is it a pressure or a reflection issue?
@@AcousticFields To be honest I don't know . But reflection is my concern
I came here to learn why the frequency of the train AC power in Switzerland, Germany and Austria is 16⅔Hz. Guess that's the wrong video to learn this 😅
another great video. The suspended slab is interesting. I heard Electric Lady initially had some issues with vibration from the NYC subway.
Hi RB, Vibration through structures is an issue that can be addressed using damping or isolation technologies. Which one to use depend on frequency and amplitude of noise.
100%/6=16.66?
That can only be true if the room is a perfect cube!
C, We are illustrating the concept of cause and effect. Stay focued on the concept to further your comprehension and understanding of the issues.
@@AcousticFields
Ok, I'll bear with you.
Thanks 😊
I think Dennis is focusing on the reflections from all six surfaces to your ear, not the size of each surface. All six contribute to the sound, each at 16-2/3% X 6 = 100%.