0:00:13okay so the i mean that's is that the um the a is about
0:00:18spatial sound reproduction but you see i would lost because
0:00:22so
0:00:24um so that's
0:00:25let me
0:00:26just discrete we go to the um somewhat deviation or some background
0:00:30this you know i mean we could do these bases all reproduction and
0:00:35with in you and side um
0:00:37in a given region of space
0:00:39so the idea is to you were besides sound feel
0:00:42but spatial sound you produce it using a
0:00:45a bunch of laws speak
0:00:47so there are two common techniques meets people use
0:00:50um in the a great is if you want to use the if you synthesis so
0:00:54using using good job of most in table
0:00:56okay cage to uh and in the one is sound
0:00:59you know
0:01:00called seed in the or spherical harmonic decomposition all
0:01:04oh commonly high is one
0:01:06um
0:01:07so
0:01:09one thing
0:01:10we the what of these techniques are uh um
0:01:14with a pure tried to use them
0:01:16to reproduce a sound in a you each and
0:01:19you need actually be a a lot of a large number of
0:01:21also
0:01:23works on but um
0:01:24you you
0:01:26for a frequency say a um a or we have number K with though
0:01:30we have let them down
0:01:32um
0:01:33if the reproduction region is a radius of a a a a a in a number loudspeakers you need is
0:01:39approximately
0:01:40so to um
0:01:42to times they are bus once a proportion to the frequency
0:01:46um
0:01:47is
0:01:47what was it may not bad in the use of the agent so
0:01:51mean you
0:01:52what to have a you
0:01:54not i mean and if you want to increase D frequencies then
0:01:57or be see the number of all goes are going to be a um
0:02:03in a sense on really
0:02:04so for example a um a production or what a point one meter radius at sixteen khz takes quite like
0:02:10sixteen all speak
0:02:12so that's in a a a a a few assume a to be
0:02:15a three
0:02:16but if
0:02:17it's the three D case this and number of speakers are going to be the while K are one
0:02:23approximate
0:02:24so that a seven one O the
0:02:26uh a go back so he
0:02:28i i some um
0:02:30that's
0:02:32a another another issue use um
0:02:34i you try to do this production or when an yeah yeah
0:02:37or B S C
0:02:40you do you know room there would be a real a coming from "'cause" his own was
0:02:44you know outside region as well
0:02:46so there a unit selection it back so that we
0:02:50um
0:02:51change you or or you know so on so
0:02:53to compensate that
0:02:56sometimes you can be black station type need so
0:02:59okay be in these algorithms
0:03:02to the um
0:03:05um
0:03:05compose
0:03:09and and also the it has been shown that if you use
0:03:12rather than just the only directional all speakers by
0:03:16um
0:03:17first the save a type or
0:03:19or fixed directivity loss because you can actually
0:03:24right we use used is on feel going outside the your regional well
0:03:28you you uh decide which region
0:03:30so the mean we all the X
0:03:32in do you have a less if you in the
0:03:35region channel of interest and then to be outside you'd all speaker arrays
0:03:39exterior F feel
0:03:40so
0:03:41you things say takes into the of if it's indices
0:03:44using a a
0:03:46type was you can actually eliminate the outside side uh three
0:03:50well of course uh are you is a problem that
0:03:55the
0:03:55the coming from
0:03:57um was and things like a
0:04:00um
0:04:01a another a a local background um so
0:04:04there is a thing about this frequency bin you do in the boat also we got a sweet he's um
0:04:10which just a simple D
0:04:12if we can corresponding to the um i'll wavelet separation in a lot of speakers you looking at say
0:04:18um
0:04:19my my of that
0:04:22um um so as i say in U K to have a some works which shows that if you use
0:04:26the fixed that to this because you can actually use these
0:04:29some be going outside
0:04:31just codecs C
0:04:32P
0:04:34okay so i
0:04:35so that is a summary of the shows these spatial sound you button use one is the you need a
0:04:40large number of those speakers and do is these
0:04:42reverberation operation and from if you give you
0:04:46so you we nine see if we could use the less number of all speakers
0:04:50and also
0:04:51um
0:04:52you can have
0:04:53you going outside to sixty if you
0:04:56less me my
0:04:58so what i Q can be of this paper is that
0:05:01we use a i would've be able to to be with the loudspeakers speakers was sound reproduction in this particular
0:05:08there but be just using two D case
0:05:10um so that means
0:05:12use to you have used
0:05:14all speakers
0:05:15which one
0:05:17be able to produce a variable a really factor
0:05:21and then you combine the or
0:05:24in a area to produce your
0:05:27and then be show that if you use
0:05:29and in for the variable
0:05:31um
0:05:32also does
0:05:33it actually you can increase that night it's we can still the maximum operating frequency by in time
0:05:39well the on the
0:05:41well
0:05:42i if you keep the frequency constant can increase the regional reproduction but it does it's all alternate view you
0:05:49can
0:05:50the D V A the uh each of size and in the um
0:05:54if we can see then you can use the number of rows because by a one in time
0:06:00okay so
0:06:01oh what is fairly small the about these
0:06:04how to design
0:06:06these are what the lost
0:06:08so this is about you know
0:06:10for some way P can have a was five the because of you can use them to um a is
0:06:15it sounds
0:06:17okay so
0:06:20normally a it decides on a you put really i mean would be written using
0:06:25this see question this is just a
0:06:28does this is an interior feel so we in the last week at right
0:06:32so this is given by a
0:06:34a gain for the two dimensional S which means um you just assume you i mean
0:06:40so that's is given by a
0:06:41that's a function of which you know be a you know
0:06:44and frequency frequency and the yeah
0:06:46and then
0:06:48the
0:06:48i decides on a you you can be given by a bunch of corporations
0:06:52C
0:06:54so because of the do to some of the as a function for this you can get these
0:06:59spanish and do in
0:07:01um say in the as minus in the class
0:07:05so
0:07:06if we use see um a only directional also speak at it in both C
0:07:12it'll it'll all speakers V L need to be able to say when class
0:07:19so i
0:07:20so it's a close we all but was that sound really is given by that
0:07:24and then the idea ugly i good how do you are this this you using a us position at a
0:07:29and for example of this paper or you see that just a circular
0:07:34okay so
0:07:35if
0:07:36just use uh when many directional a speakers does then
0:07:40you put to D case
0:07:41the um
0:07:44each house case of more what which is you one by a proportional to this
0:07:49five the at least the H not use this zero or and and of function
0:07:53and then these are
0:07:55are is a a a way to to what any point in B
0:08:00we a um is and then are in the of a point where
0:08:05oh with that the uh
0:08:07but to were a one of the last
0:08:09so you can expand that a function
0:08:13you seeing his the known i is so
0:08:16for or do you favour yeah the are is that they use of the also that it you have this
0:08:21expansion
0:08:22and a full
0:08:24exterior for you you get is too small and then you have that
0:08:29so yeah in in a is the M board in did not handle a function and the G in he's
0:08:33the import a a a a a as a function
0:08:36so it
0:08:37if you use it go to
0:08:39sound source sort all speakers
0:08:41then
0:08:43the
0:08:44you can expect you would have a
0:08:47um
0:08:48a song you given by in these fact that we use in the the um
0:08:53that it would be better
0:08:55we the a a
0:08:57detection and debate
0:09:00so
0:09:02yeah
0:09:03B that really is a um and the B
0:09:07this uh
0:09:11and the to the vector from whatever the set
0:09:14so you can you can expand this this the
0:09:17you two cases the exterior case and they a so you use and the next year
0:09:22so um again you don't use a a a as a function come here
0:09:29so do
0:09:30you can see that there is a and and and and is in plastic that yeah
0:09:36otherwise the laws
0:09:37the the difference between X T D and the D V is that
0:09:40uh a the change of changing
0:09:44okay so
0:09:46a a dollar to sound so is this i mean if you combine
0:09:50say a a the and mine mine have lead to be that you can pretty much yeah it a five
0:09:55and signed by data
0:09:57be that but
0:09:59so it a lot of each use it general and the order to do the variable T
0:10:06we uh
0:10:07yeah can be additional these still we can say a and and of the other that in order of this
0:10:13will produce a fear
0:10:15given by then
0:10:17you know who the these of the month of what we still for each
0:10:20in the war
0:10:22uh
0:10:23a uh that so be
0:10:26this C B
0:10:28uh
0:10:29yeah i'll speak and in U the
0:10:32what's the waiting for the in the word
0:10:35so
0:10:37you can do it and huh
0:10:39what we could do is you can you quit that should do
0:10:43you you desired sound field so this is you'll some field due to the you use a means in the
0:10:49all all speakers and then
0:10:51you can do a great that do you would decide on we
0:10:54you know to good both sides by a um
0:10:57E J say in five and then um
0:11:01and get a more demanding solutions so called more a solution for
0:11:06will be to get a feel that exterior
0:11:09so you
0:11:10do you have a we have a a bunch of corporations speech use your decide
0:11:15of which i
0:11:16um this as your decide sound and then what we stay at a model
0:11:20a sixty via field um you are required a you would like
0:11:24that is no in it to goes outside so you can and
0:11:27assume be coefficients were you zero
0:11:31so you call these two haitians for you get more than X T V more full in goes from minus
0:11:37in
0:11:38so now you can actually to combine these two iterations to get the
0:11:42for a single
0:11:44system C
0:11:45see
0:11:46so the
0:11:47um at icsi creation
0:11:50so
0:11:51you can combine density H
0:11:54does include a um
0:11:57you know what these five does to get as so
0:11:59yeah i a it is then to try to find you E
0:12:03main peaks
0:12:04we make good she's for each again in each model me
0:12:09each also
0:12:10so
0:12:11a you can so that a and then um
0:12:13you can use it to uh
0:12:17yeah can
0:12:19so
0:12:21a was to to do that you need to have a
0:12:24you know a little available more you to be less that the
0:12:29it put at all
0:12:31yeah um
0:12:33C the in nice the high as a little but speaker and it is the number of lost
0:12:39um and also we know for a given region
0:12:42to have that
0:12:44uh you a number of we produce a little more of are given by frequency time i
0:12:51so uh we do matter that's a relation of the so we choose a circular area and at fifty i
0:12:57of that all speakers
0:12:59and add it is easy and he does
0:13:02so for this particular case if you just use a zero order that the corresponding i
0:13:07frequencies
0:13:08hundred
0:13:09so
0:13:10so this is i
0:13:12really is a so you have a result is due to a
0:13:17a source located at radius of six meters and and uh that is sixty three keys in fact ah ha
0:13:24two loudspeakers
0:13:27so
0:13:29this is the uh
0:13:31he produces on the other
0:13:34will be used
0:13:35the first-order loss does
0:13:37and
0:13:37frequency hundred hundred by uh
0:13:39so as you can see so the the the or see some yeah there are six meters does that they
0:13:44so you can see a feel inside and then
0:13:48um the on side exterior field is um
0:13:51lace
0:13:55and then in this
0:13:56case yeah D
0:13:58the same system
0:14:00so we got you know it's because the the but the data and
0:14:04three hundred fifty the so was you know this is a ball the night this frequency so that
0:14:09um corresponding E
0:14:13the
0:14:13the set little
0:14:16you know who a a a guess is yeah okay K be pretty C
0:14:20some has has been really use
0:14:22from the origin of that
0:14:27and
0:14:28and really got it yeah that's S here is defined by a suppress a
0:14:33difference be in the but is field and that the original you divided by the patient the origin
0:14:40um that
0:14:41for do you feel that well
0:14:43X T because all the of you use you zero so is just
0:14:48uh
0:14:51section
0:14:53so i this is the average production um there uh
0:14:57first order of speech data
0:15:00and we we hundred three fifty and it
0:15:05so as you can see um
0:15:08there is you can do uh side and
0:15:11yes the the inside that region
0:15:14uh you have a
0:15:18and
0:15:20okay and then you look at
0:15:22you see
0:15:23the door the
0:15:26also so on and still we can be not of lost just to fifty
0:15:29and then we increase
0:15:31the uh
0:15:32you you a region also but the three
0:15:35and the at that to you have so in this case of B S you can see
0:15:42original
0:15:42reproduction production has increased
0:15:45again
0:15:46and then all side but it's see a few of them
0:15:49be the listening to
0:15:53and this is the you but i it or is this case of as you can see "'em" was you
0:15:57mean you will was it well as the
0:15:59shah
0:16:01the door to
0:16:02mean
0:16:02got a lot of is but inside and outside this list of this
0:16:07and this C is a case we a seek store the
0:16:11also because again in know speakers and eight hundred uh so this case
0:16:16um no no is the other side
0:16:17use small zero
0:16:23so yes yes a could close and um use these file it allows is just to see
0:16:29you know what C whom and you can have a so what we have concluded that
0:16:33but using in order
0:16:35as you can
0:16:36L of them by in time
0:16:38you know i the frequency or radius of convergence all
0:16:42in this is that you can do not loss because by one or
0:16:48Q
0:16:51i
0:16:52i
0:16:53i
0:16:56oh
0:17:05uh_huh
0:17:06so
0:17:08um
0:17:09i think you can only code
0:17:13yeah i mean for example it that the what allows a cat who am and that order out could be
0:17:20say you produced by
0:17:21so see um
0:17:23number of circular
0:17:25all speakers it's so
0:17:26but it yeah
0:17:28yeah i i and that's that's it i haven't got
0:17:31well i mean of was that would be you know you tried to
0:17:34are you mean have a
0:17:36uh uh we go to that all speaker a problem
0:17:40um
0:17:42omnidirectional all speakers
0:17:44B
0:17:45yeah but but sites going to be increased well
0:17:48yes so at the end of the day are they going to get get we because so
0:17:52of course
0:17:53some
0:17:55a of this kind of things the the would look at at the
0:17:58um can of properties and things like that are are are that just
0:18:02based on uh
0:18:03action uh
0:18:08yeah
0:18:15i
0:18:22oh
0:18:25oh
0:18:26okay so i mean you know as you know there are not that many
0:18:31higher order to
0:18:32do to get all speakers that such
0:18:34so it is a game
0:18:36people have done yeah
0:18:37right
0:18:38so i mean if you just
0:18:40say kind of of what man vision of a higher order last he's using a
0:18:44um one a whole all speakers to get a
0:18:46so you that we at least to save number i
0:18:49well i was then
0:18:50it is more um
0:18:54so so other that have been um more else because are around the circle to use could be a
0:18:59a same number of rows because the around you
0:19:02point
0:19:02or around the set
0:19:03uh
0:19:06but i can i mean as i say you know that's kind of know how well the version of a
0:19:10high would allows speaker right
0:19:12well you know it's a technology that the video low
0:19:15we you know you using we gone a couple days and stuff like that
0:19:22i
0:19:22more
0:19:26i
0:19:26or
0:19:28one
0:19:29oh
0:19:34i
0:19:36and
0:19:37uh_huh or
0:19:38why
0:19:39yeah
0:19:44or
0:19:47so
0:19:50oh
0:19:52am
0:19:53and it
0:19:56no no i have a look at you mean a lower power consumption known no one
0:20:01that way
0:20:04i
0:20:07yeah
0:20:10i
0:20:10well
0:20:13you
0:20:14a
0:20:14oh
0:20:19okay
0:20:20just six
0:20:22i
0:20:22i
0:20:23i
0:20:26man
0:20:27i
0:20:30why
0:20:34all i
0:20:36i
0:20:37hmmm
0:20:41yeah
0:20:45okay
0:20:45okay
0:20:48i
0:20:48i