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