Gadgetory

give this a go my name is Tyler sins on the editor Jeep of infidelity I measured and probably have about a thousand edible veterans like my time we've got 500 of on-air fidelity and the course or many measures that don't quite make it for one reason or another Arab Americans of something that I can't publish and also a lot American consecutive loss in room hey so the first thing to know is what we're looking for is flat that there is such a thing as flat it's put a speaker in an echo chamber microphone down directly in front of the speaker the speaker is perfectly flat response the same at all frequencies as the same game will see that out of microphones is we're going to call that flat and we're going to try to figure out what that looks like a pair of headphones now I'm not saying that perfectly flat is best we don't know that exactly we don't know where lash is yet but it's a reference so it may not necessarily the sound the best it certainly doesn't take can we count all sorts of things like and so forth but its start so this is what hippo measurement she looks like that frequency response up there and that's what we will talk about first and just to identify all the things i'm here on your second sheets custom that's frequency response that is a undirected frequency response in a correct frequency responsible second that's isolation how much noise is held away from you and you listen pair head low so sealed hip bones will show Bieber amount of isolation this is the impedance and electric bass response to the head bumps this is the 31st square wave response and then the 300 square way in response the impulse response and a total harmonic distortion 2 plus noise and then we got a couple little things here numbers here that give us a vision see and broadband isolation and a couple of other things but for starters we're going to look at frequency response good ears we say a speaker's flat we just put a microphone out here put it in an antelope chamber or as the gentleman who parties it a two signals and give this microphone measures flattening on that speakers flatten all is good now the problem is what you hear we can put your head in front and what's that you're here in reason why that is important for headphones put headphones on there is no place to put a microphone in there where you have some kind of audio signal that's propagated by it without a bunch of reflections around it last year was known us about gating signals so that you don't get any reflections in the in the measured signal and then you can know what's really there well in something that's this small you're not going to get away from them questions there's all sorts of stuff going on inside this coupler that's important word understands headphone cutler so it doesn't sim sound out into space for propagating it couples the sound here here and the only legitimate place for you to measure sound in a headphone is after hear from because well that's what it's intended to do just get sound to your ears flat so well with a splat look like at the eardrum that's what we're after you what we're going to go after your first is take the microphone way put your head project and what does the frequency response to look like at your eardrum and why so this little chart I just love because then personally like one that I found and that's it this is a for a 45 degree angle of incidence so Sam times and 45 degrees the way to do what the eq love that sound is due to your body your head poor so the reflections off your ears and so on and so forth in each of these lines represent a different opponent of eq that happens and this big line is the overall the song so 4 45 degrees off-axis at the eardrum you're going to have 20 p at about 2.7 k 20 DB p as a lot but that's real and that's what your head is you see here and your head is amazingly good at figuring out how to hear something in make it right your brain wants you to be able to understand what you're hearing and it tries very hard to make that work and you live this curve your whole life and therefore it sounds flat E so where does this come from ok so number one here is the spherical head so your head has gained at high frequencies as you go up in frequency you mentioned up in a oceans any air and water the shoreline saying you know appear from a pilot that goes to a dog or something like that so you get water and appear right there if you have the lone waves they're going to write pass that piling lately underneath and that way is going to say just like it is when you look at the edge of the pie in your head but as the waves get faster and faster and faster pretty soon the wavelength of waves are getting to be a habit lately is about the size of the parley I'll start baggage along and very high frequency little ripples will be a shadow behind the highlight where the ripples aren't because the pilot is completely interfering with the signal so you have boundary game next as the frequency goes up the uncle to to the signal on the side of the head doesn't as it has to reflect and go back the other direction increases the amplitude of the wave next to the side of the head this whole boundary game and down the game is frequency selective with the size of the object that's feeding the sample so as soon as the sound gets me about half a wavelength is the size of your head you start getting some game in the end you've got some game that stays about the same that's one second effect here is the torso and net so this is your body and your neck mixed your head now your body is bigger and so you got more game over here but there comes a frequency where you've got a body and a hedge which ducks of space in between and it acts as like a filter and and so you actually have a point here where it goes negative game and that's where sound is winding its way through between your neck your head a little bit and then uploads or the frequency start advocating so that's another curve because so that's the head and the body of the neck and now we've got these colored curves right here three is the conch up and up and at the flick back Bobo no I'm very conveniently in this illustration they three is the content and that's a major bowl you're here with us this part right here and five this one big one is your prior year from resonance that happens about I think 3.5 of the folks at the etymotic oh there it is same told me as 2.7 eyes will absolutely go okay What's Up boss and then for this is this a little wobbly thing right here this the flange on your pinup making some reflections way you add all this stuff up together and you get this response right here you'll notice you're a 200 Hertz down here so it starts writing actually fairly low and I frankly don't be tired by this group but but there is a rise for a while to be able to one killers and then a much steeper rise of 2.7 and then a curved shape all the hospital 10k and a 10k right here you're about baseline so a 10k it comes down to about the baseline level and if you guys look at well it seemed distant okay so now we're going we're going to talk about prom black that right there was 4 45 degrees and as you change this angle all those curves change and they change all over the place and as your ear changed if people's ears those curves interchange so so we drive every curve that you know really apply to everybody you know listen what happens if it's dirty agree sir all sorts of weird axes when we when we pick well yet in the rural areas and historically to adopted standards for transfer functions or volume free meal in the diffusive put simply pre-filled response is a sound coming directly from in front of you in an antechamber okay that so we have what's the response of the eardrum and the cell phone directly at ease in an Android chamber and the diffuse field response is sort of the complete opposite it's what if Sam was coming at you from all directions in a room that this bad concrete interesting one like that what's the what's the response of the year all right so this is what these responses look like now they're upside down because they're Corrections so flip this over you're going to have something like that curve to be shooting before and the diffuse field curve this one right here it's probably the this you an average sort of responses it's kind of average but it's really not necessarily quite right it wasn't designed for headphones so so the first most important question is that we need to ask is what makes sense for a headphone curve what is the normal acoustic environment that we find ourselves listening to when we're listening to music and sneakers on sneakers all those speakers music is designed and engineered playback monsters so I would contend and have for years that the target of response curve that we should be looking for is what's in the ears when you play good speakers include room that is what headphones are trying to simulate because they're completely artificial think they need to try to do something that's really feel and speakers are so now there's another thing about speakers if you have to understand and that is a good speaker measures flat in an anechoic chamber we can put it in a room it's no longer flat okay because of couple things one is the down regain the room even through the luminous eyes then there's also that power density of high frequencies as the frequency goes up on the speakers the high frequencies tend to be okay so the higher the previous even more themes and less of it is being sent out into the room so the energy that's just being sent out into the room and not for you generally speaking is low frequency heavy so you take a good sounding speaker a plaque measuring an anechoic chamber you put in a room that may sustain to warmer and we're used to that there's a whole lot of research done by Floyd's a little back in the day with Sean olive where they talk about this and they came to the conclusion that you don't want to be turning black one this evening flat and then and take on the warmth of the room included because your ears when you talk in that room when you hear other people talk to that room here here's figure that one out and about this room in description sounds now we play speakers in that room you have to let those speakers paper boom sound like the sounds or your brand's me though this month with moons house so it's important to allow the speakers to energize the moon and to understand that that's your brain perceives that normal so Sean olive or the past a little while has been working on this curve in HR olive is at arbonne international to do a bunch research and will bore you with the details of this research but they didn't take a lot of research I think that we do a lot more research who goes into this like you've made this argument that using subjective testing all sorts of things that dis the party sponsor for pair of headphones and i would say that he's probably really close so this curve right here is that pie that very soft for go start so another about to my nerves here gradually gets about 1k goes up so in this case it's not 20 DB but more or maybe less actually about their King and then it rolls off after the over the top and at 10k right here you are about at baseline and that's what that sheet is on the front of the handout in case time that is that she'd explain putting some numbers at the moment you're just an XY interpret a headphone management you just have to memorize that verb someday I'll be able to put that curb into the computer and get canceled if you use it to correct drink reserved right now I'm i use a different correction curve so the research the correct frequency responses that i have tended want a little bit more tilt and then whole lot of about forty eight or so like that seemed to be correct but I like actually using the raw Americans okay so let's look at the hip bones a good frequency response this is a pair of nad viso hp50 s and you'll see that has this Rising part it doesn't start out at 200 Hertz though it starts out a little higher if you have a rise in part and it goes up about our gdp which without right and it doesn't have it goes up looma too steep here and then mission receivers of the skirt you go up like this we don't even and then it did sound you fast here but it's about at baseline at 10k so here's 10k and is about at baseline and then it rolls off above now that is about as close as you'll get to this curve with care headphones so that is that's good right that's certain anything these amazing cookies this is those curves right up against the regular curve this is the nae right here and this is a pokal spirit professional the 10k there is some people who think that a dick between porque usually it's like 5k dipping between 5 to 8 k may be a good thing Phillips x2 does it and they gave they think that too much energy to take a baby kind of annoying so they talk about how to stay away from it all right so there's that curve you guys have a brilliant I'm going to anywhere explaining of it but it shows you exactly the kind of cross the points at which you need to be aware the Green Line is a speaker that measures flap your room and the way they got this verb was that they put to good speakers in a really good dummy head mannequin head measurement head that looks like that that's my management head like these and they put in front of speakers and they took measurements of it directed space on my little left little right little of little nap kind of averaged out they come out said that perv you saw before and the green one that's flat as a speaker this cost of the absolutely flat and then they've been a bit a lot of work for your elbow people aren't on headphones and they figured it founded people one more base and that base would basically be there if these speakers were not so we go bigger finger it actually has that basement skin or something like that then they also found it people one if there's too much trouble seniors black your group there's really too much trouble if there is some absorption there is an additional weight an old frequency and student this the boundary games in the room so a1 tilt a little bit warm till occurs everywhere in a response in and they found that people want a little bit of they don't want all I frequencies right there and it's right there mister here because it room be a little distance on that get low absorption stuff so it's little Jim Brown years okay so let's do a quick survey of some historically good Johnny impulse is at eight semis are HD 580 famous fans hit them you can see it's got the peak there yeah three and a half that's why I just say so you have papers on most headphones it ends up happening on my 74 stuck with it no bass boom here no additional base so this is a result of Patricia Logan phone as a maid diagram residence of about under purse or so in below resonance the baseball's off of natural result you'll see though that here's the baseline and you go up to 10 k and the 10k not there it's got a little bit of an optional for that but yes campaign so it's this heart back is nominal for 10k a lot of times it's just mine was going off of it at all you'll also notice that there's a lot of great lines there's only two up here and that's because my measure in five different positions so I measure a little bit for looming back a little bit up little bit down to the center and then I average all those memories that's because there's a lot of resonance to go on in the air see there's a lot of it down here you really don't know what's kind of going on and averaging all together with a better idea of what how much energy is that those frequencies told spatial average the DGK similar one kind of summer in the am didn't have that Pete that the 6s your 605 eighty ad comes up a little bit faster test maybe not quite as much bass and if you look above this 3k point it's stayin rather flat so this headphone is that have a brighter through that middle treble region and the k7 one is a brighter headphone 16 people you just saw only though it dropped off nicely crossing the line of 10k roughly otherwise it so it's a very good this would be a little bit brighter in the 650 where the fighting is because I'm gonna go in then the am the beyerdynamic dt a 80 and it's got more like 650 up till this point but it's not quite as high in that point so this is typical might not have the presence that closest to the voice you feel close to the quest but it also at 10 gauge is substantially above the baseline so over here is long so this head was going to have a lot of height red letters and which does so these three pebblez 587 71 and eating your famous for being this triplet pit bulls wears no warm middle and right kind of went somewhere in there there near neutral and that's a 10 year here whatever then we have the eto d5000 which came only after the other people asking headphones and people really white people thought about this is some ability is special about the simple and I wouldn't end what it is is a rising base that people had if you look at this route is long fairly straight warm till that's kind of what you're looking for the compensated version of these grasses long straight club this is wrong but this is close to right right here so I take people like the d5000 because the first night that we get some solid base of this simple along with pretty good response of the poppets got longer leading upstairs and have some nice presents beings in the right place throughout the right time this is a little problematic this should go down to 0 for 2 hurts so you've got some blog here in the lower mid range so this is going to be to make sense out just a little thick lower pit and then of course that will give the 10k if you're so five DB above the line which is going to give this hit bone a little bit of a break brightness to it so all in all this is a bit of a slimy basic phone a little bit of basic situation a little accentuation way up on top but otherwise pretty good between San ivories d800 called by some included the brofest headphone the sam roll along the other traditional open gigantic hit balls have so it's got a little more on the base of the sympathy nice flat response for sure but it really should have started to rise so we're out here to have the presence that we think should be there in person so concerned about how much should be but it's got about the right price at the top but I can is stayin up after three K so it's staying sayang sayang of the six table for starts the ball up so this headphone is got a problem in that sixth gate agent 67 k vision that I said that some people think is looking to have an option is it's not so aggressive more years and that's an accessible problem back it's a lot a lot of front ends that thing you drill holes in your ears if it's not just write it goodbye because of that will see a little later some of the other things and I think I have an 800 response on your she is the second major problem there are patients to take one of the things you do want to look at is the square wave response to the lower square wave response on the right hand side where it has a little overshoot and squarely and that my friends is a very very clean and pull so the thing that you know the 800 doesn't look all that great terms of frequency response butting in terms of its time response is along so that's where it gets its power not from this particular graph on the LCD 3 first time I saw these I went wow I've never seen a handful that is flat like that always an unbelievable so this movers are hearing LCD trees and cleanup and etiquette follow through oh my gosh it votes in heaven base they're amazing and people were just forward by Wow basic sleeping I would contend and we're going to find ourselves as time goes on you're going but it's not enough face you still actually be a little more and I I've got to the point where I think that a lot of these are based light by a little bit the basic qualities heard the extensions curve at of course the matter taste so we don't know stacks is the SR 007 you can see that it's got a nice long sort of rice it's a bit noisy bumpy path we get there big noisy lumpy butt goes up to the right place at the right time and it also sort of comes down nicely until it is here where you've got something going on there's all sorts of stuff went on and in 10 K is have a bit of peak now what you're looking for is the average around 10k at the baseline but there's an eardrum of your account residence at nine and a half pay the second residence near 10 I think it's a it's right around 10k is two points in the first ones to Sydney quite three times this thing somewhere in that area somewhere in that area so there's another ear canal residence it's going to happen there that sort of kind of change around the pen on the sub around it so if there's a 10k that's kind of okay as long as the average around it is down on that baseline and what we see what this is that it probably is there's a little bit too much energy in 10k and forced sex with receptacles and me just a little bright side along that a little too air inside this down here we are looking our battery is due to pad bounce and we'll show you a little bit more that meant that's the headphone bouncing and society your head with the movement of the diaphragm so there's a resonance of the pad so we'll show you one picture that few minutes peplums near the tarpon Kirk we talked about in nad viso hp50 very much like the target term book the sphere of professionals ok so this is where I'm going to take some wild stab at it your severe canal residences you'll see there's a peak their feet their feet there and they're really really clear and my guess is that that headphone manages to excite the ear canal business really well whatever it is it does a good job with exciting to your compass similarly sennheiser by eating both they're over there and one somewhere in there and let see on these headphones is this little dribble rain thing on the front of the printer hurts square wave and you see this surprising often the skullcandy aviators do with there's just a number of headphones to do it and what I found is that it tends not to be a problem so when you see this these three little rings that are going down like that about that period and you see three peaks over here it's probably exciting your business is your brain knows how to deal with that so it depends this tends not to be a problem even though it looks like it might be this is now we're just going through some headphones and look close to the target curve this is the shirt 15-3 really one of the best head on that not you got a nice bass boost in here that kind of them down the baseline you don't have a long run up before which you have to peek in right place and you get a nice falling response afterwards I find this headphone Beatles little bit bright in here and a little bit too bassy down here kind of a smiley faces fit in phone when you see that and focus a little bit too much bass a little bit Swiss trouble it's probably good headphones to listen to it low levels to cut a bit of a pleasure bunch of curved already Phillips x2 this one is a recently designed headphone in Rowan Williams you design this headphone is well aware of all these things that need to talk about so we've got a bass boosted gear of a nice reporting and it stops at 200 hurts this roll off this is an old and dynamic headphone you can't get around it you sealed around this this fall off below the primary driver business so they can forgive in hand got a nice little out here doesn't have the rise so may not have quite that presence that they should have and here's that notch these are the these are the headphones were they very very specifically designed in this notch get rid of any harshness and then you see it comes back a little bit too hot heavy but if you look at kind of an average around this area ok it's low yeah I noticed your energy a 10k but basically you've got yourself down to the baseline pretty much that this headphone sounds a little bit grainy sound it sounds very nice totally but a little bit grainy and I think that graininess you can see and all these little bumps and Wiggles I think what they're dumb as they put this Dana by singers it's squished into the shape that want you and all sorts who seek tricks and it ends up a compensable uneven sound people to access another really handy little headphone instead a nice run out to hear that too much bass since you are deranged unfortunately so it's going to sound somewhat thick this peep is a little bit high so you can get a little extra brightness and it drops off a little too bass ackwards down the 10k in the baseline but there's not this barking pump that's coming down so this is a hip moment it has it has a liveliness to do this p but it also has kind of a loss of snap and air and things like that kind of laughable definition do that kind of stuff now if we're talking about in your response this one of the best in your response headphones I've seen got a little bit of a bass boost it does lead up a little bit high and personally but you know you don't want to have over directly saying either it's got the bump at pre-k as a little extra bump up here this is obviously very common when you see in ear headphones to have you series of both of Peaks that's all that residences of the tubing through all the various of bits a pieces in there got a kind of just mentally averaged about a little bit but generally speaking a good shape for headphone and if you look at compensated response generally speaking is a nice flowing downward that gets steeper over that one each by dre solo tube yessiree Bob can't be Nash and eats too much anymore if you're sola to is actually a pretty good hit phone we got too much lead into the mid range of the base this had one definitely that sounds thick in here but good shape on this and then a roll off back to baseline in 10k but gone missing is the upper trouble so this headphone sounds a little thick and lacks articulation in the upper trouble but otherwise quite close to the target or sponsor this AKG came to 67 on them ts1 and plucks it was the pimple discesa plug settings on and a pretty good response we got our notch there in this region which is probably okay we're trying to keep it the base of going up too much over here and but it's got some bass boost there's other settings that have more bass in with the nice long run up so it's a nice present sounding headphone maybe maybe a lack of high eyes of here musical fidelity and attend this is an example when I listened to it I didn't like it and I measured it I should like this this is good taking your baseless right it's a little excessive comes down fairly quickly you got a nice crease little one run up to your be here the peak here it is 15 PP above which is a little too much and then it stays high and you're getting something for this interview 568 if you get over 10k and well actually we're like still a TV hi and that's what killed the simple this info you listen to it wave right it's just way right and I almost don't see it as he look carefully so it's really important to carefully please grab a th m50x a little bit on the ear so low cost relative low cost headphone certainly got a lot of pad bounce going on down there that's what all that stuff is in here let's just add bouncing around but it's got this you know we're not just its k but that's probably okay we can live with Assad ship its stated otherwise which it does is good too much longer this is a great sounding headphone low-cost headphone all right now some problems okay so here's here's a couple of ims and I see this all too often and it's just absolutely ridiculous but you have a bass boost that goes all the way up to 800 hers I think the base ends way lower than that and it's got 5 10 15 almost 20 bases this is just ridiculous is it it's a mmm portal pebble is probably ok but boy just going to get overwhelmed by the base bowers and Logan c5 same thing is huge amounts of 80 enemy here's a monster turbine on the top and the turbine pro theoretically the German produce a better head home and what do they do between the two well they gave this bass boosted let loose amount they're actually made a little more light hearted urban people liked it work ok fellas followed that trail get it down and then here's the NY here for PT this is where we disembark Miss Annie Killian he doesn't think that the base needs we bumped up but if you look we've got a real nice it is gradually starting a little bit in here maybe you can start a little bit earlier goes up nicely to 13 BB up ready to this area and then falls down we've got a non-jew here which is probably okay and you're right around the baseline intent a and then you've got energy still existing up here so it's good well I would say that the EMA like ER cork p and the ones that are close to that there's a couple models it or is there any more just a tee tee now who has that this it may be the most accurate in ear headphone in terms of trouble resolution and that's been a thought in the head long time and I think I can assure you that need is a ted-like is very very interested in resolution up above 10k and how that how that high frequencies work this is actually a very very good sound hip bone although i'd say like a little bit more basement they got there so here's Pat announced this is a frequency response curve you can see in these curves is a little artifact over here and this is what the wire dynamic bt48 has got air-filled bushes that are pneumatic and a beauty bound salon so that's thousand a lot and I wasn't exactly sure I mean a lot of web work about this I've just learned by guessing you know what seemed to come out of the talking engineers and tell me but I pan well I also noticed on my isolation plot so this is this temple of the edge while I place and I think I didn't understand this for quite a while but you can see that this is 0 DB isolation so I'm getting no isolation of the 100 Hertz and then I'm actually getting louder here at 200 hurts so the headphone is work is not is not only are they not isolating they're actually amplifying the sound that reason is this online isolation plots the same and then I realized that it happens in the same place and this is the bad bouncing against aside your head amplifying the outside signal the outside Sam as it comes in so the outside sound is it is energizing the residents not just the prior here is the driver energizing president here is the outside air outside noise energizing the residence but sure enough those those artifacts are at the same exact frequency home places an effect on from Pat non-psychic head so I told you I also made your headphones in a number of different positions and some headphones are more picky than others about getting the seal and this is a good example of a headphone that has a problem of the seal that you're looking that the future vice is changing over the entire range here as I move these headphones around and this is really common in hip bones that are very very tightly sealed so this stable that has a very very tight seal on the side of your head and what happens is it either seals or it doesn't and move luxury another vision and then and what I will do is a lot of times when I measure my headphone like this I've got some felt that I can sync between the hippo nimah in the in the head so i can make it like a controlled leak like your hair and a lot of times it will make this measuring at home like this less touching the other thing is is if I if I have a really hard time getting hit on to measure properly I will allow Lenny's I could I could have not have this heart of everything here because I can see that it's not sealed right when I'm just an advil but if I've gone through three different positions and it's been a pain in the ass every time and I sit down and it's not sealed right I'm gonna go by I'm letting this one go through because this headphone is hard to steal so I will lay there is an art to do to making these variables there is a degree of control that I have or what he's going to look like and I try to be as honest as I can and then to what the hell sounds like watch I'm devil stop and they're going to take the head blown off and listen more carefully how much is the base how is achieving seal so i can get the feel for what the headphones likes when i put it back on i'm measuring it so that it looks like where I heard so there's kind of a fine art to this thing this is an on-ear headphone and this is a situation where it just seals different no matter where I put it so it's just just all over the place and I just do the best I can for most of the measurements and then in the end see what comes out and that's what you get but you see something like that it's because this headphone just doesn't like to see on the air and then this is the one this is one weird clicks it does one or the other there's this either does this work does that but it doesn't do anything in between and I'll try to get it to do this all the time but a lot of times it was like this is just won't cooperate so I have to let it be what it does but it does have a head on your head as well so it's legitimate to allow these artifacts to show up in the bedroom now um no go to a comb filter it right there humble tourism okay so comb filter is if you take an audio signal and then you keep the same signal and delay it just a little bit okay put it back onto itself get times when these frequencies this end starting it Tina audio signal and you go through a delay of X amount of time and then you genius the Regency as you run up and you get to places where there's Knowles where the half wavelength is that leg and then cancelled out exactly so at five per person 1500 2500 vrbata tada you're going to get cancellations now that could happen in headphone if their sound it comes to the back of the driver around to the front of the driver and enters the area in your here and all for some is famous for this one of the ways that they try to synthesize then there s logic they call it is some of the sound from behind the driver comes back around the front goes into the acoustic chamber and what I found whenever I see artifacts that looked like this is that the headphones are horrible so you can see up here you got this bump and then there's another one right there you can see you can see a post in this and then one more so this is where dynamic t1 but if you look at the square wave responds in time you seem really sharp nasty looking bitches and these if you remember that other set of nice rings are market can differently these are j looking the other rings were nice line which is collapsing down so these have a bar maybe z component because they're not sinusoidal here's another one you can see these very distinct bumps aa-12 and you can see how jagged the responses here similarly the older so mrs. Olfa sometimes mentioning again very very much having usual effects having really disturbing transient responses there so that's one you keep out your eye out or if you see these humpy bumpy things up here and you see this stuff if you're going to have a hit from this tizzy and not very good resolving okay here but saw as a glass there are no earbuds that sound any good whatsoever these are the kind of the rest in the pocket of your ear they don't have any seal they can't get base and courier basically because they're just too small a hand with enough air they're not sealed and so you end up with the no base on login and this this is pretty good it's actually pretty good right here this is pretty good your your foot but you know the kids they won't base so they're going to turn this stuff up you're going to try to get something happens and they're going to end up with all this stuff really really loud in their ears and that's not good earbuds are just downright dangerous glad I will do that and I'll tell you something for starters rake our old Apple here but by the time their last one came around was actually pretty darn good you might notice that this is a better flatter extension than that sentence just so Anna's got a decent up here but he's still got no base well he came out of the earpods that focus more of the sound in your ear and they actually managed to get from the Roloffs starting a 200 Hertz the roll-off starting at 100 Hertz let the whole octave and that's pretty good so the new half of your paws are really probably are the best your bud that I her permission one of this this is this you and PK one is kind of envision but alright so here's a really bad ones just to a that out howard leight cigna this is the this is actually an industrial headphone that is made for isolating him so it's for work environments but it's a hip bones in a suit listen to music while you're doing it just visible just incredibly screeching right up here just this is the current cost probe or delay you think that was an earbud but it's a full-size feel at home just visible this is the flare audio are one this is nesting headphone it was designed by one of metallica's through some death metal bands before he's here who have idea that this pattern of diffusers behind the public would work really well though any pattern instead is probably going to have some resident frequencies and boy is it got rhythm frequency right there the middle these are just works out alright so I got 10 more minutes in like 50 more slides I'm going to talk just briefly about Square weighs a lot of people normally they talk about square waves is the sum of a bunch of autumn lines and that's true get all the autumn Armani's you put into the proper phase alignment you add this drove of sine names together you get that and then if you add like you know 11 or 12 or minus whatever this to get something a little bit more swear you change the face so that the high frequencies are more advanced and get a little blip on the front end like that you change the ratio so if you have more high frequency energy and not enough over easy energy tableside way to look like that or square way to look like that in any if you want too much slower you can see another hydrogen seen it rounded off square waves to look like that so the point of us where ways is that as frequency response changes the shape of the swear big chains but it's real confusing thinking about square waves and all of our moccasins does that mean that you can our lives that they well there's another way to think about square waves entirely that is like this is switch going to turn on in a colonel I don't care about their maternal okay it's not name of God they analyze it like that but it's not made that it's made by turning something on and what happens is the leading edge how fast it goes up is slew rate lid and that slew rate is going to be proportional to the van past the high frequency response look you know how flat how high something is so how quickly get up a leading edge is going to be totally indicative of the high frequency response and then its ability to keep that energy up there for a long period of time is proportional over time to lower and lower frequencies so when you look at where way you're actually looking at the frequency response in another way the thing is that you add in some phase stuff so you can have to changes in the in this due to the phase shift that where they don't show up in frequency response all of this stuff that you're seeing today is on on the interval t site in the but um on the top bar and a quarter single resources and then goes interpreting business and stuff like that there's Lisa articles that have most of the stuff in here this is a chart that talks about the shape the square waves and what it means I'll draw your attention to this one just because it goes below the zero line like that and this one is not necessarily mean it doesn't have little feetsies back if it goes below the line like that it gives a low frequencies are there they're just out of phase so what this means is this they have plenty of days it's just going to be loose seven days sennheiser bc 800 everything going to the square wave we have a wacko based on the sennheiser 800 which is indicated by the slime ball in here and but we have a credible resolution we've ever seen with JT square waves on the T 1 and the y RT 1 look how absolutely pure and clean this transient edges that transient edge is key for you to be able to tell where sound is coming from if your ears q on time sometime arrival signals and your ears one here that edge very very clearly in order to be able to localize for the sound is coming from well that's the energy so if you have really fine leading edge responds like that you're gonna get by damaging if you have three leading edges on this swirly thing what are you here's trying to cue on what's where's the time if they won't they will confuse them in a class image so the AKG k 71 series headphones has a square wave if it looks a lot like that and pig image very well as well here's the awateh GLC be too and something first of all wow talk about bass response so that's a lot of bass response right there and then they had this in this supreme phaser it has these like double front end things and this is one of those ones where it probably doesn't do too much math exam but it does do some stuff in terms of pinpoint precision imaging same is true with the Sennheiser 8580 that has that turtle front end deter ballooning actually doesn't doesn't harm totally and it doesn't hurt to listen to it's not aggressive but you lose some definition and the image is doesn't image by this big great OBS 1000 people sony NPR v600 the old-school headphone got base one out of phase there and doesn't have a lot of hydrate to response and then I start get th e plus noise but i'ma let you guys just asking questions because I've got like five minutes left and ya got five minutes left so one you guys just go ahead a sequential yeah Barney those will boast I don't have any pictures of it right here and i have i have some i can get out but the most products of their noise canceling headphones are very very very very good they they don't measure particularly well but most noise cancelling headphones part just 34 in terms of the way to bed or they you all sorts of weird things and sound and because it's worth looking at the noise cancelling and this is the line all grass PDF now there early 736 vision idea how many long it's difficult for 25 minutes by doing straight up noise cancelling headphones this is measured passively which is actually pretty good and then the noise cancelling active and this is one of the barriers which we look at the square wave you get pretty weird so the hydrate response and square wit there's some definitely some pretty weird ones audio technically that's shape of the square waves and travel is completely out of phase here so start sewing down and then goes up so it's the treble the Hydra was completely out of a is on that give the noise cancelling circuit audio technica dry skin seems equally ragged-looking also look at the distortion figures right here this while all this should be below this little wine a little one one percent line and a lot of these headphones are going to boulder that this is the bose quietcomfort 25 so this is a bose noise canceling headphone and what you see is that it's got good shape on the on the frequency response it's a dumb question terrible just it but this is not bad shape this appreciate these square waves all these things in so most pretty different noise answers there are there other passing that was not so much yeah there is kind of subtle differences that I used was all native integration it's not an industry standard composition purpose when it comes with that head that I thought was best news I've come to believe that will probably be better use the diffuse field response because it has more that presence region crimes in it I will eventually one of the things I work on this year is turning people to sponsor like people like sent my certain philipson vehicle companies to sponsor the the development of an online tool like a turn pass or you can just say oversee this M on this edge municipal caramel together they live a cocktail and flirting close and very much my do that most important goals in life begins ladies drinking budget born so I gotta convince matters you know maybe software will be good at doing crafts and stuff like offering alright my time is up I was an amplifier ah that was too long to answer okay so wait what is no time my computer you use for your measurements both of these are these are all measured at like less or home so it is very little again all right thank you buddy