MIDI Part 1 - MIDI Signal Path

hey folks its Andrew Kilpatrick here and today I'd like to talk about MIDI and specifically I'd like to start a series about MIDI that I hope will continue I have a whole list of topics that are a lot too much information for one video so I thought I'd start at the very beginning this is going to be called MIDI part 1 and cover some of the basics and then get into some of the more nitty-gritty details as time goes on and so why would we want to know about MIDI well believe it or not MIDI exists in pretty much every music and audio product whether it's software or hardware and it is in there somewhere whether we can see it or not so MIDI is used and the the design of MIDI effects a lot of the things that we use in music production and audio production so I've always been of the belief that knowing at least a little bit about a technology is a good way to make better use of it because we know what its capabilities are we know what its limitations are and we can we can make better use of it knowing those things because we can sort of maximize the potential so if you use music software or audio software if you use especially music hardware like synthesizers and drum machines and things like that those things are all MIDI based and being able to know how they work will help you to get the most out of it so I've prepared a slide for each episode this is the first one I'm just going to show you the topics that we're going to cover and then I'll get into some of the details so let's call this MIDI part 1 this is MIDI signal path I'm going to give you a quick introduction then I'm going to talk about the types of MIDI and then I'm going to talk about the terms in out and through which are often misunderstood and shouldn't really be and then we're just going to quickly cover at the very end something about merging and splitting MIDI signals because that's something that happens kind of in a lot of devices that we use so let's go to the bench and in my typical style I'm going to sort of do this with a pen and paper because I find it's just easier to sort of explain with a bit of hand waving and and and drawing so quick intro let's talk about MIDI I started using MIDI back in the mid 90s as a musician I was using MIDI on a Windows 3.1 computer running cakewalk controlling some external synthesizers that I had and back in those days if you didn't really understand even the basics of MIDI you wouldn't get very far so most people back in those days had books or read the manuals that came as equipment often had a introduction to MIDI and and things like that so it was pretty easy to learn about the low-level details of MIDI also software did a much better job at exposing the MIDI protocol and specific things about MIDI to the end user because the software was simpler and it was handling MIDI on at a more basic level than today a lot of modern software I find tries to hide a lot of those details behind the shiny gooeys and now that people are getting more interested in hardware especially hardware connected to their computer like modular synths and external synthesizers and things that's becoming popular again a lot of the software is actually trying to play catch-up I would say and sort of go back to more of the old ways of being able to expose a lot about those protocol details so that we can actually have the proper control over our devices again so I kind of feel like we've come full-circle I would really prefer just to use a program like my old cakewalk software from the 90s but but that that's the way it goes so let's talk about how many works from a very very high-level perspective so that we can make sure we're all on the same page and know what we're even kind of trying to do here so let's talk about a typical modern example we've got our computer right here this is let's just call this our DAW this is running you name it whatever doesn't matter which type of software you want to use we've got our controller keyboard here this doesn't make any sounds it's just got keys on it and it's connected to our computer via USB or whatever doesn't matter over here we've got our synthesizer module this is like a desktop synth doesn't have any keyboard on it so let's ignore just specifically what these lines represent at the moment but let's just say there's MIDI signal somehow traveling between here and here so how would we normally use this in a modern setup let's say we're doing all our sort of our sequencing and our recording on our DAW we've got our controller keyboard we're going to play notes there and when we do that we expect that our synthesizer let's say our synthesizer has a pair of headphones attached to it so we can hear what's going on and we play notes here and we expect to this synthesizer will do something so what's really happening when that's happening the signal from the synth of this keyboard this MIDI signals going into our DAW it's probably going into a track that we have selected and then the output from that track is being sent over to our synth and then we're hearing the result if we record and then play it back this part is out of the picture now and now it's just the DOS still sending the MIDI to this synthesizer but we might have another synthesizer this has a different front panel has these different shapes on it whatever and now we actually want to go to another track and assign this one and we want the output from this one as well as this one I don't No we've need another pair of headphones or something here but anyway now we've got one keyboard and we're going to select which one of these we're going to control and that's all handled within our da da magical Erie routes things and sends the signals to the correct place we could even use this keyboard obviously to control software instruments that are built in here but inside the DAW there's some MIDI things happening that's moving the signals around and sending them where they need to go so this is a very typical sort of example involving a computer another example would be lets say once again we've got our controller this time the controller is like a drum pad and over here we've got a drum machine and we want to play the drum machine sounds directly from our drum pad because maybe we're performing there's no computer involved in this case in this case let's call this a MIDI cable because this is most likely what it would be so we've got our drum pad here we're playing it with drum sticks and MIDI signals are being sent over here and our drum machine is playing back its sampled sounds or something like that so these are typical examples of how we might use MIDI in a real situation now let's talk about the types of MIDI and some aspects about that because this is something that's often a bit misunderstood types sorry about my writing types of MIDI okay I'm going to cover three types of MIDI that are kind of the most common things that you'll see when you're connecting between different devices as I said before MIDI also exists sort of inside software and that's a whole other topic for another discussion but basically we have din MIDI we have USB MIDI and we also have Network MIDI this is a little less common although there are people that are doing a lot of things with it when when you have a complicated studio okay den MIDI that's this is the one that everyone kind of recognizes this is kind of the de facto shape of MIDI when someone thinks what what is MIDI it's this thing it's this five pin plug and only three of the pins are used actually the center of three pins and this is kind of the traditional MIDI connection this came out in around 1983 I actually have a synthesizer which you may have seen during the intro Juno which is leaning up against the wall and it was probably one of the earliest not the earliest but within the first few years of MIDI synthesizers it was sort of in that first generation and I actually still use it all the time with all my modern computers and gear and everything and yeah still happily ticking right along using these kinds of connections this is really slow although it's designed in a way that makes MIDI ax is designed in a way that makes the speed limitation not as much of a problem as people would think it runs at thirty 1.25 Killah bits per second which is pretty slow like the speed of a dial-up modem or so then we've got USB MIDI now what I've been showing you off the off camera here is this the connectors on this thing this is a roland um one I use this all the time and it's a pretty good MIDI interface and it actually has two of the three kinds of MIDI that we're talking about right now it's got the den MIDI these kind and it's got USB this is just a regular USB a connector and it actually has two MIDI ports in it one goes in and the other one goes out so USB MIDI came around late 90s it's actually part of the class there's a standard class compliant MIDI class around 1999 I believe is when the class was made it runs at 12 megabits per second but not really because there's USB stuff that happens but anyway it encompasses all the same things that are part of this MIDI but it puts it over USB and we'll talk about that in that in a later episode talking about the actual details of how USB MIDI works and then there's Network Committee which I'm less familiar with I know there are a few different implementations a more popular one from what I understand is called RTP MIDI you can do it over any kind of connection RT bidding RTP MIDI is I believe is what Apple uses if you do IP MIDI within Mac I'm not a Mac user so I don't know the all the details of that there's also another way to do MIDI over a network over Wi-Fi or Ethernet or whatever not OSC OSC is misunderstood and when it came out a lot of people were like oh it's the MIDI killer this is going to be it for MIDI but in fact if you read the OSC spec you'll find that they don't actually replace anything that MIDI does in fact when it's time to do MIDI eat things with with OSC they just allow you to put MIDI over OSC it's just the same protocol that you'd get on here except they just put it in an OSC message so let's just all be clear OSE doesn't replace MIDI it encapsulates MIDI and then adds more things okay now let's talk about the most misunderstood concept about MIDI which is in out and through through spelled like a drive-thru in out and through okay this is the most annoying part of MIDI as unfortunately as much as I like Roland they make devices like this and they're not the only ones that have misleading terminology printed on these connectors this says connect to MIDI out but what it should just say is in because that's there's an arrow actually pointing in this is where a MIDI goes in this one says connect to MIDI in whereas it should say out because this is where MIDI comes out and this is a really really dumb that companies have decided to sort of change the way that we talk about things because if you've ever used audio equipment inputs and outputs don't aren't aren't that big of a deal in MIDI we just call them in and out not input/output but on audio equipment it's just inputs and outputs we always know that audio comes out of an output and goes into an input so it's the exact same with MIDI and one thing to keep in mind about MIDI is that it's unidirectional that means that MIDI only goes in one direction and in fact a MIDI interface like this is actually two different MIDI interfaces one goes in and one goes out in fact there's two LEDs here one showing each direction and there's two cables on the one end and there's actually two ports running over the MIDI the USB cable when it shows up in your computer you'll actually see an in and an out it's actually two things so in out and through this is really good that we have this and we should just call it what it is ins take signals from outs and now it's plug into ends that's pretty straightforward so here's an example of why this is an interesting and useful thing let's say we've got our DAW software over here on our PC or our Mac it's connected to our um one they spelled it out like a word and we've got the two plugs on our MIDI interface like this let's this is the out and this is the in so let's just start with the out first we've got our da we're going to play a sequence on our dog we want it to drive our external synthesizer here's our synthesizer box that we had on our last screen there our last page when I press play in my DAW it sends signals out the out and our synthesizer plays along with our song that's great so what is the dog know the dog knows obviously the existence of the UM one because it's this is USB here and this is MIDI over here obviously it knows about the UM one because it's detected the MIDI device in the computer the DAW software doesn't really deal with MIDI USB devices it directly but it's detected the MIDI device it's like oh I've got um one I've got an out in an in so it knows it's sending data out through there this is coming out the MIDI out controlling our sent but the DA doesn't know what synth is connected there's no way for it to detect this synth or do anything to it in fact we could unplug this while it's playing and the dog won't know any anything different and that's I would say a really good advantage of the way MIDI works because you can configure things however you want in your studio and your software is not going to try to rearrange stuff and do crazy things as long as it sees the same MIDI interfaces connected it will pretend like it doesn't know there's there's a difference you could unplug this you could plug a different synth in while it's playing it doesn't matter and it will respond accordingly there's it this and that gets us into our next point which is through what do we do within let's let's talk about in first I think that's important so we've got our old MIDI keyboard here this is not a USB keyboard this is just a regular MIDI controller keyboard or an old synth that hasn't a MIDI out when we play a keys on the keyboard the out port will generate MIDI events and we can connect that to the in on on our um one this would just normally go right into the back of this keyboard and now when we play notes our DAW will see MIDI events coming in through the USB MIDI interface and that's cool now we can play notes and loop it through here just like we had on the other on the other page and we're going to control arson or hardware synth or our software synth for that matter with our keyboard but let's say we only have one um one and let's say we actually have two of these since or are different since this since this is a drum machine like we had before and we also want to control our drum machine from the same um one but unfortunately we've already used its port over here what can we do this is the import here most since have an in/out and through so the third connection is the special one in and out we know what those do that out will make MIDI events the end will take MIDI events but the through will give us a copy of the in events the out have nothing to do with the through and the reason we have through let's put the through on this end is so that we can daisy-chain the MIDI this is the in on our drum machine so we can daisy-chain the MIDI to multiple devices and in fact if this device has a through we could daisy chain it to another device and so on and that basically allows us to use one port to control multiple devices now there's obviously limitations to this because if this synthesizer uses all the MIDI data that's coming in well then we're going to have a little bit of trouble we're going to have to configure things so that there's some data that this can use by itself so a lot of for instance multi tamara scents that respond to every channel and every note coming in obviously we would have to configure that so that we could have a channel left over for our drum machine but there's other kinds of MIDI events let's say our synthesized our only cares about notes but we also send MIDI clock well our drum machine maybe it doesn't care about notes maybe it only cares about the the MIDI clock because it's going to play and sync with our DAW so this is a typical example of how you would use a through-through is literally an electrical copy of the inn it gets buffered again so that the signal is strong and has sharp edges again which is good you can daisy-chain this multiple times not infinite number of times there will be some electrical distortion that happens if you do it too many times and that would basically eventually cause data errors and things like that but for practical purposes this is a totally valid and it's what it's intended for actually to to to be used so this is a typical setup where we're using in/out and through and the very last part of this episode I'm running a little long on the time but let's just get through it is to talk about MIDI merging and splitting merging I'll just put it at the bottom of this page merging and splitting so this is more of a collage achill thing in terms of how it's actually done but it's a physical thing in how we would configure our our systems instead of daisy chaining through here not all since to have a through port especially smaller ones they sometimes just omit that connection so splitting would allow us to instead of going through let's say instead we're just going to rub that out let's say we would connect this to a box a MIDI splitter box split that has multiple throughs so this would be like through it's essentially just the through with no sense inside or multiple throughs through through through now we could connect this to each device separately so this could connect to here this one connecting to here this one could connect somewhere else and this will just instead of dated chaining the signal just provides a different sort of way of wiring up your studio and the good thing about that is let's say we don't want to use one of our since or we took it to lend to our friend or what's turned off it doesn't need to be on for for this connection to work it also helps with this problem of the signal distortion if we change through too many devices and so on MIDI merging is kind of the opposite of splitting that would be a situation where let's say we have our our keyboard here and we have our drum pads here and we want to connect them both to a synth at the same time so we have our merge box here and then this is connected to our since so in this case we take two different signals and we add them together to generate one signal to go out to our device these are less common this is very common in software actually it's always happening in various software where we're taking different signals for instance when you play back a track in a DAW and play your your keyboard live over it that's merging that's happening in software in hardware not as common still useful though and there's some specific details that this merger kind of has to be aware of how MIDI works so that it can combine these signals in a way that makes sense anyway that is let's call it episode episode 1 MIDI part 1 and I hope that you enjoyed this if you did then please subscribe because there's there will be more episodes coming soon I have a list of topics and so this is hopefully getting everyone on the same page so we're all kind of speaking the same language and I hope that you maybe learned something from this so far please leave your comments and like the video if you found it useful and and hopefully you'll join me for for the rest of our adventure I'm sure we'll all learn something and have a good I'm thanks a lot see ya

Channel: Shiftedphase

Views: 57,122

Keywords: MIDI, electronic music, synthesizers

Id: 5IQvu8zlmJk

Length: 24min 28sec (1468 seconds)

Published: Mon May 22 2017