Aux Fed Subs Setup For Behringer XR18 X-Air - Midas MR18

hello and welcome back to the channel for this episode i wanted to talk about oxfed subs using the xr18 there are three main things to consider here one being the xr18 itself the other being your front of house speakers after the xr18 and then the overall concept of oxfed subs and how to use them so let's get right to it with the xr18 and how you would prep it for oxfad subs i'm opening the x air edit software connected to the xr18 if you're already familiar with mixing with subs on an aux with an analog console this is how to get the xr18 to work the exact same way first we want to mouse over to the in out button and click it now we want to tab over to the aux out tab and click it i'm going to suggest using aux 6 as the subwoofer output the reason for that is you're likely going to have monitors connected to some of the other aux outs it makes sense to have monitor 1 connected to aux 1 monitor 2 connected to aux 2 etc putting the sub on aux 6 leaves buses 1 through 5 available for monitors now and in the future so we want to make sure bus 6 is connected to aux 6 on the graph here on the software you can see by the key at the bottom here what the solid color and ring colors mean we want to choose post fader here because we want the bus six main fader to control the overall level of bus six post fader means the xlr output on the front of the xr is after the main bus fader on the selected output this is the default settings of the x air so yours might already look like this if not right click on the one you need to change and that will give you the list option so that you can choose the light blue ring post fader now we can close this window x out and let's get to the mixer screen now choose any channel by clicking on it it doesn't matter which one for this part i'll choose channel one but it doesn't matter you can choose any channel you want to work on okay now tab over to the sins tab you'll see a globe in the top right make sure the globe is highlighted by clicking it when the globe is highlighted it means that the pickpoint changes you are about to make are global they will affect every channel the same this way you don't have to set up the pickpoint on each channel individually what we do on this channel for this setup will also affect the rest of the channels we want to mouse over to bus six and we want to click the post fader option like this we want these posts faded for two main reasons we want our channel strip eq to go to the subs that we're feeding from bus 6. we also want our channel fader to control the level of bus 6. this topic was also discussed in the monitor setup video that's also on this channel for monitors it's generally just the opposite you don't want the monitors to track with the fader but here our subs are front of house so we do want them to track with the channel fader that is why we want to choose post fader on our channel strips for the bus 6 pick point and like i said before since we highlighted the global icon first once we change it here we now change it on every channel to post fader just by making this one channel change these syn changes are now global because the globe was highlighted now if we move over to the right and choose the bus 6 button and we click on the main fader for bus 6 which pressing the bus 6 button should have called up for us that then gives us a couple of things of importance to do here first normally we're going to want the sub bus master fader to match our mains master fader so compare the two and make sure they match depending on your gain structure that could or could not be unity whatever your normal main fader position is you should match the bus 6 sub master fader to it for this demonstration i'm going to assume it's at unity you can click the main left right button and see your master fader level just like this then press the bus 6 button to get back to the bus 6 fader and now you can adjust the bus 6 master fader to match your house fader the other thing is this is how you access the eq for bus 6. after you highlight the bus 6 fader go to the top and select eq that brings up your parametric eq for bus 6. you also have the option to choose a graphic eq via these buttons i typically will just use the parametric the two things i might do at this point are use the high pass filter also known as the low cut and set it to 20 hertz which is almost certainly below the system's low cut off and it might even be a bit redundant depending on what is happening with the rest of your system then i'll take the second filter and have it at the ready for a low end cut should i need to tame a peak if i hear it later in many cases your speaker processing is already going to have done the heavy lifting here already and unless the room is causing something you might not need to do much of anything else on the eq for the low end but if you need to address any low eq this is where you do it the main house eq will not do anything to the subs once you put them on an ox we'll circle back to some of these points later in the video at this point if you put canned music through the system ideally a song that you're really familiar with uh be it a wav file a cd or an mp3 with the channel strip eq flat you should find that setting the bus 6 speed on that channel to unity should be a normal balance between the subs and the mains for the music coming out of your system if it's not you likely have a gain structure issue after the xr so if you hear either too much sub or not enough tops or vice versa and you have no measurement tools available then has a rule of thumb whichever seems normal adjust the other part accordingly at the amp or speakers to balance things so at this point the x air is ready now we need to discuss the rest of your system and how it should be when you're doing oxfed subs normally when we're talking about the xr there is a lot of crossover in the xr and the x32 platform but in this case there's not literally the x32 offers crossover filters in the eq section of some of the outputs what that means is you could have a set of passive speakers and the most basic of amplifiers and could do all of your system processing your crossover functions from within the x32 the xr18 doesn't give you that ability at best it has low cut and high cut filters and those are poor substitutes for the crossover filters that you actually need if you want to do speaker processing from within a mixer but fortunately most of you these days are likely using powered speakers which are handling the crossover functions already or you have amps with built-in dsp handling your crossover functions or maybe you have a rack mounted dsp or analog crossover in your amp rack handling the crossover functions so let's talk about these possibilities the most simple thing is probably powered speakers if you look on the back they'd likely have a mode switch a menu setting or a knob to control roll off for the built-in crossover functionality typically you're going to want your mid-high boxes reaching down to about 100 hertz you're going to want your subs reaching up to about that same 100 hertz hopefully your powered speakers have that ability if so use those settings to start out next make sure all your inputs on your power speakers are set to line input or that you connect to the line input bring an xlr line from the left output of the xr to your left side mid high and bring an xlr line from your right side output to your right side mid high speaker now bring an xlr line from your aux 6 out of the xr to your sub input if you have two subs or more then there's likely a parallel out or an xlr output just marked out run an xlr cable from that sub to the other sub or subs if there is no output on your subs then you'll need an xlr y cable like this to allow you to split the signal between the subs you can either connect this at the xr and run an xlr cable from each side of the y to each sub or you can use this at the other end at the sub input and split from there to the other sub or subs at this point if you're wondering won't my subs be mono well the answer is yes but this is typical i'll include a link to an ev white paper on subwoofers in the video description below mono subs and stereo tops are very typical even for very large setups so not only is this acceptable it's normal okay so now let's address passive speakers in case that's what you have if you have passive speakers but amps with built-in dsp then the above info basically transfers to the amplifiers of their dsp set your mid-high amp at around 100 hertz for the crossover point on the low side and set your sub amp for around that same crossover point for the top cutoff frequency for the subs if you've been running the subs and stereo then you should be able to set the amp in parallel mode that should either be done through buttons or switch settings on the back of the amp or else in the dsp menu itself it's also possible setting the sub amp to bridge mode would be the best option for your particular setup but that would depend on your speakers in your ramp and that's something i can't answer without knowing the exact variables involved still on the subject of passive speakers there is another possibility and that is you're running your system off of a rack mounted dsp like a drive rack or an analog crossover to continue to run your system in stereo with oxfed subs and stereo tops your dsp or crossover needs at least three inputs you need one each a left and a right input and you need an input for your sub feed from the xr if you don't have that you can still run mono with the subs from one channel of your crossover or dsp unit and the tops from the other side but assuming you still want to remain stereo you're going to need to find a way to create that third input for the subs with some extra equipment one way is to add another crossover or dsp unit and just use it for the subs another way is to get a new sub amp with dsp built in and then it can do crossover functions for the subs from that new amp in either of these cases your subwoofer aux output from the xr would directly feed this new input while your left and right would feed your existing inputs like always this is where the x32 and its built-in crossover filters would have allowed you to do this directly from the console and no new equipment needed i'm sure someone is thinking what if i just use the low cut and the high cut on the parametric eq that would work but not optimally those filters aren't nearly as steep as a proper crossover filter which is what you would want for this application here is a quick example of the steepness of a crossover filter like we would normally use for this application versus behringer's cut filter you can see the difference in the slope of the filters with the proper crossover filler being steeper so we've talked about prepping the x air we've talked about your amp speakers and crossovers now let's talk about some of the concepts and tips for using oxfed subs you're now effectively going to have two main faders to think about your main fader and your main bus six fader which is your oxfed sub fader they should in theory normally be matching and level assuming all your gain structure is correct if you turn the mains up or down during the show then you need to match that with the sub fader because your subs will no longer track with the main house fader a caveat would be unless your ears tell you that you needed more or less of one or the other trust your ears but don't forget your meters and settings as well another thing you'll still want to use your high pass filters or low cut as behringer calls it on your channel strips just like normal and you'll still want to use your typical eq settings in other words you don't want to use the aux in place of the low end on your channel strip equalizer what you're trying to do with the oxfed subs is simply send only low end material to the subs that means the kick drum will be fed to the subs the deeper toms to the subs the keys the bass guitar but not things like high toms or cymbals or guitars usually or even vocals especially vocals where has the high pass filter causes a fairly general slope of low end and a channel strip getting to the subs the oxfed method is much more abrupt if you don't turn the ox or bus as the console calls it up on a channel the nothing from that channel is getting to the subs that also means that all that low end stage wash that random open mics like the vocal mics will normally pick up won't be getting to the subs either you're effectively removing low end mud from the subs this way essentially the only things getting to the subs are the things that you choose that need subwoofer reinforced low end extension and you control that with the channels bus 6 sin control so with that said you might wonder why it's still important to use your low cut filters and your low end channel eq not only is it just general good practice but there are several things to consider here for one there could be times where you're using your low-cut filter higher than what your sub cut-off actually is symbols could be one example of that we're live you might use the low-cut as high as 400 hertz on the console for the cymbals another reason is for recording or streaming if you're recording the mix post eq or you're sending a mix to a stream if you're ignoring your low end on the channel strip and overcompensating in the house with the bus control your recording or stream won't hear the low end that you expect it to have one of the negatives of oxfed subs is you risk system balance you've unlinked the subs from the tops and you're now totally in control via the ox what that system balance is in the house if you overdo it the mix you hear in the house will not be the same as the mix in the console now let me explain that a bit one of the easiest examples of that is what i just said about your post eq recordings one of the typical questions you'll see on the forums is when someone has switched to oxfed subs and now their base and kick are weak in their recordings the answer to that is they're pushing the oxmoor instead of properly eq'ing the kick itself they've essentially broken what the room is hearing from what the console is doing more than just dealing with stage volume but the easy answer to that is keep in mind what i said about not changing your normal eq approach do a few test mixes and recording to get a handle on the changes you're experiencing also it never hurts to compare your mix in a nice set of headphones versus what you're hearing in the room if the mixture hearing in your headphones is too weak on low end that tells you you're pushing your subs on an ox too much recalibrate things by finding a happy medium you don't have to sacrifice your stream mix to improve your house mix of course one of the benefits of oxfed subs is just how much control you gain on exactly what instruments get sent to the subs and what do not get sent to the subs also getting that stage wash that unwanted low end from the wrong places out of your system out of your subs can really help with clearing mud from your mix all right please like and subscribe if you found this useful i'm going to leave some links to some other videos here and as always put any questions comments or video suggestions down below and i will see you next time

Channel: Alan Hamilton Audio

Views: 22,224

Keywords: Aux Fed Subwoofer XR18, Aux Fed Subs Method, midas mr18, aux fed sub technique, Aux Fed Subwoofer Setup, Aux Fed Subwoofer X32, behringer subwoofer setup, XAir XR18, Behringer XR18 tutorial, Behringer XR, X-Air Edit, Midas MR12, x-air, Beringer, Live Audio, behringer xcontrol, Berhinger, Behringer XR12, X-air tutorial, Live Sound, sound reinforcement, sound reinforcement training, church audio, Church sound, live mixing, digital mixer, Subwoofer tutorial, Subwoofer setup

Id: ZBXaR2W2E1I

Length: 16min 43sec (1003 seconds)

Published: Tue Jan 05 2021