Optimal Gain Settings for your Microphone Preamp

there's a lot of misconceptions out there about how to set gain properly a lot of people do it wrong and actually a lot of people do it right and don't know why they're doing it right so we're going to go into some example recordings where i exaggerate the effects of it and you can actually hear why you need to set the gain in a certain area a lot of people have different strategies on how to do this there's a lot of good strategies out there i'm just going to show you my strategy but regardless of which strategy you use there's certain rules that apply so you don't want it to be too quiet because you want to optimize your signal to noise ratio and you don't want it to be too loud because you only have so much room available and if you go over that you're going into clipping and that's going to sound bad so my strategy is super simple i just look at the size of the recorded waveform if it's too loud you can see that it's clipping and if it's too quiet you can hardly see the waveform at all so from looking at the waveform this is about the border of what i would consider to be too quiet i wouldn't want it any quieter than this i would turn up the gain and this is about the limit where i would consider it to be too loud so in this circumstance i would probably turn the gain down just a hair but as long as the visual appearance of the waveform is anywhere in between these two examples you're good now this waveform right here is in between those two examples but it's still fairly quiet and a lot of people will look at that and want to turn the gain up because there's a misconception out there that louder is better you see louder would theoretically give you a better signal-to-noise ratio but let's talk about the signal-to-noise ratio a little bit and i'm going to explain and demonstrate why you don't need to be any louder than this so there's two sources of noise so two different sources of signal-to-noise ratios that you're working with one is from the preamp itself we talked about that the ein the preamp makes noise but seeing as the preamp actually provides maximum gain at all times and you're only reducing the output the actual ratio of signal to noise doesn't change regardless of the gain setting so that signal to noise ratio is fixed there's nothing you can do about it other than getting a better preamp the other source of noise is from the converters the actual circuitry that converts the analog signal to digital the actual amount of noise that it adds is extremely low and better quality analog to digital converters will add less noise but they all add noise so you want to turn your gain up on the preamp so that you surpass this noise from the analog to digital converters and you want to surpass it by a large margin actually the farther you surpass it the better your signal to noise ratio now i'm going to go into detail on this so the test that i did is i recorded an acoustic guitar with actually the same microphone here it's the isk icdm it's a dynamic microphone and typical of any dynamic microphone they have a lower output than most condensers which means they need more gain from the preamp so the first recording i did i had the preamp gain turned all the way down so that there's barely any signal coming out of the preamp going into the audio interface and then what i did is i digitally turned up the gain within the daw to turn up the gain of both the recorded guitar and it's also turning up the gain of the noise from the conversion so let's take a quick look at what i got going on here i've got eight decibels of preamp gain and we're gonna zoom in on the recorded track zooming way in as you can see well as you can't see there's you can't even see the waveform populated here it the the signal is just so weak it didn't even register so we're going to give this a listen so as you can hear there's a lot of noise there the signal is so weak i had to put a lot of digital gain there here's all the gain that i put on there's 24 decibels another 24 decibels and then uh and then 11 decibels so a total of 59 decibels of digital gain that's how low this signal is um yeah that's pretty noisy so i would say that the guitar volume is roughly the same volume as the noise from the conversion so we're going to call this a one-to-one signal-to-noise ratio and i put that right there on the track yeah so if this is a one-to-one signal-to-noise ratio if i boost the gain on the preamp by 11 decibels and then turn down the digital gain here by 11 decibels so that the guitar is roughly the same volume but boosting the gain on the preamp actually boosts the volume by about four times so now we've got 19 decibels of gain on the preamp and our signal to noise ratio is four to one let's give it a listen compared to the first one so as you can hear with a four to one signal-to-noise ratio the noise is quite a bit quieter than the first one and then i boosted the gain again by another 11 decibels so now we're on this track so we're at 30 decibels of gain and that's another four times increase of volume coming out of the preamp so now compared to the noise of the conversion our signal to noise ratio is 16 to one and here's how it sounds [Music] now you can barely even hear any of that background noise this uh 16 to 1 signal to noise ratio is starting to get it's starting to sound pretty good compared to the 4 to 1 and then 16 to 1. [Music] you can barely even hear that noise you can hear it a little bit but it's almost gone as you can see we're still recording at such a low level that it doesn't even register so moving on i increased the gain by another 11 decibels so again that's four times louder so now our signal to noise ratio is 64 to one and if we zoom in on the waveform we're recording loud enough now that you can start to see the waveform just a little bit it's still barely registering but you can see it and here's how it sounds [Music] compared to 16 to 1. so you can definitely hear that the noise is significantly better um there still is a tiny little bit of noise there but it's getting to the point where it's negligible moving on so now i'm at 52 decibels of gain on the preamp again a four times boost of volume so our signal to noise ratio is 256 to one and here's how it sounds [Music] [Applause] [Music] compared to 64 to 1. [Music] [Applause] [Music] at this point the noise from the conversion is inaudible if i zoom in on the waveform well actually even right now at a normal zoom level you can see the wave just a tiny little bit if you zoom in you can see it pretty clearly there we go there's the wave so this is starting to get into the realm of acceptable recording volumes you wouldn't want to record any lower than this because you can hear that like there's a tiny bit of noise i mean it's not much but you don't want any noise at all so and you want to have the best signal-to-noise ratio possible but at some point it becomes negligible that the preamp noise is so much more than the conversion noise that it just doesn't matter and actually anything beyond this kind of gets into that realm [Music] [Applause] so let's take a look at the next one that i recorded again another 11 decibels of gain on the preamp so it's four times louder so our signal to noise ratio now is 1024 to 1. you can see the waveform pretty clearly here and here's how it sounds [Music] compared to the previous one [Music] [Applause] [Music] [Applause] [Music] not really any audible difference in the noise level they're both extremely quiet um and the guitar sounds just as good in both of them so we've surpassed the point where the noise from the conversion is any issue at all um and this final one that i've done this is about the lowest that i would recommend recording at my strategy for setting preamp gain is to just look at the recorded signal so i could look at that and be like yeah that's fine or if i'm looking at a signal like this and be like yeah that's a little too weak i'd want to turn it up until it gets at least to that and as i've just demonstrated this is well above the noise floor of the conversion and the preamp gain doesn't get worse as you turn the gain up the ratio stays the same but the preamp noise is gonna far surpass the noise from the conversion so these are all matched so that the guitar is the same volume and we are only listening to the difference of how much noise there is so i'm going to play the first one and i'm just going to go through them so that you can hear the difference in noise as the ratio of signal to noise gets better so as you can hear it's a pretty negligible difference between the 256 to 1 and the 1024 to 1. most of the noise that we're hearing is actually the noise from the preamp itself and going with a higher signal level then this last one here isn't going to give you any better of a signal-to-noise ratio let's take a look at some electric guitar here that i recorded so this first one this is definitely too hot this is what you don't want to see you don't want to see flat lining anywhere because that's going to cause audible distortion and even all along here like it's still not clipping but there's no headroom like right there it clipped a little bit and then here it's clipping pretty hard this is too hot you want to turn your gain down if your waveform is looking like this this here well this is not too bad but it's still a little bit too hot you still want to turn it down because that almost clipped you want to have a little more headroom than that and right here it actually did clip you see for most of this most of his levels it's actually pretty good but you want to have your gain set low enough so that it works for the majority of the recording and also when they go and play something extra loud like in a loud part you don't clip that's the most important part right there no clipping allowed so if you turn your gain down a little more there we go this is a pretty nice recording level this is about as loud as you would want it so in the normal volume sections there's more than enough gain here to get a good signal to noise ratio and he can go and play loud and there's still lots of headroom even in these loud parts there's lots of headroom that he could play louder and you're still not going to go into clipping this one here you're still way above the noise floor even when they're playing quietly and there's tons of headroom and then even if you set your gain a little higher than this or a little lower than this like this is good and then this one here this is about the lowest setting you would want to go this is still perfectly acceptable um but i just wouldn't go any lower than that like this here this is a little bit too low you're starting to get into the range where the noise floor from the conversion it's not an issue it's still extremely low but i mean you don't want it to be there at all so i would go just a little bit higher than this like i said at least to this so just for reference i also included this one here this is remember the test we did just a little while ago this was the 256 to one noise ratio so you can see like yeah the waveform is still pretty small it's about the same size as this like i i like to record a little bit louder than this um but even if you remember from listening to this like the noise floor here was negligible there was hardly any noise at all so yeah i would recommend setting your levels anywhere between this and this to be ideal i mean this is this one here is not bad like that's not really going to be noticeable that like tiny little bit of clipping like that is not bad but there's no reason for it there's absolutely no disadvantage there's no loss in sound quality from going to a recording level of this here like there's there's just no difference in sound quality from this to this so there's no reason not to record lower so that you avoid clipping that clipping is no good okay another misconception that people have about recording levels is some people say that you should record louder so that it uses a greater percentage of the bits available and using more bits will give you better resolution and that is just simply not an issue and the reason it's not an issue is because you should be recording at 24 bits if you're recording at 16 bits then yeah it's an issue and you should record as loud as possible to get as much resolution as you can but nowadays 24 bit is the standard for recording and 24 bits has way more resolution than 16 bit i'm going to use 16 bit as a reference because that's the standard for cd quality any music from a cd is actually 16 bit and it sounds pretty good well 24 bit has 256 times more resolution than 16 bit so if you work that out to a percentage then 16 bit has 0.4 of the resolution of 24 bit so if you're recording at 24 bit and you're only using 0.4 of the space available you're still getting the bit depth resolution of cd quality and if you're recording at that low of a level you might have problems with your signal-to-noise ratio just from the conversion noise you'd have to be recording extremely quiet to be using less bits than cd quality so if you found this video helpful please hit the thumbs up down there and give this video a like i would really appreciate that also you can subscribe 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Channel: Get.Beautiful.Recordings

Views: 37,795

Keywords: mic, gain structure, gain staging, music recording, how to make your mic louder, how to make your mic louder on pc, how to make mic louder on pc, gain, microphone level, microphone gain, setting microphone gain, how to set up a microphone

Id: PiCQ-2Umuc0

Length: 14min 38sec (878 seconds)

Published: Mon Oct 04 2021