How to get clean analog audio from a Blue Yeti microphone into a Sony a6400 camera using a Raspberry Pi Zero

Clean audio = clean USB power

You can connect the headphone out of a Blue Yeti microphone into the mic in of a Sony a6400 camera but the quality of the audio you get will depend on how clean the USB source powering your Blue Yeti is.

In order to get analog audio into your camera from a Blue Yeti, you need to plug the Blue Yeti into a computer¹ via USB and into your camera via an auxiliary cable. When I did this with the Blue Yeti plugged into a USB hub connected to a MacBook, I got quite a bit of noise, even after turning the input volume down to 1 on the Sony a6400 (which you should do).

When I tried plugging it into my daily driver development machine (a StarLabs LabTop), the noise was unbearably loud. Then, however, when I plugged it into an old MacBook Pro, the noise was almost gone. So I thought I’d give it a try with a Raspberry Pi Zero and ­­— lo and behold – silence. It’s the cleanest USB power for a Blue Yeti that I’ve been able to find yet and it doesn’t hurt that it’s a $5 device.

Step-by-step

So, in case you have the same problem getting clean USB power from your existing devices to power a Blue Yeti microphone with a camera like the Sony a6400:

1. Get a Raspberry Pi Zero (with the official power adapter² and a good quality Micro USB male to USB A female adapter) and plug it in.

2. Turn the volume in your Sony camera down to 1 (Menu → Movie 2 → Audio Rec Level³).

3. Turn the gain on your Blue Yeti down and turn the headphone volume to somewhere half-way (you can tweak it using your level indicators but better to start lower and go higher rather than give yourself a loud shock).

4. Plug the Blue Yeti headphone out to the microphone in of your camera.

5. Plug the Blue Yeti USB out into the USB in on your Raspberry Pi Zero.

And that’s it. You should enjoy beautiful, clean audio with your Blue Yeti and Sony a6400⁴.

That should do it!

To see a live demonstration, watch today’s update, embedded above. A transcript of the stream is below.

Transcript

Hello and welcome to a special update you might have noticed if you watched the last few S’updates or the last Small is Beautiful that we did this week, this past week, that my audio was out of sync. In fact, if you’re paying attention right now, my audio should be out of sync. And I want to show you how I fixed that, how I found out what the problem was and how I fixed it. So let me show you, first of all, I’m also going to put on these headphones so I can hear what you’re hearing from my monitor over here.

So, all right. Now I can hear myself. The audio is fine. This is in terms of levels, et cetera. And let me show you my setup just slowly over here. Wait a minute. Actually, let me switch it up first, because I had it really nicely placed there. There we go. Let me pick up the camera now. So this is my setup and lots of screens. I know.

And in terms of the audio, so I have a Blue Yeti microphone up here and that Blue Yeti microphone, I’m going to stand up here and try not to snag my headphone cable off, has a USB connection here and a mic connection. And you can see apart from also it’s quite dusty. You can see that they’re both connected. What’s happening is I’m using the USB for power and I’m actually getting an analog signal out of the the headphone jack over there and where those are going to…

So if you look over here, I have a USB hub and this is the power coming in. So that’s just providing power to the Blue Yeti. Now, you can’t connect this to any power source. It has to be a computer. The Blue Yeti is very peculiar about that. And the headphone jack, if you follow that… is connected to the back of my Atem Mini Pro into the microphone input over here.

And now if you look at my Atem controller here, you’ll see in the settings that it’s the mic is set to line. OK, that’s important. I’m not going to put it on microphone right now because it would deafen you, but the headphone jack provides a signal that’s a little lower than line usually, but it’s still much higher than microphone powered like a microphone with power would be providing.

So that would be very, very loud if I switch to that. Now, the problem is and you can see that the sync is off, I’m assuming I can’t see that right now. But I’m assuming if you’re watching this, my lip sync is off. And that’s because let me show you my camera over here. So the video is coming out of this Sony Alpha 6400 and it’s coming out via HDMI that you can see over there.

So the problem is that HDMI has latency, all HDMI has latency. So the video is coming in slower than the audio. And that’s why there’s no lip sync. Now, with the Atem Mini Pro – with the app – which I’m running on a MacBook over here,

you can actually set the latency. So I can… if I go over here, over here, I can actually add a delay so I can add, I don’t know, let’s say [stuttering audio] four frames of delay, which is now making it very difficult for me to speak when I hear myself, because it’s coming in four frames delayed. So I’m just taking the headphones off. Now, this may or may not fix the problem. I am going directly from my microphone source in the mixer and previously four frames of delay is what I arrived at experimentally.

But recently something happened. I don’t know what it was. And I’ve done some tests and it seems like maybe when chroma key is on, the delay is different. Maybe this latest version of the the software has actually fixed it. I don’t know, because I only just updated. But the problem really is that this is not the way you should be doing it. Right? And so why was I splitting this up? Why was I taking… or why did I decide that I should put, like, the audio in directly to the mixer instead of into the mic ­– into the, sorry – into the camera, which is how I could have done it.

And that’s because when I tried it, I just got horrible static and horrible noise and I tried to narrow it down back then when I first set it up and I didn’t have time, so I was like, OK, I’ll do it like this. And then Atem came up with the delay and it was OK. So I’m going to turn that delay off again. So that will…

[stuttering audio] and there we go, the delay is zero now on my Atem controller… you can see over here the delay is zero. And let me show you what happens if I just plug the… instead of the line in… So instead of plugging it into the Atem, if I plugged it into the into the camera directly, let’s see what happens now.

I’m also going to… over here… momentarily… Let’s see. Let me put my headphones on as well just so I can hear what’s happening. OK. All right. So for one thing, I do have the audio levels on the camera. Let me try and get that here. The audio record level is set all the way down to one. OK, so when I do the switch, hopefully it won’t it won’t deafen your ears.

I’m taking out the audio. So are you going to lose my audio momentarily… [silence]

OK, and I just plug it in to

to the camera and you can hear it. I mean, it’s I’ve turned it down the doors. You can see on the on the camera, if I like to show you this, if I go to the menu, your record level, you see it’s that one. And if I’m quiet for a second…

You can hear that sound, right? If I actually turn the audio level up…

OK, so that’s the that’s the buzz that we’re getting and this is terrible, terrible audio. Of course, it’s terrible audio, but if you are watching now my lips, that should be in sync because, of course, the audio is now coming through the HDMI and it’s synched in the camera and it’s coming into the mixer. And at that point, it’s it’s mixed. So there’s not going to be any lip sync issue.

This is how you should be doing it. Now, this is not the horrible audio you want now. I mean, we can try and make it a bit better. So it’s much louder, of course, because remember, it was set to line on the other one. So you can… what you can do is… let me show you you can try turning down the headphone jack over here. And now that should be a bit better if you can still hear me. And also, there is, of course, a gain at the back of the… of the [Atem] let’s see…

Let’s try to get that in there. There’s a gain and you can turn that down as well. All right. So but this is not great audio by any means. You can hear that terrible humming. So I was like, OK, why why is this humming happening? And so today, what I did and I’ll do it now, it’s got to do with the USB connection with the power connection over here. So it’s got to do with this.

So what I tried was, OK, oh, it’s gone to sleep again. So let me turn this… or is it just… [wakes Mac from sleep] ok, there we go what I thought was OK, so what would happen if I changed… If I unplugged…the I wasn’t using this USB hub, but I plugged it into this old MacBook Pro, Laura’s old MacBook Pro that’s just lying around here. So look at what happens when I do that. You’re going to lose my audio for a second again and then it will come back. [silence]

All right, so now it’s being powered by the MacBook Pro. And can you hear that? That’s actually way better! There is it’s not the same sort of

the same sort of noise that we have. So if I go over here onto the camera and I just turn up. The audio level…

You can see you can hear when I turn it up…

There is some, but… It’s not… and of course, it’s going to be clipping.

But that is so much better, so, OK, so that was the “aha!” moment. All right, so this has to do with how much noise there is, how clean the USB connection is. So it’s it’s electro

electromagnetic interference, basically. So I was like, OK, I’m not going to use a MacBook Pro for this, not least of all, because that MacBook Pro, even if it’s just on at some time, sometimes the fan comes on and that’s really loud. So I was like, OK, what is? And again, you can’t connect it directly to just a USB power source. It needs to be a computer or the blue yeti doesn’t work. So it’s like, OK, what’s the simplest computer that I could have that’s also silent? That’s also really well built and shielded.

And that is what brought me to try…

the. Raspberry Pi Zero. So this is a Raspberry Pi Zero, one of a couple that I have hanging around that I was playing with and I was like, let’s try it with that. Now, every component matters in terms of the noise. And this is connected with the official cable, to… that’s actually an iPhone (or an iPad) power adapter there. I tried it originally with with a Raspberry Pi 4 with the original Raspberry Pi power adapter.

And that was very, very low noise as well. Much lower noise, actually, than the MacBook Pro. So I was like, OK, I hope it works with the with the Raspberry Pi zero as well. And spoiler: it did! So let me just show you what it’s like with that. But also remember, every component counts. So this cable here, for example, if I was to use so this cable here is where I’m going to connect the USB from the Yeti.

But I also tried it with this sort of cheap adapter that I had and there was a lot more noise with this. So every component really matters. So again, we’re going to lose audio for a second, but hopefully for the last time and I’m going to unplug the USB from the MacBook, oops that’s the power… [silence … struggles to plug in USB with one hand]

Right. OK, so I’ve just plug it in, that is that is harder to do than it looks with one hand to push you, apparently beyond my capabilities. All right. So…

Now, that is connected to a Raspberry Pi Zero and that is connected to power, so the Blue Yeti is on, and I have my levels. What’s interesting is I found that the levels are lower. So I’m just going to say, OK, here we go. Actually, there we go. Let me let me just adjust this… Oh, of course, the gain… is up so the levels are lower. So what I can do… is… I can turn the gain…

All right, wait a minute, sorry, let me switch to the camera so you know what I’m doing, I can turn the gain almost all the way down over here. Now, you’re not going to hear me very well. I’m just I’m very close to the microphone right now. And what I can do is I can then use… here… Let’s switch to this… I can then adjust the volume over here that I’m getting.

And and that’s pretty good. OK, I’m in the reds a little bit. So if you look at my monitor, you can see my levels. But I’m going to stop talking for a second and I just want you to take a look at those levels there, OK? [silence]

And that’s how little noise there is with the Raspberry Pi Zero with the Blue Yeti connected to the Raspberry Pi Zero. So again, I’m just doing this all live. So these are… not I’m going to get the levels just right. But that, in a nutshell, is how I’m going to be doing things from now on. And that should solve the lip-sync problem completely. And, yeah…

I can turn the mic off from the Atem Mini Pro and. Yeah. So it should be going in, synchronized into the Atem and this… So the real thing is that this little… If you’re having the same issue, for example, get a Raspberry Pi Zero. Get the official connector and everything, it might be a few bucks more, but just get the good stuff and I think this cable was from Pimoroni, I’m not sure in of their sets or I don’t know if it’s just a Raspberry Pi official cable, I don’t know…

But just get all good components for it, and, uh…

That is how you can get very, very clean audio out of the headphone jack and into the microphone, jack of the computer, and that way you you won’t have any audio sync issues whatsoever. So I hope you found this useful. And this has been a special little S’update, today, Sunday, May 23rd, 2021. Take care.

Be well. Bye bye!