Stumped by white noise - Behringer 302USB

[macnmotion]

Hi. I'm stumped by the following. I'm using the following equipment:

• Behringer 302USB Audio Interface (new)
• Sennheiser EW100 G3 Wireless Lavalier Mic
• Audio Technica M50X Headphones
• Mac Studio M2 Max

I already owned the Sennheiser mic, so thought I would try to use it to learn the interface and practice audio for my live streams. The interface seems pretty simple to set up. Since I don't yet have an XLR mic, I've plugged in the Sennheiser mic into the 3.5mm mic jack, and my headphones in the 3.5mm headphone jack. When monitoring the setup with the headphones I get background white noise when the mic is plugged into the interface, but no white noise when the mic is unplugged. However, when I record with the mic and headphone plugged in, there is absolutely no white noise on playback. The white noise is only present with live monitoring through the headphones and only when the mic is plugged in.

I can work through it I guess by ignoring the white noise while monitoring (or by not monitoring at all) since the recording is clean. But I'm wondering why the white noise is there while monitoring -- am I doing something wrong? Any advice is very much appreciated.

 

[ecc83]

At first I was going to say "there ain't no freakin' 3.5mm mic input!" and are you plugging into the mic jack on the mac? These CAN be noisy on PCs and I doubt Apple use much better pre amps?

But no, I think you are going into the mic input for a headset on the mixer? If so I am sure that is where the noise is coming from. I don't know anything about that lavalier mic but think it is a poor level match for the Behrry Hset pre?

Now, I have owned a variety of Behringer kit and always found their (XLR!) mic pre amps to be very good. I have here a 1202 mixer and the pre amps in that are entirely comparable to the ones in my MOTU M4 interface...i.e both very low noise with adequate gain. I had a UMC 404HD and again the mic pre was very good, speech with an SM57 easily possible.

So, summing up, I think you have hit upon an unfortunate combination of components and strongly suggest you get a mic that will plug into the mixer's* XLR input. A dynamic will have to be worked quite closely, no more than 100mm say but any capacitor mic will allow 300mm+ operation but do remember that this increase ambient noise pickup and "room effect".

*These very basic budget USB mixers used to suffer an inherent "whine" noise due to their 16 bit operation. Maybe the 302 is a later, better design? In any case the noise can be mitigated to a great extent. Cross that pont if we need to!

Dave.

 

[macnmotion]

Dave, thanks for taking the time to respond.

I researched this stuff for almost a week, watching 10s of videos about the mixer and various microphones. My intention was to purchase that mixer with a Behringer XM8500 mic as an entry level way to learn this stuff, with good enough output for my purpose (live streams of views from my microscope). The combination of XM8500 and 302USB is proven to work together well based on my research, and the XM8500 gives similar results to the Shure SM58 at a lower price. While I was finally able to source the mixer, I have not been able to find a reliable source for an XM8500 here (in Thailand). As you might imagine, there is a lot of counterfeiting here, moreso of Shure mics than Behringer but I still was hesitant purchasing from a non-store online source. Also note that prices here don't mirror prices in the west, so while this would be a small risk purchase in the west, it's a bit more of a risk here - also I just hate being screwed. I already had the Sennheiser mic in hand, so I figured that would at least get me started quickly - I had seen videos of gamers successfully using their headsets with the 302USB without reports of white noise, which is why I was surprised when I ran into it.

You're probably right, just an unfortunate combination of components. I doubt the issue is with the headphones, but I can plug in some other headphones tomorrow to rule that out. I was hoping to use the Sennheiser until summer when I will visit home in the USA where I can purchase the XLR mic of my choosing, but I'm leaning toward finding some other XLR mic here -- I can purchase a Shure SM58 from a trusted source however it just sucks to pay 250% the cost of one in the states. I'll update this thread as I continue investigating. Again, thanks.

Andy

 

[ecc83]

You are most welcome Andy! This mic https://www.amazon.co.uk/SoundLAB-Dynamic-Switched-Microphone-XLR-XLR/dp/B00F58V73Q
uses the very same capsules as the 8500 and AFAICT sounds just the same!
Unfortunately the ad is telling porkies, the supplies cable is NOT an XLR mic cable but an unbalanced XLR to jack plug so you will would have to get a mic cable as well if you can source the mic. Shame you are so far away, I have SHEDloads of cables I shall never use now.

But I have plenty of time on my hands so feel free to ask if you need more help.

Dave.

 

[rob aylestone]

I'm totally confused by how this is connected? I'm assuming you have the usual Sennheiser half-width receiver with XLR outs and these are going to the interface? Where are you plugging in the headphones - the mixer? Any chance of a little rough drawing of how the gear is setup?

 

[ecc83]

I'm totally confused by how this is connected? I'm assuming you have the usual Sennheiser half-width receiver with XLR outs and these are going to the interface? Where are you plugging in the headphones - the mixer? Any chance of a little rough drawing of how the gear is setup?

You've got me wondering now Rob! Yes, if Andy has the receiver why not just go into the XLR input of the mixer? I confess I have been able to find nothing about that lavalier microphone.

Dave.

 

[macnmotion]

You've got me wondering now Rob! Yes, if Andy has the receiver why not just go into the XLR input of the mixer? I confess I have been able to find nothing about that lavalier microphone.

Dave.

I'll send a photo in the morning.

 

[macnmotion]

Here are a few photos that might help to explain my current setup. The wide angle shows all components involved. Then I include a closeup of the mic transmitter and receiver, and also of the behringer USB302 so you can see the 3.5mm jacks I'm connecting my headphones and mic to. The 3.5mm mic port is controlled by the two knobs all the way to the left. The mic is not an XLR mic, we originally purchased it to use connected to a DSLR recording interviews years back. It's been sitting in a cabinet unused for years so I thought I'd give it a shot with this interface.

I have some shops looking for a couple other options of entry level XLR mics - I'll see if they have something in stock.

 

[macnmotion]

OK I have a Rode PodMic XLR microphone ordered, I should have it in a few days. I'll follow up here once I can test that mic out with the Behringer mixer.

 

[macnmotion]

I will continue updating this thread in case some other newbie might learn from it.

While I have ordered an XLR mic, I think I could have solved the white noise with a software solution, and in fact I think I'll be using this software solution even when I get the XLR mic. I have installed BlackHole for Mac, and I'm using it to control the input and output devices on the computer. Instead of using the Behringer 302USB to mix my voice (mic) and background music (in through USB from computer), I will now only use the 302USB to input my mic and send it to the computer. My voice will be added to a virtual input device using BlackHole, as will system audio (e.g. music played on Spotify). I will use this virtual input device to send the audio into Garage Band, where I will be able to apply whatever post processing I want to my mic input separate from the Spotify input. Garage Band will be used to mix the voice and background music, and then send that mix to a virtual output device using BlackHole. That output will be routed to OBS for my live streams. Because I'll be mixing in Garage Band, I will now be connecting my headphones directly to my Mac to monitor GarageBand. So even if it turns out I would get this mystery white noise with the new XLR mic if I monitored through the 302USB I don't have to be concerned with that any longer since I won't be monitoring from there. A quick test with the Sennheiser mic using this routing worked.

Note I know nothing about Garage Band or proper filtering for voice, so that's going to be my next learning moment once the XLR mic arrives. BlackHole for Mac is free (donations accepted). Garage Band comes on the Mac. So this seems to be a no/low-cost solution which not only will solve my mystery white noise issue, but now I'll be able to handle my voice in post separate from the background music. Pretty cool.

 

[Old Music Guy]

Mic Video

I know nothing about lav mics. But I do know something about RF and RF interference. I won't question whether what you are hearing is "white noise" or some other noise source. I would though, point you to this video.
I cannot tell you how many times I have been fooled into looking for noise in a circuit only to find it was computer noise, noise from fluorescent lights, or some other ghost in the machine.
One anecdote: I was troubleshooting a very large Fairchild Component Test system tracking noise. I spent months on this, trying to find microvolts of noise on an ECL logic ground. I finally got hold of a spectrum analyzer, and lo and behold, the noise was emanating from a side band of a radio station that was a few miles away.

 

[macnmotion]

Mic Video

I know nothing about lav mics. But I do know something about RF and RF interference. I won't question whether what you are hearing is "white noise" or some other noise source. I would though, point you to this video.
I cannot tell you how many times I have been fooled into looking for noise in a circuit only to find it was computer noise, noise from fluorescent lights, or some other ghost in the machine.
One anecdote: I was troubleshooting a very large Fairchild Component Test system tracking noise. I spent months on this, trying to find microvolts of noise on an ECL logic ground. I finally got hold of a spectrum analyzer, and lo and behold, the noise was emanating from a side band of a radio station that was a few miles away.

Thanks. I've actually watched that video before, it's full of good information. My issue very well could be from some type of external conflict, but the upshot is that the noise isn't coming in or from the mic, as it doesn't appear in the recording, only in the headphone monitoring. That said, I know almost nothing about audio/frequencies/interference, my MO consists of troubleshooting by altering and changing components to look for patterns.

 

[rob aylestone]

You are going into the wrong socket on the mixer!
The portable receiver is designed to plug into the mic socket on the mixer. That version of the sennheisers, and i have a few of them, has very low output and usually runs with the 3.5mm output connected to an XLR connector. Normally video folk just plug them into their camera audio in instead of a wired mic. It will then be pretty decent snd noise free.

 

[macnmotion]

You are going into the wrong socket on the mixer!
The portable receiver is designed to plug into the mic socket on the mixer. That version of the sennheisers, and i have a few of them, has very low output and usually runs with the 3.5mm output connected to an XLR connector. Normally video folk just plug them into their camera audio in instead of a wired mic. It will then be pretty decent snd noise free.

Ahh, I had no idea. I figured that since people used those two 3.5mm sockets for headset mics, the sennheiser would work the same way. As you said, we originally purchased it years ago and had it plugged into a Canon DSLR, and it's been sitting unused since. Was worth a shot. I didn't realize I could get an adapter from 3.5mm to XLR, but anyway it will be good to have a proper XLR mic in a few days.

 

[rob aylestone]

The Sennheiser cable is a short 3.5mm unbalanced at the receiver end, wired to a 3 Pin XLR, but with pins 1+3 linked for ground with signal on 2. I would not use an adaptor, but either make, or buy the correct cable - the adaptors on the receiver end put lots of stress on the socket. They're on ebay - search for Sennheiser XLR male to 3.5mm like this one UK ebay

 

[macnmotion]

The Sennheiser cable is a short 3.5mm unbalanced at the receiver end, wired to a 3 Pin XLR, but with pins 1+3 linked for ground with signal on 2. I would not use an adaptor, but either make, or buy the correct cable - the adaptors on the receiver end put lots of stress on the socket. They're on ebay - search for Sennheiser XLR male to 3.5mm like this one UK ebay

Again, thanks. I'll find one on Amazon USA and buy it when I visit home in a few months. My Rode XLR mic arrived this afternoon, just waiting for an XLR cable to be delivered tomorrow.

 

[ecc83]

Again, thanks. I'll find one on Amazon USA and buy it when I visit home in a few months. My Rode XLR mic arrived this afternoon, just waiting for an XLR cable to be delivered tomorrow.

I always tell folks to get spares when they buy cables and in your case my friend with high prices and limited availability I strongly urge you to buy a good soldering station and learn to use it. Stuff ALWAYS breaks on a wet Sunday when all the shops are shut!

Dave.

 

[macnmotion]

I always tell folks to get spares when they buy cables and in your case my friend with high prices and limited availability I strongly urge you to buy a good soldering station and learn to use it. Stuff ALWAYS breaks on a wet Sunday when all the shops are shut!

Dave.

All good advice. I think I'll wait until I am in the USA to get spare cables, where I can know I'm getting a decent product -- our online shopping here isn't quite up to par. I do have a soldering station -- but I could definitely use practice

 

[macnmotion]

Here's how my setup has ended up. I think this will work well to learn the ropes for adding audio to my livestream views of the microscope.

 

[Papanate]

Here's how my setup has ended up. I think this will work well to learn the ropes for adding audio to my livestream views of the microscope.

what’s up with the Nikon Optical device?