High pitch noise in background of my AT2020 Condenser mic

[Jason Skywalker]

I'm not sure yet if this is the result of electrical interference or something, but I've had this issue even before I got my NEEWER 48v Powerbox, Whenever I record anything, I get a high pitch static-like noise in the background, and it always sees to stick there, even when I attempt to reduce it in Audacity. It's not just some little humming, I can deal with that in Audacity if that were the issue.

The issue is that even when I use all these different software people tell me about (OBS Studio, EqualizerAPO, Peace) my voice's volume is always about as loud as this irritating background sound. For example, I've seen tutorials where people say that you need to adjust the gain boost or something, but whenever I turn down the gain, it turns down the mic's audio as well. If I turn UP the gain, the reverse happens, I have yet to actually hear how my mic truly sounds because of this noise, and I desperately need help trying to get rid of it.

I'm not an audio expert, so if there is some kind of Audio-savvy mechanic that's causing this to happen, could someone PLEASE walk me through this step by step to eliminate this issue?

[Wonks]

It sounds like a ground loop noise if it's high pitched.

First things first. Have you tried a different mic lead?

Secondly, how is your recording setup configured. Can you describe what interface and computer and any monitors you've got, and how they are connected and powered? There aren't many audio interfaces without phantom power supplies these days.

[Jason Skywalker]

It sounds like a ground loop noise if it's high pitched.

First things first. Have you tried a different mic lead?

Secondly, how is your recording setup configured. Can you describe what interface and computer and any monitors you've got, and how they are connected and powered? There aren't many audio interfaces without phantom power supplies these days.

I haven't tried a different mic or mic lead because it was hard enough to get the one I have, so I'm trying to work with my XLR one.

I have an HP monitor. I don't have a "setup" because I have to hold my microphone in front of me. What exactly do you mean by my interface? All I have is my power supply and Audacity for Noise Reduction. Are there things I have to unplug? I mean, I do have a lot of devices, such as my Mouse and Keyboard, my Kindle Fire, my wifi D-Link plugged up to the computer, and the multi-adapter plugged up to the wall. I don't know what else to do about these things.

[Sam Spoons]

How do you connect your mic to your computer?

[Jason Skywalker]

How do you connect your mic to your computer?

The input cord is connected to the power supply. The XLR USB is connected directly to the computer.

The multi-power adapter sockets are close to the ground, as they sit on a tray (which is part of the desk) very close to ground level where many things are plugged up into it. Could this be the problem?

[Hugh Robjohns]

How do you connect your mic to your computer?

The input cord is connected to the power supply. The XLR USB is connected directly to the computer.

This isn't making much sense.

If you're talking about the Audio Technica AT2020USB (or USB+) microphone there is no XLR connection, and there's also no power supply as the mic is powered directly over the USB cable.

On the other hand, if you're talking about the original AT2020, it needs a preamp (with phantom power) and an A-D converter -- otherwise known collectively as an 'interface' -- and we need to know what that is. I wonder if this is what you're calling the power supply?

So, more accurate details of the hardware and specific cables will help the remote diagnosis of your problem.

H

[Jason Skywalker]

How do you connect your mic to your computer?

The input cord is connected to the power supply. The XLR USB is connected directly to the computer.

This isn't making much sense.

If you're talking about the Audio Technica AT2020USB (or USB+) microphone there is no XLR connection, and there's also no power supply as the mic is powered directly over the USB cable.

On the other hand, if you're talking about the original AT2020, it needs a preamp (with phantom power) and an A-D converter -- otherwise known collectively as an 'interface' -- and we need to know what that is. I wonder if this is what you're calling the power supply?

So, more accurate details of the hardware and specific cables will help the remote diagnosis of your problem.
H

THIS is the power supply

I don't have an A-D converter. All I have are the parts that came with the Power Supply, the XLR USB cable, and the Audio Technica microphone. The cord that came with the Power Supply plugs into the mic and the USB plugs into the computer. I don't know if there are other pieces of hardware that I NEED, but this is all I have.

[Hugh Robjohns]

THIS is the power supply

Ah. Thanks for that. This is a phantom power supply, so I guess the mic is the original AT2020. The supply appears to have a class II (double-insulated) type, so no risk of a ground-loop via that.

I don't have an A-D converter.

There's got to be one somewhere!

All I have are ... the XLR USB cable

Ah ha! Then this must be serving as your interface / a-d converter! More info please, but I suspect this lies at the route of your problems.

H

[Drew Stephenson]

Ah, so you are taking the output from the power supply straight to the computer using some kind of xlr-usb conversion cable?
That will be where the problem lies if that's the case. The microphone is designed to go through a proper interface, something like this: https://www.dawsons.co.uk/behringer-u-p ... nIQAvD_BwE

[Jason Skywalker]

THIS is the power supply

Ah. Thanks for that. This is a phantom power supply, so I guess the mic is the original AT2020. The supply appears to have a class II (double-insulated) type, so no risk of a ground-loop via that.

I don't have an A-D converter.

There's got to be one somewhere!

All I have are ... the XLR USB cable

Ah ha! Then this must be serving as your interface / a-d converter! More info please, but I suspect this lies at the route of your problems.

H

Sorry, I don't have any more info beyond that. The regular audio jack in the computer doesn't work, so I can't get an interface that plugs up to that. Unless there's an interface that plugs up the USB port? I and NOT that savvy with audio, I really don't get how o why all this stuff works the way it does.

[Jason Skywalker]

Ah, so you are taking the output from the power supply straight to the computer using some kind of xlr-usb conversion cable?
That will be where the problem lies if that's the case. The microphone is designed to go through a proper interface, something like this: https://www.dawsons.co.uk/behringer-u-p ... nIQAvD_BwE

DAMMIT, now I gotta buy ANOTHER piece of hardware?

Isn't there a software that can take care of this nonsense?

Well, can it at least plug up to the USB port? My headphone audio jack is broken.

[Drew Stephenson]

Sorry fella, it's hardware only for this if you want to fix your noise problem. The Behringer I linked to is about as cheap as they come to still give a decent result. You don't need the power supply though, basically your mic connects to the interface with a xlr:xlr cable and then the interface plugs into your laptop with a usb cable.

[Sam Spoons]

Just to complete the circle, what is the exact make/model of the XLR-USB cable you have?

[CS70]

DAMMIT, now I gotta buy ANOTHER piece of hardware?

Isn't there a software that can take care of this nonsense?

Well, can it at least plug up to the USB port? My headphone audio jack is broken.

Look, I understand it's a lot to take in when you start, it was the same for me and for everybody. I did start exactly with an AT2020 - which is a great little mic when used properly.

But you've gotta understand how things work a little, otherwise instead of being fun it's gonna be lots of frustration.

It's not so hard. A microphone produces an analog signal which is carried on the cable. The signal is very feeble, so it need to be pre-amplified to a voltage range which makes it usable to the downstream components. The tool to do that is called pre-amplifier (or preamp). The preamp has usually variable gain (i.e. can amplify more or less) because depending on the sound the reach the mic, you may need more or less of it: for example a drum hit is very loud and will require less pre-amplification than a whispered word.. so if you use the 2020 to record a drum kit, you'll need less gain than if you record, say, your singing voice.

So the first thing after a mic is a usually a preamp. Also, a condenser mic like the 2020 needs some power, which is carried over the same XLR cable that carries the signal but obviously in the opposite direction (to the mic, rather than out of it). This power is called "phantom power" and is normally produced by the preamp. It's just the obvious place where to put it, so most preamps will produce it. In the rare case a pre-amp does not produce phantom power, you'll need a box like yours. The box will give the mic power, while (hopefully) transparently carry the signal from the mic over to its own XLR output, to be connected to the (non-power-providing) preamp.

The pre-amp (with a properly set gain level) will produce an analog signal whose level is strong enough to be processed by the rest of the chain.

So far all the signals are analog (i.e. voltage differentials). When you want a computer to receive the signal (say, to record it on its hard disk), you need something that converts the analog signal into a digital one. "digital" means that it's a stream of ones and zeros. The component that does that is an Analog-to-Digital (A/D) converter. You may also have guessed that in order to drive your loudspeakers (which use an analog signal) with material from your computer (say a YouTube video) you need something that converts back a digital stream (the YouTube stream) into an analog signal: that's a D/A converter.

Every computer with a mic input has already a preamp and a A/D converter (usually not that good) and every computer with a headphone or speaker out has a D/A converter (often not that good either). Conversion happens by looking at the signal many times per second and reporting to the computer the level as observed as number - which is called "sampling". The stream of numbers (numbers can be represented with only zeros and ones) is your digital stream. The quality of the conversion depends on how often you sample, how precise is the "tick" that controls the frequency, how many numbers can be represented by the converter and understood by the computer and so on.

So the recording chain is mic -> preamp -> a/d converter -> computer (insert the power supply before the preamp in case the preamp doesn't produce it already).

However the stock A/D and D/A converters built-in into computers aren't usually that great. To get better results when recording or playing back music, you normally use a dedicated package which contains all the bits of recording and playback chain: one or more preamps (each with its gain control), production of phantom power, good a/d converters, output to USB, d/a converters and two or more line outs (to drive, say, loudspeakers) with the relative volume controls. That package is called an audio interface.

Just for completeness, the individual functional components in any modern audio interface are perfectly good and usable, but it is possible to get even better quality by using separate preamps, and A/D converters - but that's usually higher end kit and with a much higher cumulative costs, for ever less returns. It's also possible to crank all these components directly into the mic and/or a cable. These latter solutions usually are low-end and often not that great. An external USB (or thunderbolt) audio interface is in many ways the best cost/performance compromise.

In your case, it seems that the XLR to USB cable is (or better, contains) the interface.

So the fist question is: is your XLR to USB cable containing a preamp (I guess yes). Does it also provide phantom power? Some do. If it does, by using an additional power source you may be messing up your signal. Do you have control on the gain and a/d conversion parameters? Being a cable without physical control, it may be in software (even if it seems that most don't and have simply fixed gain).

In the eBay ad you link there's no trace of XLR-to-USB cable, only of the usual XLR male-to-XLR female to connect the supply to the mic. Have u purchased the XLR to USB separately?

[James Perrett]

One thought about this XLR to USB cable - is it actually intended for audio or could it be a DMX cable intended to control lighting? The connectors are the same but the function is very different.

[Jason Skywalker]

In the eBay ad you link there's no trace of XLR-to-USB cable, only of the usual XLR male-to-XLR female to connect the supply to the mic. Have u purchased the XLR to USB separately?

Yeah, it was purchased separately from the power supply. This whole thing was haphazard, as I bought the microphone separately from everything else THINKING that the package (from eBay) had everything I needed, only to find out later that it wasn't a USB type, only AFTER I bought the XLR USB cable, only to THEN buy the power supply, only to NOW find out that I didn't need it, and should have just bought an interface. Now I just gotta hope there's a version of the interface you linked to mem available at RadioShack or Guitar Center, cuz I do NOT want to order anything else again.

Thanks everyone for all your help and in-depth explanations on the matter,

[ef37a]

I suspect Jason that you have something like this? https://www.gear4music.com/Recording-an ... gJGuvD_BwE

(eek!) and that I am sure uses the rather poor quality 16 bit converters you find in small, first generation USB mixers. The slightly better news than that above is that you might be able to get passing decent results if you adjust the recording levels in Windows Sounds. Find the device, might be call 'USB CODEC' and find and set the record level. It will normally be at 100% and a boost might also be applied. Turn off any boost then try the level at 20%. You want lusty singing to hit -18dBFS (about 1/2 way up) on the recording software meters, 3/4 max.

But, as everyone has said an interface is really the way to go but try to do a bit better than that 'one lunged' Behringer if you can. If you can find one the Alesis i02 Express is pretty good for $100.

Dave.

[Sam Spoons]

We don't have Radio Shack here in the UK (or GC actually) but they may well have a suitable interface. Guitar Centre certainly will have several and the simplest should not be expensive. Minimum requirement is 24/96 recording (ask them or it will be printed on the box) and a single mic input may be sufficient. GC will probably be happy to help you to get it al working if you buy the AI from them (even though you didn't buy the mic from them, but don't turn up in the middle of a busy Saturday afternoon.......).

Signal chain with that setup :- Mic > XLR-XLR cable > Audio Interface > USB cable > Computer.

Depending what speakers you have the will be better driven from the outputs of the AI.

Good luck.

Great explanation up there CS70 too BTW

[Wonks]

Probably worth getting an audio interface that has full 48v phantom power. Some of the cheapest interfaces only have 15V phantom power, which is enough for some mics (albeit with less headroom) but others need the full 48v (±10%).

The spec requirement for the AT2020 states 48v phantom power, so best not to risk anything else. You could use your existing phantom power supply, but then you need another XLR-XLR cable and it gets messier, so best to get an interface that can supply the full 48v.

[ef37a]

Good point Wonks.
There are one or two cheap mixers that have a low voltage phantom power trap for the unwary.

However, IMHO going for the lowest cost, single mic input AI is very false economy, apart perhaps from the podcaster, anyone with even the slightest interest in music recording will soon feel the lack of "stereo".

Dave.