Tinny sounding dynamic mic

Hi Audacity community,

I’m new to podcasting and to audacity. Recorded my second interview yesterday. It was in a hotel lobby so instead of using my better condenser mics I used a pair of backup Audio Technica MB3K hypercardioid dynamic vocal mics. They were effective in not picking up most of the background lobby noise, but when I play back the raw recording, our voices have a tinny, magnetic quality. It’s hard to describe, and it’s subtle, but I can definitely hear it.

Here is a link to an mp3 section of the recording: https://politypartners.files.wordpress.com/2017/03/dynamic-mic-selection.mp3. Aside from importing the WAV file to AUD and then exporting to MP3 so I could post a link here, I haven’t edited the audio at all,

I would love any advice about using EQ or some other effect to help get rid of that subtle tinny, magnetic sound.

Many thanks,

OK, so we have a field interview recording. How did you record it? On what? Model numbers?

Two microphones? Are they each on their own tracks, say Stereo Left has Microphone One, Stereo Right has Microphone Two?

It will take a minute to pull down the track for listening.


Koz, thanks for the quick response. I used two mics, each on their own mono track. (The MP3 is just one of the tracks, not both). Recorded it on a Zoom H6 then just transferred the WAV file to audacity on my laptop.

Screen Shot 2017-03-17 at 18.55.14.png
I don’t think these are what you think they are—unless I got the wrong one.
Have you used these microphones before?

It’s never a good sign when the ad says " High Output" and “Extended Response for Clarity.”

That usually means overly crisp and sometimes harsh with higher distortion than you would think.

It’s not hypercardioid. It’s “unidirectional” which means most of the sound comes in from the front most of the time, but don’t hold us to that. Real hypercardioid looks like reverse garden hose water. Unless you’re right in front of it, zippo, nothing.

I think it’s doing the best it can and if you didn’t compare it to anything else, would work OK. There is a sibilance filter (SS SSS SSS) that I tried quickly, but I must have adjusted it wrong because it garbled the voice. It’s a bit experimental.

I’ll see if I can figure out who supplies the filter.

The voice clip has a 100Hz cut-off (rumble) filter applied. That’s what I’d be doing with a field recording, but it can make male voices slightly gutless, particularly if they have a lot of gut (announcing voice). You can’t bring that back without bringing up the room rumble.


Have you learned your lesson about how darn much fun it is to record in the field?

As we go.


See if that’s any better. Everything from “Scotsman” forward has a little anti-crisper applied. I can forward the custom curve I used to get that.

This is where we ask you how are you listening? I have a silly joke where if you can hold your speakers in one hand, you should probably get something else. Hollywood uses a particular Sony headphone for field use.


I don’t know that I would be listening to my Moody Blues collection on these, but if something goes wrong in a field shoot, I’m going to hear it before anybody else catches it.


There’s sizzly interference on “very first windmill” I don’t think anything can be done about that.
DeClicking & DeEssing generally improves matters IMO.

Free DeClicker & DeEsser plugins for Audacity are here.

That’s the correction suite I was looking for.

There’s something wrong. Are you sure we got the right microphone? I found several listings for the Audio Technica MB3K and it’s like they’re describing different microphones. That and I can’t find a factory data sheet.

To put this in perspective. I know people who have pulled off very difficult voice sound shoots with one of these.


Something like that is what’s likely to be inside this wind screen.

Ira Glass and his show This American Life was one of the first people to discover you could use a long-distance, shotgun microphone in hand-held configuration for an interview like that. It’s possible to do that interview using older techniques, but it’s more expensive, much more complicated, and for only marginal improvement in vocal quality. The shotgun technique took over because of its obvious simplicity and ability to deliver near-studio interviews in difficult conditions.


These people have some good ideas about voice recording.



Koz and Trebor, thank you both for your responses.

You’re right that the mic is a discontinued model. It also makes sense that it’'s unidirectional and not hypercardioid.

Here is the recording setup I used:

The condenser mic in the middle was just a backup; I am only using the two dynamic mics on the final edit. The Ira Glass shotgun method looks great but maybe more for a “man on the street” type of interview. For my limited budget I am trying to find a way to make my existing mics work the best they can.

The headphones I use are basic Tascam TH-02. The Sony pair looks great but I need to wait a bit to invest in those.

Koz, yes I am interested in the curve you used on your edit. My email is jcohen at politypartners dot com or you can message me on this forum.

Trebor thanks also for the link to those plugins.

Thanks again to both of you!


OK, well, if somebody had a gun and said I had to use your microphones…

I’d throw the mic stands away. The more backtime you have, the fancier you can make this.

I’d put a foot-square piece of plywood on a towel and put the microphone on that. This is just what I had in the garage.
With more backtime, I would drill about a one-inch, shallow hole in the middle of the board so I don’t need the tape to keep the microphone from rolling away. Paint the board flat black and use Duvetyne instead of a towel.

This is the technique used with a simple lavalier microphone.

Duvetyne is Hollywood-speak for heavy flannel/felt, almost always dead black.

Why on earth would I do that? That’s “fake” pressure zone configuration. It almost doesn’t affect the quality of the microphone, but it doubles the volume of the voice. Not kidding. 6dB free volume boost. The towel isolates the microphone from desk, table and floor noises (unlike your stiff stands). Pressure Zone isn’t subject to desk surface slap echoes and comb filtering effects (talking into a wine glass). Yes, you can get rid of those last two with a heavy towel or blanket on the desk, but this is easier.

If nobody had a gun and didn’t care which microphone I used, I’d be using lavaliers.

I need to dig for that equalization filter…wrong machine.


DO NOT stop using a backup microphone.

This is the custom curve, DeCrisper3.XML. Your microphone has a boost at certain tones that are rough on the ear. This helps to suppress those tones. It just takes a little edge off the voice.

Adding Custom Audacity Equalization Curves (LF-rolloff as an example)
– Select something on a timeline.
– Effect > Equalization > Save/Manage Curves > Import
– Select LF_rolloff_for_speech.xml > OK. (it won’t open a ZIP. You have to decompress it)
– LF rolloff for speech now appears in the equalization preset curve list.

I expect the lower-right of the equalization display to look something like this. I don’t think I can easily get the whole display on the forum.
Screen Shot 2017-03-18 at 12.02.33.png
DeCrisper3.XML (292 Bytes)

Thanks Koz this is great.

Why lavs over a standard handheld dynamic mic? (The more you write, the more questions I have!)


If the environment is noisy, I would be cycling through the bag trying to find the best microphone for the job.

A difficult environment restricts your options and usually increases the price and risk. See: the reason you’re here.

If it’s difficult enough, you leave standard microphones in the dust and pull out the dusty tricks.

There is a technique where you use two identical hand-held microphones and a special “Y” cable to get them into one XLR-Male for the recorder. The two microphones are wired out of phase—backwards—and you use them taped to each other with the heads together. If you did it right, they won’t pick up any background noise at all and you use the microphone system by close-talking directly across one of the two heads. It’s not HiFi, but it will get you a working track in high traffic or a noisy factory.

One of the rules is to get the microphone as close as possible to the voice. You may find that a correctly placed lavalier at 6-7 inches below the mouth will pick up a lot less room trash with a better quality voice than trying to struggle with a noise-cancelling microphone on a table five feet away.

Or not. There’s no good way to predict what a difficult shoot is going to need. That’s what makes it so darn much fun.

The lavalier in the pictures is the Radio Shack 3013, on the market for centuries.


It’s a copy of an Audio Technica model. AT may have made it. Two problems. You need a non-standard adapter to get it plugged into an XLR and it’s not particularly crisp. So it would have the opposite problem of your microphone. Slightly dull. It used to come with a tiny wind screen which worked really well for wind, but made the voice even more muffled. Anybody trying to boost crispness is going to run into microphone amplifier noise. Ffffffffffff.

Right about now, you decide the best way to get the performer into your studio.


Koz, thanks again for all your feedback. I didn’t set up the wooden board like you did in your photo, but I did run out today to the fabric store (maybe the second time in my life I’d been there) and bought some felt padding sheets to use under the desktop mic stands.

Thanks again for your prompt responses. It is a big help.


You may need several layers of felt to do any good. Duvetyne is superheavy black toweling (dual-velvet) and I’m not sure anybody could shoot movies without it. A good sub is furniture moving pads. Ignore the microphone and book. That’s what’s covering the table.

Also see this broadcast shoot. Forget the microphones and look at the table.

What you don’t see in that last picture is the soundproofed conference room we’re recording in. I treat the office managers very well (Are you comfortable? Can I get you some coffee?) so I can get that room any time I have a sound shoot.