Hollow noise in recording

Hi all,

I keep experiencing a sort of hollow noise to my narration in audacity. It seems to be present from the initial recording, and can be made more pronounced through certain effects, including equalization. I am trying to figure out the source of this. I currently record in my “home studio”, picture attached. This is in a very small closet with heavy blankets all behind me for sound. (Oh, and I usually have a blanket / towel under the mic stand to account for any noise or vibration.)

I use a Samson Meteor as my mic.

I am attaching two clips for reference. The first is completely raw, the second has mosquito killer applied just for the sake of being able to hear the hollow effect more clearly.

Thank you in advance for the help!!

Screen Shot 2018-10-06 at 1.30.31 PM.png

second has mosquito killer applied

And a good thing, too because you do have some USB mosquito noises in the voice. If you turn the volume up you can hear it in the background.

No, the work doesn’t sound completely natural, but it’s hard to put a finger on it because nobody knows what you normally sound like.

Do you use Skype or other chat app? Make sure those are completely closed when you announce and not just hiding or napping. Did the Meteor come with drivers or other software? The microphone should work without them.

I can detect a little “boxy” sound in there and that could be from opposing walls in the closet.

heavy blankets all behind me for sound.

The rule for trying to suppress boxy sounds is no opposing blank walls. So the little Microphone Cave should take care of microphone rear sound (assuming there’s some soundproofing in the back of the box) and the one behind you should suppress slap from there, but you should put something on either the left or right wall. Out Of Season clothing is not a bad way to do this.

It could still be something electronic. I don’t like that little tick at the 3.2 second mark. It sounds too metallic to be real. Electronic processing can do that.

Are you recording into a laptop? Can you take the microphone and computer outside by themselves and do a 20 second voice test? Stay away from walls, solid surfaces and wind. If all the funny honk clears up, then there’s something wrong with the room. If it doesn’t, then there may be something electronic being done to the sound.

There’s a completely separate test you can do. Crunch up a “real” newspaper during a recording. Newspaper balling has a remarkably clean sound and it analyzes well. If your microphone won’t record that, then we need to find why not.

Scan down a little bit.


Exactly, that’s why I used the mosquito killer for this example.

It’s not a matter for me of sounding the way I do normally, but an author actually rejected my audiobook and complained that it sounded hollow, tinny, and unpleasant to listen to, like I was rec
ording into a glass. She gave me this example of a recording that she says does not sound this way. After listening, I do see what she means, though I think she was exaggerating a bit.

I don’t use other apps that would use a microphone, and no, the meteor didn’t come with drivers or software, nor do I use any.

Is there a way to stop that from happening? What exactly do you mean by electronic processing?

Do you mean I should record a voice test outdoors? Or outside the home studio? It’s currently pouring outside audibly so neither are probably feasible right this second.

Attaching the newspaper test here, the first time with the pop filter, the second without.



What exactly do you mean by electronic processing

That’s rough to describe. If you listen to a news broadcast that they get from somebody on a phone, you hear that honky, whishy background noise and occasionally the voice will go all talking into a wine glass? That’s the cellphone trying to reserve the speaking voice quality in the face of environment noises and interference. High order processing.

There are signatures. The difference between dropping a pencil on a hardwood desk and dropping a fork. The fork gives a little ding sound in addition to the impact. Anyone listening for processing noise will recognize that effect immediately. That’s what that tick at 3.2 seconds sounds like. It’s not likely you dropped a fork, so I can assume you did something natural and sound processing worked on it.

It’s also possible I’m makin’ it all up.

Did you deliver your work to the client in stereo, two blue waves? Most simple voice work is delivered in mono (one blue wave) but there are exceptions. Most of my voice work is delivered to the video people for mixing into stereo shows, so I deliver stereo so to have minimum fuss.

hollow, tinny, and unpleasant to listen to

That’s another signature. That can happen when you connect your broadcast microphone wrong and left-right stereo separation is damaged. It sounds OK if you’re listening in stereo but it sounds like garbage if your sound system mixes down to mono—such as on a cellphone.

You deliver the work to five clients and two of them reject the work as unacceptable trash. The other three are OK with it…??? … Isn’t that fun?

I’m in the field right now so I need to get home to analyze the work. I also need to go back and read how you are recording. It sounded OK to me.


Thanks Koz, I appreciate it when you get a chance!

I record in mono and deliver my work through ACX in mp3s, according the the format ACX requires. I’ve never had an author complain about the quality, but I guess I do hear what she is talking about.


It’s a hollow, tube-like effect, that shows up on the spectrogram as notches …

A possible explanation is acoustic-feedback : sound of your voice leaking out of the headphones getting back to the microphone creating a phasing effect. As you move your head slightly that causes the effect to change , (the notches occur at different frequencies during the recording).

If the hollow effect goes away if you record without headphones plugged-in then you’ve found the culprit.

I > guess > I do hear what she is talking about.

And I think that’s the problem. We’re down on hands and knees in the weeds with a flashlight searching for any little problem that could be fixed. The client is talking about enough serious sound damage that can cause a failure of the contract. Different. She’s not listening to the same thing or the same way that we are. I see no obvious difference (after mastering) between the two clips.

Not every performer/client relationship works out. If we can’t think of a way around this, you might think about throwing in the towel and backing out of the job.

If it’s a completed work, isn’t there provision to submit a partial chapter at the beginning to avoid dances like this? Was there one and was that approved?

Just listening to the little devil on the shoulder for a second, Google the client and client/performer conflicts.


I didn’t think of that - will try in the morning!

Do you hear the tinny effect in my clip? That is, can you hear what she is referring to? Or do you think she is completely nitpicking? Personally, I do hear what she is talking about to a degree. I am almost more concerned at this point about correcting this for the future, so I can deliver the best product to my clients.

…and this is why I’m almost more concerned for future projects. Yes, I had to submit a final chapter, and YES, it was approved and I went on and finished the entire audiobook. Not only did she reject the audiobook for the quality, she also told me the pacing was much too slow. When she said I would have to re-record the entire book if necessary, I politely reminded her of our contract, and how she had already given her full approval of the quality and pacing of the book. That being said, I want my client to of course be as happy with the product as possible. Since I do hear what she is talking about, I’d like to try my best to remedy this for the future, if not possible for this audiobook.

Since I do hear what she is talking about

That’s where we disagree. She’s describing a real, known, obvious-to-everybody problem and I don’t understand how it can be happening. My head is drifting off into monitor, headphone or computer “unicorn” problems because they do happen although super rarely. The show is OK but the headphones or speakers are broken. That’s a no-win because you can’t start instructing the client on the proper use of her computer.

she also told me the pacing was much too slow.

And that’s exactly the point we drift into difficult client territory. Someone else heard the work and hated it, therefore everybody hates it now and we’re nit-picking.

What happened when you Googled the name and a habit of conflicts?


Nothing came up, though I didn’t expect it to since she isn’t super well known. Alright then, I guess I’ll stick to my guns and be adamant about the quality of recording being acceptable. I hate for a client to be unhappy, but you can’t please them all.