Samson CO3U microphone advice - noise issue

Mar 07, 2021

Hi there ... I am brand new here and actually came across this site by accident ( super glad I did) because I was following a discussion that Tom wrote way back in 2009.

Anyway, I am recording with a Samson CO3U USB condenser mic and popshield into Audacity on a Macbook. 

I get a really annoying whirring noise which I obviously want to get rid of... I dont know what it is .. the Macbook is as far as I can get it away from the Mic ( without getting longer arms)...but i feel like it must be that.

Any ideas on how I can get rid of this , any experience of this with the Samson? Can I get rid of it in Audacity ?? If so, how.

Thanks so much .. i do t really want to change the microphone but its sounds bad. I've attached a sample.


Thanks in advance for your help

3 Replies
Sally Wiedenbeck

You can definitely try removing background noise in Audacity.

But often the best way to get rid of background noise it to remove it in recording. For that, I would suggest putting something (soft, like a blanket or foam) between your microphone and computer to block the noise. I usually set up my mic inside one of those cloth folding cubes placed on its side. For additional noise reduction, I place a blanket around the cube and over my head. You could also add foam on the inside of the cube instead of using the blanket.

Kristin Hatcher

I agree with Sally's suggestion of making your recording area more insulated. It actually works well to record in a closet or something where there is a lot of fabric around to deaden the sound. If also works pretty well to record in your car (assuming your car is in a quiet place) because your car is built to be relatively sound deadening. 

However, sometimes no matter what steps you take there will be a background hiss or noise of some kind. This is just because the world makes noise, and any good microphone will pick it up. So the next step is editing. 

I use Audacity (a free program) on a Windows machine to edit, so unless you use the same program I can't exactly tell you what to do. However, I have learned a few tricks over the years which may help you. Any good audio editing program will have the same controls I'm talking about. In Audacity, everything I'm talking about can be found in the "Effects menu," and it works well to just accept the default settings. 

1) Noise reduction. Before you do anything else, select a bit of "silence" on your audio clip that doesn't have any talking or whatever, and use it as a sample of the noise you want reduced. Then apply the noise reduction effect. You can do this multiple times. It's better to do it multiple times than to try to adjust the level of noise reduction too much, as that will add some very strange effects to your audio.  I usually do this 2x before anything else. 

2) Apply compression. This tends to bring the levels of all the audio up a little bit, so that will include any background noise.

3) Apply a limiter. This will ensure any louder sounds don't get so loud that they go over the max dB.

4) Normalize. This will even out the loudness a bit.

5) Noise reduction, probably two more times. 

Obviously this is a quick and dirty list, and doesn't truly describe what things like "compression" and "normalization" does to your audio file, but I'm not sure if most people care as long as they are getting a good result. 

Two more effects I didn't talk about is applying a high-pass filter and/or low-pass filter. I find that it's often unnecessary for me to apply those, but they can help a little with things like popped "p's." For popping  and other undesirable mouth sounds, it's best to find the ideal position for your microphone to prevent those, usually above the mouth. 

Depending on how long your audio clip is, what I just described doesn't take very long. I do voice over for my courses, and I can often have clips that are 45 minutes long or more. What I just described would take less than 15 minutes for a clip, often closer to 5 minutes. 

I hope this helps! I went through many years of trying different techniques before I found this process with this software (Audacity).