New MacAir and Sierra OS - muffled mic

I bought a new MacAir and updated OS to High Sierra. Using Shure mic and Blue Icicle connector to USB. Replaced USB cable, Blue Icicle, updated to latest Audacity 2.2.2. I still need to have my lips on the mic, input level up to max and voice raised to get close to the levels I need. (I do voice over work. All other circumstances are the same. I used to be 6 inches away from mic with recording volume at .79 and the sound was very hot.) Any suggestions?

There’s a gain control knob on the Icicle …

And the gain-slider in Audacity …

If you turn them both up to maximum that’s the loudest you’re gonna get.

(If the mic has a low-cut filter built-in, switching it off will give more output).

[ Some complain the Icicle is not compatible with Shure dynamic mics ].

Okay, just maxed out volume on Blue Icicle (a small adjustment from where it was). Tried to record and got this error: "Error opening sound device. Try changing the audio host, recording device and the project sample rate. The Blue Icicle is the recording device, the project sample rate is 44100. I don’t know how to change the audio host. T

You could do the scratch test. Scratch the Shure microphone and then scratch the MBA’s tiny microphones on the left side. My money’s on you’re recording from the wrong microphone.

Yes, classic Shure microphones have a sound level in the -56dB range and most USB mic preamplifiers only have about a 40dB boost. So you’re left with making up 20dB of volume from somewhere. If this used to work, the most likely candidate is signal routing.

You can check with Audio MIDI Setup.
Go (top of desktop) > Utilities > Audio MIDI Setup. I’m expecting the sliders to be either gray or not be there at all.

Also check Apple (upper left) > System Preferences > Sound > Input. You should be able to select your device and have the sound meter jump when you talk. If so, that’s the device you select in the Audacity microphone window.

Where did this fall apart?


Dueling Posts

Does the Icicle have a light on it? Make sure it’s on and then do that System Preferences thing from the above post.


Yes, blue icicle light is on.
Audio Devices on MIDI output has Blue Icicle selected. Under “master stream” the Master tool bar is grey. Below that, “Front Left” is live. I moved it to the middle.

I have the MIDI “front left” slider up to full. The “Master” slider is greyed out.
Blue Icicle manual knob turned all the way up and Audacity mic input level all the way up. I am just getting to -12 range while being a few inches away from mic. Still not nearly as live as before change to new MacBook Air and High Sierra. Any other suggestions?
I’m under the impression that getting a mic that’s got a straight USB connection (like Blue Yeti) might sacrifice quality. Do you think that’s true or might that help?
(I really appreciate the help!!)

Audacity mic input level all the way up.


You’re not supposed to have a working microphone level control in Audacity with a USB adapter. It’s supposed to be grayed out.

You really really really should do that scratch test. The MBA microphones are those two holes left of the CAPS LOCK key. Start recording and scratch the MBA and then the microphone.

Even if this isn’t the actual problem, you have an unnatural setting somewhere.

Do you have the Icicle mounted stereo? It’s a native mono device and could have volume problems if you cross the settings.


Screen Shot 2018-06-13 at 4.52.56 PM.png
I did the scratch test. Sound is going in through the Shure mic, not the built-in.

When I say mic level, I mean the mic gain-slider. It’s available, not greyed out, and moved up to 1.0.

I’m not sure what possible “unnatural settings” might be effecting things.

I’m attempting to attach a screenshot of the settings above the wave form on an Audacity project I just recorded.

Did you install special, custom driver software with the Icicle?

I can’t think what could be wrong.


Do Not Blow into a Microphone!!

There’s another odd test you can do. Can you make it overload?

Speak louder and louder (yell) with everything turned up full until the Audacity sound meters turn red and the blue sound waves max out their vertical size.

Can you do that, as in, is it possible? Or does the system overload at 50% like this?


Yelling is perfectly valid in front of a microphone.


No. I didn’t need it when I first made the setup (with older Macbook Pro and older OS last summer). Thank you so much for your help! I will post here if I get to the bottom of this issue.

I will post here if I get to the bottom of this issue.

You should do the yelling test. There is a Stereo/Mono volume conversion error that shows up when you do.

I’m not just making that up.