Hello, I am of course new to this so hello to whomever is reading this.

My recordings pass the ACX check but there is a lot of background noise that does not show up until I “normalize” at the very end. I have no idea how to fix this…

I am using a USB Apex 555 - we switched from an XLR mic (audio technica 2020 with scarlet 2i2) because this has a much nicer sound with my voice…until I normalize.

Just wondering if anyone has any hints.

Thanks in advance.


Record a ten second voice test and post it here.

Click down the blue links—they’re very short.

Is this your first book?

In general, ACX Check is used as the last step before you create the MP3 sound file and publish to ACX. If your performance gets noisy at the end, then it doesn’t pass. Many home performers have trouble passing noise. It’s a pretty stiff requirement.

We publish an audiobook mastering suite of tools and it doesn’t use plain Normalize. Are you using a mastering process from somewhere else? Are you ad libbing?


Is this your first book?

That’s not redundant. We have had posters on their third or fourth book by recording in a hired studio. They appear here when they have trouble recording at home.


A question. How do you know which side of the microphone is the front? Which side to speak into? I downloaded the user manual and they have a paragraph about how important announcing into the front is … and then don’t tell me which side is the front.

That and at least one supplier has the lead graphic on their microphone promotion that I’m pretty sure is the back. There is no detail picture of the front.

As a fuzzy rule, the side you announce into has the company name. Were your instructions any clearer?

You can have some very serious sound problems including noise if you get this wrong.


My recordings pass the ACX check but there is a lot of background noise that does not show up until I “normalize” at the very end.

Normalization is simply an up-or-down volume change and the noise will go up or down along with the signal (the signal-to-noise ratio doesn’t change). i.e. If normalization boosts the volume by +3dB, the peaks, RMS, and noise level all increase by +3dB and just like turning-up the volume control it makes the noise more noticeable.

at the very end.

If you follow the [u]recommended audiobook mastering process[/u], RMS-normalizing is NOT the very-last step. And regular peak normalization is not used at all. The peaks are adjusted/controlled with limiting.

Audacity forum has far snappier response times than other forums. Please post something so we know you’re still breathing.

We can’t easily solve noise problems without hearing them.

We have a terrific track record for getting people published if you work with us.


HI thank you for all your responses to my questions - I am so impressed with this forum. I got caught up in life but i am here and posting my sample shortly.

I use a chain from this forum that my husband got about two years ago- my sample passes ACX checks when I put it through but to me it sounds fuzzy.

Here is my sample as requested - just raw.

Also in answer to some other questions I use RMS normalize and don’t ad lib any steps.

And yes. Today I verified I amspeaking to the right side of the mic, the instructions were clear.

That’s way too quiet.
Try turning up any gain control on the mic and/or
turning up the microphone-level in Windows audio,
see …

Thank you for the test.

Good Night that voice is low volume! That explains why you’re experiencing processing errors.

This is your raw performance on the timeline.

Screen Shot 2019-12-10 at 19.37.38.png
It’s supposed to look more like this when you’re speaking. The blue waves get taller as you get louder.

Screen Shot 2019-12-10 at 19.41.41.png
The bouncing sound meter should reach -10dB to -6dB.

Screen Shot 2019-12-10 at 19.45.13.png

I need to go back and look at the microphone specifications again.


Hello, thank you for your feedback.

I guess my settings may have been changed at some point.

I have put them back to their usual settings and uploaded another sample.

APEX 555 is the MIC ( USB)

BTW pad switch should be on ''0dB''.png

The frequency-analysis on that looks like bass-cut has been applied,
there can be a switch for that on the mic, (similar to the pad switch).

Hi, you are right! I had changed that as I was pulling my hair out trying everything…I have changed it back.

I am not sure what voodoo you have done but it all sounds great now, the constant “chchchchchch” has disappeared.

The biggest change I made was to change what was covering my table - for some reason I had a very fluffy blanket and I covered that with a sheet had I don’t know if I am imagining it but that seems to have made the difference.

I am not sure if you had any other ideas, I am always open to suggestions to make it better,

Thank you so much for your time,

Kindly, Cecilia

that seems to have made the difference.

You can use reflected sound from the desk to make your performance louder, but you do have to pay attention.

If your microphone is on a little stand, it might also change the voice tones making them honkier. This is what we’re trying to get rid of with the blanket or towels.

There is a technique where you lay the microphone right on the desk or panel (example with a smaller microphone).

That can double your voice volume, but then you have to isolate the board from the desk (towel) so you don’t pick up your downstairs neighbor walking around.


Okay I will try that…while the “chchch” has gone there is this weird little “ping”

Is it better to have a “hanging” microphone?

If you’ve not got one already, a pop shield.
It lowers the odds of distortion with plosives like “P”, “B” & “D”.

https ://www.

Thanks, I am using a pop filter but realize I have to learn how to speak correctly to optimize it.

there is this weird little “ping”

Send some of it to the forum. Identify it. “After the words at 3 seconds,” for example. It’s not shocking if your speaker or headphone system is making up its own noises and your voice is actually fine. Are you using wireless earbuds? That’s not the best idea.

I have to learn how to speak correctly to optimize it.

The makers of home microphones would like you to set up in the kitchen, record many successful audiobooks and retire to a picturesque cottage on the French Mal de Mer coast. It’s more involved than that.

Most of your P-Popping and breath noises go straight forward and down, so yes, a hanging or “non-desk” microphone can help.

If you’re using a pop and blast filter (black tennis racket), you should be about a power fist away.

If you have aggressive popping (the tennis racket isn’t perfect) you might try moving the microphone sideways.

If you move it more than about the B position, your voice will start sounding muffled.

Every time you make a change, you should record a test and see where the blue waves settle.

It’s possible you never get the right volume and other corrections may be needed. Home readers never pass noise. I have a really quiet bedroom and I still have to wait for the Metrobus to go by.