Before I begin narration


I am getting set up to record an audiobook for the first time, with the intent of passing ACX inspection. :astonished:
Using Rode NT-USB and MacBook Air, in the US. When I do the book, my plan is to do the editing myself, but send the mastering to a pro. I hope the offer is still good to give feedback on a 10 second clip! I have prepared one to see if my studio and setup are likely to pass muster before I begin narration. This clip is completely raw.


  1. Any feedback about this clip, and what I might need to change before beginning to record?
  2. When using the plug-in on the forum for checking a clip, is that also supposed to be a raw clip?
  3. Should I also be sending a raw clip to ACX for checking?

Many thanks!!!

Your clip has very high amounts of sub-sonic noise. Fortunately that is very easy to cure, with the “LF Rolloff for Speech” equalization curve. After applying that your noise floor is in great shape.

Beyond that you need a bit of compression to get the required RMS-peak ratio. If you search the forum you’ll find lots of compressor recommendations.

Tell us a bit more about your home studio… Custom built room? Old closet lined with egg cartons? Whatever it is it sounds excellent.

Thank you so much, flynwill!

I think I see evidence of that noise, but I cannot figure out where it comes from since I can’t hear it. It is a great relief to know more about it and especially that it can be removed.

My “studio” arrangement needs to be flexible, and I’m not planning on making this a business, just recording a book as a favor for a friend, and maybe a couple more for other friends if this works out OK. SO - the studio setup is a corner of my bedroom, with the (too small for walk in) closet door open to take advantage of the clothes behind me, a large 4-panel oriental screen draped with a quilt blanket in front and one side, and the microphone half-way into a cardboard box lined with acoustic foam protecting the other side. I put a big wool carpet on the (wood) floor, closed all of the drapes and put a blanket on the table. All in a very quiet neighborhood, thank goodness.


The noise is electronic in origin, probably from the pre-amps inside the microphone itself. The good news is there is no trace of the “yeti curse” the high-pitched whine that infects a lot of USB microphones nor is there any hum from the power lines, the other common problem.

If you’re that far along, you may be able to do the mastering yourself. Many people do.

Flynwill wrote ACX Check using a collection of existing tools. It will tell you whether you’re likely to meet ACX technical requirements.

You’re head and shoulders over the people who read the entire book and depend on painful post production processing to “rescue it” if it fails. A rumble filter is included in the suite.

The ACX requirements are not magic. They’re perfectly normal sound requirements and any radio or TV station can meet them. Anybody with a quiet room and reasonable microphone can meet them. You don’t even need a microphone. I did it last week with a stand-alone pocket personal recorder in my quiet third bedroom and I know people who read books with very little more than that.

What you can’t do is plop a USB microphone on the dining room table in the average noisy apartment and crank out audiobooks. This is what the USB microphone makers keep insisting you do. The longest post in the history of the forum was Ian who just wanted to do voice work from his Hollywood apartment. His noisy Hollywood apartment.


I pushed the clip through the mastering suite.
Screen Shot 2018-06-07 at 07.22.47.png

So we’re done. I’m going to breakfast.


Oh. One more. I don’t know if ACX has provision to submit a test. Their requirements change a bit over time. If you find out, please post back.


just recording a book as a favor for a friend, and maybe a couple more for other friends if this works out OK.

You sailed past the ACX technical requirements and you have a very pleasant presenting voice. You are the poster child for doing this as a real job.


I cannot thank you both enough - for the specific help to me, creation of the ACX check program, your kind words, and for all of the posts helping others that I have been reading for the past couple of weeks. I picked up a lot of great info here, and saw clearly the advantage of making every attempt to “fix in pre” rather than “fix in post”.

Also, I am very glad that the sub-acoustic noise is not my home’s wiring. It was amazing to read in some other post that you can figure out the country based on the hum. I had nightmares of trying to record in the dark…

Now waiting for the garbage trucks to finish their rounds so I can start recording. I’ll see if I can use the tools you suggested to try mastering and testing a whole chapter.

Thanks again

you can figure out the country based on the hum.

More like the continent rather than the country. There’s only two major ones, so basically, we can tell if you’re in the US or not.

I had nightmares of trying to record in the dark…

Candles don’t make noise. Tungsten Incandescent (regular light bulbs) are silent until you dim them.

The newer LED lamps make no noise.

Fluorescent lamps and CFLs can make noise. Dimmed incandescent lamps make noise. I have a CFL desk lamp used as an effect and not for useful lighting. It buzzes. Any minute now I’m going to change it out.

I can use the tools you suggested to try mastering and testing a whole chapter.

Mastering Suite 4 is a Suite. Harmonious Collection. Use the tools beginning to end. It’s designed to work on raw readings. We can’t take effects out of a show, so once you do something messy, that’s the end.

Also any minute now, I’m going to write up “Recommended Practices.”

When you get to the end of a reading, Export the work as WAV (Microsoft) 16-bit and copy it somewhere safe. External drive, thumb drive or cloud. Lots of options.

Do production on a copy. There’s no such thing as “the dog ate my computer and I need to read it again.” Just open up the copy and use that.

Do not use MP3 for anything until you get to the ACX submission. They require it. Did you install the Lame software? Audacity won’t make an MP3 without it.


Rode NT-USB and MacBook Air

MBAs do have a fan. I thought for a long time my Air didn’t and then one day I overloaded FireFox. More open tabs than one person aught to have.

The machine started to get warm and the tiny fan went on. …eeeeeEEEEEEE.

I would not be good for that to happen in the middle of a paid reading, so it’s recommended to close all other applications and disconnect the network and/or shut down the WiFi when you read.

If you’ve been reading the forum posts, you know stuttering, crackling and popping readings are common with live readings. Unless proven wrong, those errors are caused by the computer doing something else while it’s recording the work.

Live readings don’t wait. There’s no such thing as “Hold on a minute while I process this spreadsheet or update Skype.” Each word follows the next and the computer has to be there for all of them.

Clean slate is good.


Thanks again.

If my wiring had caused a noise, I suppose the candles could work as an alternate light source, though a potential fire hazard. :laughing:

The additional tips are appreciated. I have been turning off wi-fi while recording, and I am watching for the fan noise in the MacBook Air - happily it is rare, as Koz said. I will follow the mastering suite steps on a fresh copy.

I did find info on how to submit a test to ACX, and I followed their steps and got a nice automated email back saying that I would have results in 5-10 days. I will post in a new thread about the whole process once I see what they send me.