How To Meet ACX Requirements Using Audacity

[@alexandercaskey9243]

This video is an example of what all instructional videos should aspire to. Perfect pacing, clear exposition, and summary'review. Strong work!

[@HomebrewAudioRecording]

Thanks so much, Alexander. So glad it was helpful!

[@jowoodman9665]

Agree, excellent video. My only thought is there's not an addressing of the noise floor being too high - though that's likely due to an improper and noisy audio setup, so it's probably not going to be fixed post-recording, anyway.

[@HomebrewAudioRecording]

@@jowoodman9665 I always run light noise reduction on the entire file (after making sure to record in a quiet space) in order to keep the noise floor under max. That always works.

[@cdivaris]

Thank you, thank you, thank you! I nearly ripped my hair out during my first ACX book because I could not figure out how to do this simply. You are the best!

[@HomebrewAudioRecording]

Awesome! So glad it helped!

[@thecandibyrne]

Thanks for the clear, succinct instructions. Just the juicy bite I needed to get me into the closet to record my audiobook!

[@HomebrewAudioRecording]

You're welcome! So glad it inspired you get recording 🙂.

[@thekarmafarmer608]

I thought my first audition piece was great until I ACX checked it. This video saved my stress levels for the day. Thank you for making these videos.

[@HomebrewAudioRecording]

So glad it helped! I like to know I could lower the net stress level in the world from time to time 🙂

[@8stringwrshpleader]

Dude, you literally just made this whole thing make sense to me! I have literally spent HOURS modifying the levels and normalizing and tweaking to get a long good take to work! This is such a HUGE help! Thanks for the concise and direct explanation!

[@HomebrewAudioRecording]

Excellent! So glad it helped. Yeah, this audio stuff is often made way more complicated than it actually is. I see it as my mission to help fix that 🙂

[@uryic000]

Thank you Sir, I am a full time musician, arranger, composer and educator. Recently one of my former students who is now an adult published her 1st book. She plans to convert it to an audio book and asked me if I could do the recording for her. My expertise is in playing piano/keyboards, arranging, mixing etc. Though I have the tools to do mastering, I had not invested a lot of time in it. Mainly I spend my time composing arranging, etc. It took me 5 hours of reading and trial and error working in Ozone 8 mastering software before I stumbled upon your EXCELLENT video. Straightforward, to the point, and EASY to understand though the Audacity download and ACX test software was a little different than what you mentioned on the video. But it still was extremely intuitive and easy to do. I have around 17 tracks to prepare for ACX and it WAS going super slowly and tedious. But now after your video I'll finish in couple of hours tops. Thanks again. New subscriber, and triple thumbs up wouldn't be enough to show my gratitude.

[@HomebrewAudioRecording]

Glad it was helpful, Gregory! Thanks for the kind words.

[@kimmielove3384]

Thank you so much! You have no idea how much this helped. YOU ARE A LIFESAVER! WOW-I finally got all three to pass! You rock!

[@HomebrewAudioRecording]

Awesome! So glad it helped.

[@HungerDame]

THANK YOU for creating this video! I am just starting out with ACX/Audacity, and I got more out of these instructions than any other tutorial I've seen this far. I greatly appreciate your work.

[@HomebrewAudioRecording]

You're welcome! So glad it helped. And thanks for your kind words!

[@salbahejim]

DUDE! I've recorded several clips and fail to meet ACX requirements every time! When I amplified to peak of -3dB I pass everything but the RMS is always too low. This solved that!! Thank you so much!!!

[@HomebrewAudioRecording]

Awesome!! So glad it helped!

[@markiedoczi1987]

Thank you! This video helped me correct my 15 minute checkpoint for my 1st gig, and I will be saving it to refer to later. Thanks again!

[@HomebrewAudioRecording]

You're welcome! So glad it helped you!

[@ChubbyAmadeusFan]

Thanks so much for a great tutorial! Clear and concise instructions.

[@HomebrewAudioRecording]

You're welcome!

[@browndamon]

Fantastic. Thanks, Home Brew 👏🏾

[@HomebrewAudioRecording]

You're welcome!

[@tolitosjones3431]

Very helpful! Any tips to pass noise floor?

[@HomebrewAudioRecording]

Running a noise reduction effect on the whole track usually does the trick. Just make sure it doesn't mess up your audio (sometimes leaves an artifact behind making the audio sound "swirly."

[@MarsX3DTHEEVIDENCE]

This is invaluable information! Thank you so much for sharing your knowledge with us!

[@HomebrewAudioRecording]

You're welcome! So glad you find it useful!

[@UnionOrganizerShorts]

You just saved me a ton of cash. Thank you! 3 minutes in, problem solved.

[@HomebrewAudioRecording]

That's awesome! so glad to hear it was helpful.

[@BlueBeastFilms]

Perfect. Helped me figure this out. Thank you!

[@HomebrewAudioRecording]

You're welcome! Glad it helped.

[@cheynestilwell2013]

This is EXACTLY what I needed! Thanks for posting this video!

[@HomebrewAudioRecording]

Awesome! So glad it helped you!

[@LizLeafloor]

Wow - thank you very much. I'm new to this, and this was a great walkthrough.

[@HomebrewAudioRecording]

You're welcome. And thanks for the kind words!

[@JohnSan92]

Super helpful! Definitely came in clutch as I need to record an audiobook in 3 days

[@HomebrewAudioRecording]

So glad it helped!

[@kitetales]

Thank you so much for this, it's such a wonderful tutorial!

[@HomebrewAudioRecording]

Thanks so much! I'm glad you liked it and hopefully found it helpful for you.

[@Sethduloongo]

I really appreciate all that you do on this channel!

[@HomebrewAudioRecording]

Thanks!

[@reprogrammingmind]

why is the audacity file only taking up the top 12% of your screen....show us!!!

[@cryptoboy1091]

thanks a lot . one question. so, the steps are > narrate audio> run acx check at audacity> edit according to requirements> check again> if ok publish. right ?

[@HomebrewAudioRecording]

That is correct.

[@ApeIronProduction]

Thank you! This was exactly the help I needed.

[@HomebrewAudioRecording]

You're welcome! Glad to hear it!

[@shevoncruz-carrion3204]

This was a very informative video but still did not complete the check due to the noise floor being too high. I have no idea on how to fix the noise floor.

[@HomebrewAudioRecording]

Noise floor is simply a matter of using the Noise Reduction tool. I've never had that not work. Did you try that?

[@alexandertye3244]

Is the course contains the same type of videos as these? And how much hours is the course?

[@CANTORANDTHEWORD]

This was so helpful. Thank you so much

[@HomebrewAudioRecording]

You're welcome!

[@meganhall7096]

Nope. Still failed on the noise level floor. No idea how to fix this.

[@HomebrewAudioRecording]

Try running a noise reduction on it also. That'll take care of that. And if you ran it to -18 RMS, that shouldn't result in too much avg loudness reduction.

[@PatrickCainam]

I, too, failed the noise floor while passing the Peak Level and RMS Level. Following your tip, ran Noise Reduction, and now my Noise Floor is too noisy, and my RMS is too quiet. I’m thoroughly confused. Any advice?

[@HomebrewAudioRecording]

@@PatrickCainam If you ran a noise reduction, it doesn't make any sense at all that you wouldn't pass the noise floor check. If it were me, I'd start over on the original audio (hopefully you kept that and saved each edited version with a different file name) and START by running noise reduction. then run the ACX check. If the NR was done properly, there is no way you should fail the noise floor part of the check at this point. THEN you can work on the RMS peak and avg pieces. Hope that helps.

[@MommyAnswerLady]

What if there are silent spots in the audio so it shows a warning about that? Will that pass too?

[@HomebrewAudioRecording]

It shouldn't. Are you getting a warning from ACX check? If so, what does it say?

[@MommyAnswerLady]

@@HomebrewAudioRecording I figured it out sort of. The acx check In Audacity says PASS on both necessary things, but then has a warning that silent spaces don’t sound natural. I haven’t gotten to the point of trying to load it to acx yet. Still working on that.

[@HomebrewAudioRecording]

@@MommyAnswerLady That whole "silent spaces don't sound natural" thing is very subjective. And I don't agree. It isn't true across the board. Sure, if there is audible room sound mixed in with your voice, and then the gaps between phrases are missing that room sound, then sure. It might sound a bit jarring/unnatural. But I don't think there SHOULD be audible room sound. If you have a quiet enough space, there won't be any audible room sound/noise during the times when you are speaking. So moving from that to total silence won't be jarring at all. I think this is just the automated system making assumptions. And when it encounters absolute silence in those gaps, that message triggers.

[@MommyAnswerLady]

@@HomebrewAudioRecording Thank you! ALL SOLVED! I appreciate that so much.

[@HomebrewAudioRecording]

@@MommyAnswerLady Awesome!

[@andresbarcelo]

This fixed everything but my noise floor still too high

[@MommyAnswerLady]

I have all my audiobook files done, have loaded them onto ACX and FindVoices so it will be available for sale there. BUT, I want to also offer my audiobook for download purchase on my website. Is there any way to convert mulitple mp3 files to an m4b file so I can sell it that way? I cannot for the life of me figure out how to do that on a PC. Can you help?

[@HomebrewAudioRecording]

That is something I don't know, I'm afraid.

[@MommyAnswerLady]

@@HomebrewAudioRecording I thought this would be something very simple. Audiobooks being so prevalent and growing you'd think that would be a big market to teach this! It seems anyone who is teaching is only doing so to go on the big platforms and not to sell your own audiobook yourself. Hmmmm.....thank you anyway.

[@Bangledorf]

Thank you for posting this video. It was exactly what I have been looking for!

[@HomebrewAudioRecording]

Awesome! So glad it helped :-).

[@winnieumbrellabrand]

Thank you. You explained everything so well.

[@HomebrewAudioRecording]

You're welcome! So glad it helped.

[@thetributary8089]

Insanely helpful, thank! Now to solve my noise floor issue. :/

[@HomebrewAudioRecording]

You're welcome! For noise floor, try using the Noise Reduction effect.

[@matthewj.evans-author]

That was very helpful. Thank you.

[@HomebrewAudioRecording]

You're welcome!

[@OverdriveDiecast]

The video is a little bit to outdated to do this with .You have done a great job explaining, it just doesn’t really have the same layout anymore in spots.

[@OverdriveDiecast]

The limiter is not even the same HUD so I’m not sure where to tweak that .

[@HomebrewAudioRecording]

@@OverdriveDiecast Ooo, thanks for letting me know that! I have updated that in the comments section, which will help until I make a new version of this video. Here is the info: [UPDATE 2025] There a few changes in the limiter controls for Version 3.7. "Soft Limit" is the default now, so no need to select it. And "Limit To" changed to "Threshold." And since we do not want any makeup gain (like it says in the video), set the "Make-up Target" to -3, the same as the Threshold.]

[@OverdriveDiecast]

@@HomebrewAudioRecording Your the best thanks man . I hate text , reading it back it sounded rude but I was just mid thought trying to figure stuff. Thank you for responding 🫡

[@HomebrewAudioRecording]

@@OverdriveDiecast You're welcome! 🙂

[@OverdriveDiecast]

@ Hey , so everything is passing except the peak level is to high apparently -2.43 still . Any tips for this ?

[@sherifwahba4653]

Thank you very much for this tutorial! I use REAPER to narrate, How about if I want to upload an audiobook on KZbin? What requirements do I need?

[@HomebrewAudioRecording]

There is no strict requirement for that. Not like ACX where they will not even accept the audio if it doesn't meet the requirements. KZbin will turn loud audio down to their target of -13 LUFS (NOT RMS). But they won't turn audio UP to that level if it isn't loud enough. But they won't refuse to let you upload the video. Hope that helps.

[@LifeCoachMentoria]

thank u so much!

[@HomebrewAudioRecording]

You're welcome!

[@angietripp9447]

Hi! So I walked through all the steps in my lap top to download the acx check it said installed successfully but when I go to my analyze list it doesn’t show up. I tried add/remove plug in to be sure it was enabled and it was. Any advice would be GREATLY appreciated!!

[@HomebrewAudioRecording]

You seem to have done the right thing - checking Add/Remove programs to see if it was enabled. I don't have an answer, unfortunately. My recommendation is to check the Audacity forum here: forum.audacityteam.org/

[@monicacriswell806]

Audacity Wiki page has been archived. Do you have any recommendations on where to find the ACX check download & instructions now? Thanks!

[@HomebrewAudioRecording]

Just checked and it's here: plugins.audacityteam.org/analyzers/analysis-plugins#acx-check

[@aminnellis]

What about the noise floor? Just took some audio like you did and did normalization, then limiter, and it wasn't quite there so I did normalization AGAIN then limiter again to get the peak level and RMS level to pass but now the noise floor is a -38 db fail

[@HomebrewAudioRecording]

Did you try using noise reduction?

[@aminnellis]

@@HomebrewAudioRecording it's just too loud where I am I'm never going to be able to do something like this. Wish I could live alone but I'm never gonna be able to do anything

[@reprogrammingmind]

@@aminnellis never? get a grip

[@aminnellis]

@@reprogrammingmind lmao you have no fucking idea dude

[@kaylapolanco4463]

My limiter menu looks different from yours. Is it because I have the free version?

[@HomebrewAudioRecording]

It's because they changed it in one of the recent versions. Sigh. I put how to set the new version limiter in the description. It says: "[UPDATE 2025] There a few changes in the limiter controls for Version 3.7. "Soft Limit" is the default now, so no need to select it. And "Limit To" changed to "Threshold." And since we do not want any makeup gain (like it says in the video), set the "Make-up Target" to -3, the same as the Threshold.]" Hope that helps!

[@mooseydeucy]

Great tutorial. However, I recently have the OPPOSITE problem: The ACX check says my read is "too low, -8.20db may be too quiet" . Its a solid read, I have a baritone voice and did not whisper! What gives? basically but my noise floor "too low dead silence sounds unnatural" wtf? Silence is "golden" right? Why do they make this such a nightmare? How to fix THAT scenario, please? SMH

[@HomebrewAudioRecording]

You just need to get the average loudness (RMS) to be between -23dB -18 dB. So it sounds like yours is less than -23dB. Have you tried to use the "amplify" effect to turn that up? Also, what is it saying about your noise floor? I've never seen it say it was too quiet. It could possibly be there isn't "0.5 to 1 seconds of room tone at it's beginning and 1 to 5 seconds of room tone at its end." I agree with you about "room tone." Some think it is important, but unless it sounds unnatural, I usually just use noise reduction to get it virtually silent. And then to meet the "0.5 to 1 seconds of room tone at its beginning and 1 to 5 seconds of room tone at its end" requirement, I just copy some of that silent space to create that amount at the beginning and end.

[@mooseydeucy]

@@HomebrewAudioRecording Thanks but I feel like hiring someone to do all of this nitpicking because it has taken almost one year to record and upload with acceptance by the almighty ACX, all of these chapters of this poor author's audio book version. He chose me for my voice. I had NO idea that submitting these would cause such a fuss. I have over 40 years in music radio up to 2013 when I had to return home to help my mother in her final years, and this makes me yearn for the good ole days of reel-to-reel tape and razor blade editing. Gee WIZ. SMH

[@HomebrewAudioRecording]

@@mooseydeucy It certainly is valid to hire someone at some point when it is wasting too much of your time.

[@mooseydeucy]

@@HomebrewAudioRecording Hi and thanks for your support. Sorry for sounding negative within my frustrations. 'Just got nerve up to try to set the levels between minus 23 and minus 18 to no avail. It doesn't let me do it! I have a screen shot, if anybody can help? Only two chapter files left for this very patient author. I go to "effect", "volume and compression" and then "amplify", but the box doesn't give opportunity to apply these values? Am I doomed?

[@HomebrewAudioRecording]

@@mooseydeucy You are not doomed. I do offer coaching calls if you want to set something up to walk through it. I think I can help. If you'd like to do that, contact me here: www.homebrewaudio.com/legal/contact/

[@gaelicpros]

ooops..... that plug-in page link has an ny extension that will NOT download to my Windows 10.

[@HomebrewAudioRecording]

That's odd. I did this video on a Windows 10 computer. Did you go here: wiki.audacityteam.org/wiki/Nyquist_Analyze_Plug-ins#ACX_Check ?

[@nettiegurl]

@@HomebrewAudioRecording It just keeps downloading as a blank page ext. that won't open, and redirects to MS office store :/

[@HomebrewAudioRecording]

@@nettiegurl Wow, that is strange. I have not heard of that. I can only recommend asking on the Audacity forum here: forum.audacityteam.org/

[@reprogrammingmind]

@@HomebrewAudioRecording THIS IS THE UrL ThE OtHeR COmMEnTER SpOKe OF

[@HomebrewAudioRecording]

@@reprogrammingmind I didn't see a URL in your comment. The forum one I put in my comment above is working right now. So I assume you didn't mean that one. Did you mean to send one?

[@jamescampanella3421]

I understand that this method is what you need to do to get a sound file accepted on ACX, but I am not thrilled with the results. My files were edited beautifully-- I even removed most of the obvious breaths during narration. They sounded great until I applied the sound normalization algorithm. All the breaths that you could barely hear and the minor background sounds suddenly became amplified as the normalization didn't just normalize the actual narration but every barely audible background sound as well. In addition to that the whole thing sounded way more "hollow" after normalization. My files passed for ACX acceptance, but they sound like crud compared to what they were before messing with them. Any suggestions on how to fix this problem? It seems to me that I would have been better off editing the files *after* normalization and not before, which is a great lesson to learn for the future, but it does nothing to help the files I am working on now...

[@HomebrewAudioRecording]

Yes. You've discovered what can happen when there is too much compression, followed by makeup gain (squashes the audio down to make it more even in volume, and then turns it up to the target loudness level). You're describing a pretty common artifact of that. And one of the ways that loudness normalization achieves its goal is to apply that compression-followed by auto-makeup-gain. So the more changes that need to be made to your audio, the worse those side effects will be. What you can do to minimize this is to try to even out the levels of your audio more gently, and apply your own adjustments in level until it is as close as possible to the ACX goal. So maybe some gentle compression first to even things out. Then use standard normalization (peak normalization) to increase the overall average level. Peak normalization does NOT apply a compressor. It simply increases (or decreases) everything until the loudest peak reaches the target you input. THEN listen again to the breaths and stuff in between phrases and noise. You might want to use a breath control plugin like in RX, and apply a bit more noise reduction at this point. THEN you apply the Loudness normalization. Basically you do as much as you can control to get the average loudness as close as possible BEFORE applying the automatic Loudness Normalization (LN), so it doesn't have to do as much work. So the further away you are from the targets - especially average loudness, prior to using LN, the more work it will have to do and the worse the side effects will be. So the less it has to do, the less you will hear these problems. I hope that helps.

[@spookynightthelegendofclar4049]

I am so GLAD I am here

[@bright_bright_heart]

Thanks a lot !!!!

[@KenTheriot]

You're welcome!

[@spookynightthelegendofclar4049]

Excuse me but I have Audacity 2.2 What Version is recommended for ACX check? Because seems like I have a problem downloading it

[@meganhall7096]

I recommend you update to 3.1.3

[@HomebrewAudioRecording]

Definitely get the latest version of Audacity, which is v 3.1.3. No reason not to, since it's free.

[@EpicPlayzee]

Now export and then check it agian ACX then you fimnd same acx failed

[@HomebrewAudioRecording]

Never had that happen. If it passes the ACX check (plugin) it always passes (at least for me) in ACX.

[@EpicPlayzee]

@@HomebrewAudioRecording well i thinking i making mistakes in exporting audio|

[@virginiafrazier7947]

What is the URL? Can you paste it?

[@HomebrewAudioRecording]

URL for what?

[@reprogrammingmind]

@@HomebrewAudioRecording the plugin link FFS

[@coolbeans129]

, 👍

[@lamont8121]

wouldn't it be SO NICE if it was a pre-set and the capitalistic bureaucracy was just GONE ? Good grief. That ACX check feature should just get it done with a built-in preset. That ACX feature should NOT even be a plug-in...should be built in. Only in America does so many menus and clicks hide in the shadows, it seems.

[@HomebrewAudioRecording]

Well both Audacity and the ACX plugin are both free. So I'm thinking in this case, capitalism is not the issue.