Audio Dodo needs help please

No your doc file did not attach, I don’ t know if is because the file is too big, or if the message board refused to accept .doc files due to the virus risk.

I would suggest just cutting and pasting the text from the ACX emails into your next post.

a mate suggested a dropbox?

Dropbox is a company. The metaphor is a large wooden box along the roadway that you put something in and then somebody else comes along later and picks it up. You never meet. Many doctor offices use medical testing drop-boxes behind their offices.

The internet version of that is a server company that offers a digital wooden box.

As I recall, the early versions offered a modest amount of storage for free (to get you hooked) and larger storage is available on payment.

You can restrict access to your own home or office (friends of mine do that), or you can make the work available to anybody on Earth who wants it.

The company doesn’t have high interest for me because I’m a dot-com but for normal humans, it can be very helpful.


Sorry just found the replies

Here is from the ACX team.

Solorz, Brendan <>
Mar 24

Hello Robert,
The ACX Audio QA Team has encountered a problem with your recently-completed audiobook, “TRILOGY: Siam Storm”.

Title does not meet ACX Noise Floor Requirements.
Files have uneven noise floors, contain buzzing distortion and show signs of both gating and noise reduction. If possible try to isolate and solve any noise issues like hum/hiss/background noise/etc. in the recording stage. Once your voice has been recorded it can be difficult to remedy the issue, and noise reduction software can sometimes reduce the quality of the listening experience.

How To Submit Corrected Files:

Your title has been reset so that you may once again upload, replace, or delete files. Please be sure that only the final files are uploaded and appear in the order they are to be heard. Once you have uploaded corrected files, please be sure to click “I’m Done”.

Please be sure your submitted audiobook meets our requirements, outlined here:

The ACX Blog has a new section lead by Andrew The Audio Scientist, called “How to Succeed at Audiobook Production”.
Click Here for Part 1, which is all about Warm-Up and Recording.
Click Here for Part 2, which is all about Editing and QC.
Click Here for Part 3, which is all about Mastering.
Click Here for Part 4, which is all about Encoding and File Delivery.

The ACX Team


Brendan Solorz
Hello again,

The files all show signs of heavy gating. A more prominent example would be the Opening Credits file, you can hear buzzing and high noise floor issues only during area of narration, and then it cuts out in the spaces between words.

I hope this clarifies the issue a bit more. Thank you
Brendan Solorz
ACX QA Engineer

Hello Rob,

Here is a link to an ACX blog post on gating that includes audio examples.

Thanks for getting back to me and feel free to let me know when new audio has been uploaded and I will check it out.

Brendan Solorz
ACX QA Engineer

Hello again,

I have reviewed the resubmitted files but found that they still contain heavy buzz, “Chapter 1” and “Chapter 2” for example. This combined with what sounds like noise reduction artifacts makes the audio difficult to understand in areas.

I have unlocked these files for further revision. If you let me know what steps you took when revising your files previously, I may be able to offer more targeted advice, but in general noise floor issues should be resolved before recording, not in post-production, as the processing can sometimes further damage your audio. Unfortunately, the most likely solution would be to review all files to identify any areas that contain this buzz, then replacing the affected areas with new takes.

Brendan Solorz
ACX QA Engineer
Here is a link to an ACX blog post on gating that includes audio examples.

Thanks for getting back to me and feel free to let me know when new audio has been uploaded and I will check it out.

Brendan Solorz
ACX QA Engineer

to me, audio-team

Hello Robert,

I have reviewed your resubmitted files but still find that many contain buzz and other interference. One example would be “Trilogy - Chalice - Chapter 8”, which has high pitched buzz. Many of the newly submitted files also contain artifacts due to noise reduction that make the narration difficult to understand in areas. As I have said before, the noise floor of your submitted files varies in level from chapter to chapter, and so noise reduction affects each file differently as your signal to noise ratio shifts from section to section.

The only way to truly resolve these issues would be to adjust your recording setup in order to resolve buzz issues before recording, then replacing any areas with high level buzz with clean files.

I have unlocked this title for further revisions. Thank you

Brendan Solorz
ACX QA Engineer

Hello Robert,

The following files either have noise floors with high buzzing or other noise issues, or damage and artifacts due to noise reduction.

Trilogy - Siam Storm - Chapter 2
Trilogy - Siam Storm - Chapter 7
Trilogy - Siam Storm - Chapter 10
Trilogy - Siam Storm - Chapter 19
Trilogy - Siam Storm - Chapter 21
Trilogy - Siam Storm - Chapter 22
Trilogy - Siam Storm – Epilogue
Trilogy - Chalice - Chapter 2
Trilogy - Chalice - Chapter 7
Trilogy - Chalice - Chapter 8
Trilogy - Chalice - Chapter 18
Trilogy - Chalice - Chapter 19
Trilogy - Chalice - Chapter 21
Trilogy - Bimat - Chapter 2
Trilogy - Bimat - Chapter 3
Trilogy - Bimat - Chapter 4
Trilogy - Bimat - Chapter 7
Trilogy - Bimat - Chapter 10
Trilogy - Bimat - Chapter 12
Trilogy - Bimat – Epilogue

All files contain pops and clicks due to editing. Please also keep in mind that I have not listened to each file in full, so there may be additional files that contain buzz or other artifacts, which is why I recommend that you or someone you trust perform a QC check of your entire title.

We knew that ACX doesn’t listen to the whole production because they said so. This confirms that they do spot check manually. A couple of seconds listening to a buzzy voice is enough.

I’m going to go up and see the new video instructions. Andrew Grathwahl is “Andrew the Audio Scientist.” He appeared briefly on the forum but we fell out of love when our obsessive need for specific details exceeded his ability or willingness to provide them.

The older videos were helpful in a very general sense but tended to be short on If/Then instructions particularly in the studio. “Get rid of the buzz” isn’t helpful when you both know you have buzz and don’t know why.

We should remember that you are taking the place of a recording engineer who does know how to get rid of recording buzz.

They did provide a separate series of videos by John McElroy who does illustrate a studio and recording setup and has a specific list of hardware and software.

We will note that he’s fine right up to the end of the last video where he describes his recommendation for post production processing. I don’t agree with his ideas because of sound problems, and because they would be very difficult to achieve without a professional microphone in a studio. Maybe that was the idea.

I’m pleased they provided a chapter list of failures. Sometimes a company will get as far as the first failure and bounce the project. You fix that and the second one fails and then the third giving you the suspicion that they’re all going to fail and the project is far larger and more complicated than you thought.

One of Grathwahl’s videos stressed chapter-by-chapter matching. Nothing like flipping between the chapters and have them sound different. Past the odd surprise, sometimes it can be bad enough that the listener assumes the change is significant in the story. A theatrical plot point.

And it’s not.

So if you have a list of problem chapters, it may not be enough to just clean them up. They will then not match the unclean ones.

See? They thought you were using a noise gate, too. That’s just what it sounded like.
It’s really rough to take buzz and hiss out of a voice without affecting the quality. Just removing buzz from between words can have a choppy quality that they didn’t like and I probably wouldn’t like, either.

So it does seem we need to clean up the studio and record them again.


QC also mentions pops during editing. I don’t know that we got that far in evaluation. You can get that if you try to edit during a word or phrase, but you can also get that if you have a condition called DC offset. That can make a presentation almost impossible to edit.

That happens between words and can be really annoying. That can be caused by a broken microphone or computer.


In reading this I suspect that there may be some intermittent noise that is present in some of your recordings and not others. If you don’t have the originals, it may well be impossible to convert what you have into something that will pass muster. In neither of the posted samples did I hear anything I would characterize as “high pitched buzz”. The first sample “chapter2.wav” as already commented on sounds like an over-used noise gate, which is probably what tripped the ACX alarms in the first place. The second test clip has more noise than we would like in an original recording, and it’s not quite white noise, but it’s not a “high-pitched buzz” either.

Regarding the comment "All files contain pops and clicks due to editing. " This happens when splice two part together and there is a big difference between the two bits of the waveform. The resulting sharp edge comes through as a click. Use the “Find zero crossings” command to move your selects to the nearest zero crossing before doing a cut and this won’t happen. Such clicks can probably also be fixed by a post-process de-clicker.

So to back up a bit, tell us about your rig, what microphone, mixer?, computer interface, etc.

I would suggest taking a careful listen to “Chalice chapter 8” to see if you can hear the high-pitch buzz they are referring to, and if so post a sample for us.

would suggest taking a careful listen to “Chalice chapter 8” to see if you can hear the high-pitch buzz they are referring to, and if so post a sample for us.

And just because I haven’t been depressing enough, can you hear the buzz? We have one poster that just flat can’t hear well enough to tell whether the sound is damaged or not. I note that one ACX posting suggests that somebody else does quality control on your work before you submit it.

why I recommend that you or someone you trust perform a QC check of your entire title.


Thanks a lot everyone.

Still a daunting task ahead. I cant hear any buzzing. I have learned that the older you get you cant hear certain decibels maybe thats why I cant hear the buzzing I can hear a few pops though. I used a de clicker but maybe I set it up wrong
I cant hear any buzzes in chapter 8 but I put a bit in maybe someone can

I don’t have a rig or mixer (Dodo remember) I used a headphone mic and my trusty old acer.

My mates here as the same as me, they cant hear any buzzing either, but they are also fossils.

There must be some kind of processing associated with that microphone. Or maybe we’re listening to some of the processing you did earlier. I think ACX may have just run out of words to describe what they were hearing. I’m having trouble finding words to describe it.

Between the words it’s weirdly dead quiet, but during the words there is a sound like pouring dry rice onto a piece of paper. The word “Oh” at 7 seconds sounds like you’re leaking air while you say it. I can well imagine that to be an artifact of bad sound processing. We don’t know what was wrong with the original sound files, so we’re sifting through second-hand clues trying to piece it together.

Here. Make a new, short sound file according to this recipe:

Press Stop at the end, don’t do anything to it except Export and post it here.


I’m hearing a swish sound during “as to whether a mister”.
I’ve heard similar swish sounds as a consequence of Noise Reduction, ( although not via Audacity’s NR ).

There are also faint constant tones between 10.5kHz and 11.5kHz * , ( not caused by processing, they are artifacts generated during the capture ). Those tones can be removed with notch filters in Nyquist Prompt
spectrogram before-after notch filters applied.png
Nyquist Prompt with notch code.png

 (setf s (notch2 s 10365 50)) 
 (setf s (notch2 s 10558 50)) 
 (setf s (notch2 s 10751 50)) 
 (setf s (notch2 s 11136 50)) 
 (setf s (notch2 s 11519 50))

[ * older persons may not be able to hear such high-frequency sounds …

Presbycusis - Wikipedia ]

Window’s “audio enhancements” enabled perhaps. Could also be signal processing built into the microphone or it’s driver, optimized for skype or gamers, and not for serious recording.

What’s the make & model of the headset?

optimized for skype or gamers,

That’s my guess, but we’ll find out with the raw clip.