Fixing an ACX Issue

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Re: Fixing an ACX Issue

Post by TJB » Fri Dec 25, 2020 7:22 pm

Koz, I'm searching for the holy grail on Christmas morning. Given our issue with the first sec and trailing 5 secs which, allegedly contain noise (but unseen on the sound track), what about this for a suggested workflow:

First, independently record about 10 secs of quiet 'room noise' ... then save this as a wav file for use later, again and again
. open a new track and do the recording
. then copy the room noise file (above) and paste in the beginning and end of the recording
. then do the mastering (filter curve, RMS, Limiter, Hum Remover and Noise Reduction
. review the entire track and remove all visible clicks, etc
. then save as a wav file Edit Master and export as an MP3 file

If this is the way to go, then I'm assuming I could always just use the recorded room noise above and paste into any new document prior to mastering

Does this make any sense or am I off base?
Thanx, Tom

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Re: Fixing an ACX Issue

Post by kozikowski » Sat Dec 26, 2020 3:06 am

I'm not sure where to go with this. Using a pre-packaged selection of noise is dangerous. If anything in your studio changes, the beginning, end, and middle of the chapter aren't going to match. You are warned not to leave the studio during the recording because your body is part of the sound personality of the room.

I'd be much more likely to to put three to five seconds of silence at the beginning, then take a breath and start reading. Use the silence before the breath as the silent performance for that chapter if you need it to cover up mistakes. Alternately, put more than five seconds of silence at the end, copy a second of it to the beginning and trim the end down as needed.

Do one of these tricks to a short chapter and make sure you can't hear the edits. If you can hear them, ACX will be able to hear them.

Do you need to use a Hum Remover? That's usually a red flag you have recorder problems.


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ACX Check selection limit in v2.4.2

Post by pato » Mon Jan 11, 2021 10:21 pm

I record spoken voice using Win10 at 44,100hz 24 bit mono on a 2 year old desktop computer with an i5 chip and 8Mb RAM.. I've long used ACX Check on tracks up to about 25 min long with no problem. But after recently upgrading to v2.4.2, ACX Check seems to work only for tracks (or selected segments) up to about 20 minutes long. For a 24+ minute track it yields message "Processing complete" but no visible results display.

Why is this happening? Feature or bug? Apparent user error? Solution?

Note that the Audacity wiki states that the max selection length is about 2.14 billion samples (13.5hrs at 44,100).

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Re: Fixing an ACX Issue

Post by steve » Tue Jan 12, 2021 1:02 am

pato wrote:
Mon Jan 11, 2021 10:21 pm
ACX Check seems to work only for tracks (or selected segments) up to about 20 minutes long.
You need the updated version of ACX Check for Audacity 2.4.2. Get it here: ... #ACX_Check
9/10 questions are answered in the FREQUENTLY ASKED QUESTIONS (FAQ)

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