Audacity 2.4.2 - ULAW Issue

Hi everyone.

I use Audacity a lot to create Cisco UCCX prompts and have had no issues till now.

it seems that when you export to WAV and select U-LAW it comes out as MLAW and UCCX will not recognize the format.

Codex is - PCM MU-LAW (mlaw)
Type - Audio
Channels : Mono
Sample rate 8000Hz
Bits per sample: 16

I have tried multiple version of Win 10, to see if it was a patch or something, And multiple versions on Audiocity but still no luck.

Anyone else had this challage?


:confused: This was working before and suddenly it is not? :confused:

So exactly what were you doing before and what has changed and how ?

This page will check the format for you:

I’ve just tested a μ-law file exported from Audacity.
Here’s the analysis:

Complete name : untitled.wav
Format : Wave
File size : 234 KiB
Duration : 30 s 0 ms
Overall bit rate mode : Constant
Overall bit rate : 64.0 kb/s

Format : ADPCM
Format profile : U-Law
Codec ID : 7
Codec ID/Hint : CCITT
Duration : 30 s 0 ms
Bit rate mode : Constant
Bit rate : 64.0 kb/s
Channel(s) : 1 channel
Sampling rate : 8 000 Hz
Bit depth : 8 bits
Stream size : 234 KiB (100%)

Hi. I am on Audacity 3.0. I recorded an IVR and was told to just submit as a .wav file. I’m new so didn’t know what to ask so edited the audio and it was set at my normal 44100 Hz and 16 bit. They loaded the audio and when I dialed the phone number to hear my recording the quality was poor and didn’t match the quality I submitted. I inquired and they said they had to change it to 8000Hz to work with their system. So after research I see something called U-Law that appears to need 800Hz and 8 bit.

So I’m in need of an expert to assist with what to do. If I record in 44100 Hz and 16 bit is it possible to save that file in 8000Hz and 8 Bit or do I need to set up Audacity in advance at 8000 Hz and 8 Bit and re-record it? If I can literally resave it at 8000Hz and 8 Bit I don’t see how to do that.

Does anyone know what exact questions I need to ask the client about their system in order to ensure I save the recording and set it properly?

Yes, you can do that.

  1. Immediately before exporting, change the “Project Rate” (lower left corner of the main Audacity window) to 8000.

  2. If your recording is stereo, you can convert it to mono with “Tracks menu > Mix > Mix Stereo Down to Mono”.

  3. When you “Export as WAV”, change the “Encoding” setting to “U-Law”.

Note that the sound quality of 8-bit / 8000 Hz is noticeably less than 16-bit / 44100 Hz.