Stem export audio as 1 channel mono

Getting Stuff Done How do I .... ?
#1

Hi it’s me again,

My mastering client got back to me a little angry that I sent them back their mastered files as 2 channel audio files. Mind it is mono info, just over 2 channels. They insist that I give them one channel audio files. Now after doing 30 hours of mastering in 3 days I have no will left to argue, is there a way I can stem export and get one channel audio out of it?

Or am I faster writing a bash script using ffmpeg to do it?
Thank you

#2

Not directly. But to clarify, you have 2in/2out tracks with the same signal on both channels?

#3

at export, I get a track with two identical channels yes. In ardour the track is a mono track, one in, one out, panner disabled.

#4

Right click the track/bus header and uncheck Strict I/O

#5

When you enable “Apply track/bus processing” then you will indeed get a stereo file (or as many channels as the track has outputs).

There are two ways to get a mono file from a mono track

  • disable FX processing (you will get a stem only with edits, no channel plugin processing)
  • remove the 2nd output port from mono tracks - right-click on the track’s output connection button and in the port-matrix remove the right channel:

image

–

I think we an option to a stem-export with processing just before the panner, and perhaps also allow to split channels to separate files (like normal export does).

#6

Thanks, but it won’t let me remove it from the mono tracks. only the master bus. Which causes horrible audio defects.

I’m trying to make an ffmpeg script to do solve my problem for now, but I’m not great at shell scripting either. I gotta deliver soon too. And if I tell them “sorry my DAW limitations make it that I can’t export your files as mono” I’m pretty sure I will not be getting any more work from them.

#7

From what I understand this simple sox line should convert your 2-channel mono file into a 1-channel one

sox signal_stereo.wav signal_mono.wav remix 1,2
2 Likes
#8

Did you try my suggestion?

Here’s a script I use that will split a folder of stereo files.

#!/bin/bash

# Check if the number of arguments is correct
if [ $# -ne 1 ]; then
  echo "Usage: $0 <directory_of_stereo_wav_files>"
  exit 1
fi

# Get the directory path from the first argument
input_dir="$1"

# Check if the directory exists
if [ ! -d "$input_dir" ]; then
  echo "Error: The provided directory does not exist."
  exit 1
fi

cd $input_dir

# Create a new directory for the output files
mkdir -p mono
output_dir=$(realpath mono)

# Loop through all the stereo WAV files in the input directory
for stereo_file in "$input_dir"/*.wav; do
  # Get the filename without extension
  filename=$(basename "$stereo_file" .wav)

  # Use sox to convert the stereo file to a mono file using the first channel
  output_file="$output_dir/$filename.wav"
  sox "$stereo_file" "$output_file" remix 1

  # Check if the conversion was successful
  if [ $? -eq 0 ]; then
    echo "Converted: $stereo_file -> $output_file"
  else
    echo "Error converting: $stereo_file"
  fi
done

echo "Conversion completed."
2 Likes