Audio Recording

This is a tutorial on how to get started recording musical instruments to your Linux computer using Audacity which is a free recording software. First, make sure you have the following requirements:

1.) Linux Ubuntu with Audacity installed.
2.) Any musical instrument such as electric guitar, etc.
3.) Any outboard mixer (will do the pre-amplification) such as Behringer Xenyx 502. You can read more about that here:
http://www.youtube.com/watch?v=ubTk7RqbXWs. You can buy this mixer at Amazon

4.) PCI Soundcard (onboard soundcard not recommended). This should be correctly installed first. If you can play music through your Rhythmbox music player then your soundcard is correctly installed.
5.) Audio cables to connecting instruments/equipments.

Step1: Recording Setup

1.) Connect your musical instrument to your outboard mixer such as shown below:

Connect the bass guitar cable to any line input on the mixer such as “Line In 2/3” shown above. You will not be using the microphone cable since you are recording any vocals. It is not advisable to directly connect your musical instrument to your soundcard because you cannot get a quality sound recording signal. It will sound very weak and with a lot of noise.

2.) Connect the mixer main output (left and right) to your soundcard input (see screenshot above).

Step2: Configure Audacity to accept the Recording Inputs

This tutorial is using Ubuntu 10.04 operating system but it can as well be applied with other versions of Linux. This tutorial does not use JACK as the connector. But the use of JACK when recording will be covered in the future tutorials. Refer to the steps below:

1.) Go to System – Preferences – Sound and click the Input tab. It should use the “Analog Microphone/Line-In/Microphone” input as the connector. See screenshot:

2.) The next thing that you will do is to launch Audacity. Go to Edit – Preferences. Click “Devices” tab. Make sure the following is set:

Host: ALSA
Playback device: default
Recording device: default
Channels: 1 (mono)

3.) Click “Recording” tab in Edit – Preferences. Check “Overdub” and the set “Audio to buffer” at 100 ms as well as the latency correct to -130 ms. Uncheck “Sound activated recording”.

4.) Click “Quality” in Edit – Preferences. Select a “Default sample rate” of 96000Hz. Then the Default sample format of “24-bit”. This ensures the best quality of your recorded sound wave. Screenshot:

5.) Go to “Tracks” in Audacity Preferences (Edit – Preferences). And make sure that the Default View mode is set to “waveform (dB)”.

6.) It’s time to test if Audacity is actually detecting the soundcard inputs. In the Audacity recording environment, look for a microphone symbol. It has a drop down and click on it. Click “Start monitoring”. Screenshot:

7.) Try playing your musical instrument. Audacity should capture the line level inputs from the sound card. Make sure it won’t clip. You can see it in the Audacity input volume meter above the microphone symbol. If the volume is too low. Adjust your outboard mixer main volume output.

Note: In some rare instances you won’t be able to monitor the output of your musical instrument out of your computer speakers. But you can still record it in Audacity. Make sure the input volume level meters of Audacity are detecting your inputs.

Step3: Start the recording

Once everything is ready, you can confidently start the recording.

1.) Hit the record button of Audacity, it will start capturing the recorded signals.
2.) Play your musical instrument. As a demonstration, I tried doing the above steps with my favorite musical instrument- a jazz bass guitar.

3.) After recording, you should see the captured sound wave on the Audacity editor.

4.) You can as well create a multitrack in Audacity. Simply position to starting line to any part of the audio then click record button.

5.) To mixdown or combine tracks. Select all clips then go to Tracks – click “Mix and Render”. It will combined all your recorded tracks into one.

Note: Since your mixdown is 24-bit/96Khz resolution, you should use a quality sample rate converter/dithering software to convert it to 16-bit/44.1Khz resolution. Then once it is in 16-bit/44.1Khz resolution, you can then convert it to MP3 using LAME encoder. Below is a sample sound recording of a bass guitar solo done using Audacity in Ubuntu: