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Recording an Electric Guitar or Bass without an Amplifier

This is an assignment for the Coursera course Introduction to Music Production

[Meta] Introduction

Hi, I’m Sungwon. I grew up in the United States, have been in South Korea the past 9 years and am now living in France for the time being. In this post, I’ll be explaining how to record an electric guitar or bass without an amplifier as Assignment 1 for Week 1 of Introduction to Music Production.

Recording an Electric Guitar or Bass without an Amplifier

Alright, let’s get down to business.

M-Audio ProFire 610 Audio Interface

M-Audio ProFire 610 Audio Interface

There is fundamentally only one way to record an electric guitar without an amplifier. And that is by direct recording using an audio interface (as opposed to mic-ing a guitar amp).

When the guitarist plays a string, the vibration of the string is picked up by the pick up (get it?) of the guitar. The pickup acts as an input transducer, translating the movement of the string into a voltage signal. This signal is then carried along the length of the guitar cable (also known as a 1/4 inch TS cable).

Audio Interface: From Analog to Digital

To get this signal into the DAW (Digital Audio Workstation) of a computer, we need to convert the analog voltage signal into a digital (binary) representation. The audio interface plays this role. It has a preamp which brings the guitar signal from the cable up to line level and then it samples the analog signal at a given bit rate to convert the analog signal into a digital one that can be used in the DAW.

Caveat: 1/4 inch TS instrument cables are unbalanced, practically meaning that they are prone to noise and interference. In a recording situation especially, noise is bad! To reduce noise, the shorter the guitar cable the better. If the audio interface is at somewhat of a distance from your instrument in the studio, a direct box can be used. A direct box acts as an interface between an unbalanced, noise-prone TS cable and a balanced XLR cable which is more noise resistant and is also accepted as an input in most audio interfaces.

Monitoring without an Amp

A significant problem with recording without an amp is that it may increase the difficult of monitoring, i.e. listening to the instrument being record. If we monitor the instrument from within the DAW, there is significant latency from when the player plays a note to when it is heard through the DAW due to the signal processing time required. This can be distracting and confusing to the player, resulting in degraded performance for the recording.

The best solution is to monitor the sound of the instrument before it gets into the DAW. There are two main options.

  1. If you actually have an amp available, but just don’t want to use it for recording, you can use the amp as a monitor by using a direct box. With the guitar as input, the direct box can output the signal to both the audio interface for recording and the amp for monitoring.
  2. Another solution may be provided by your audio interface. Many audio interfaces include a headphone out for monitoring the signal directly from the audio interface’s preamp.
  3. Finally, your audio interface may also have line output for a home stereo system. This solution is least desirable, however, because consumer speakers are designed to enhance the listening experience. That is, they will not reproduce the input signal faithfully and will give an inaccurate impression of the sound of the instrument being recorded.
The entry-level audio interface M-Audio Fast Track has both a headphone out for monitoring as well as line output

The entry-level audio interface M-Audio Fast Track has both a headphone out for monitoring as well as line output

 

[Meta] Reflection

This assignment was not as difficult as I first imagined. I was in the middle of rebuilding my personal website which I thought was good timing for this assignment, but getting the site ready ended up being the hardest part. I was a little worried the site wouldn’t be ready for this assignment, but I was able to resolve the technical issues I had. As for the content itself, I was also a little surprised that I didn’t have to review very much of the course material and that most of it was still fresh in my mind. I’m interested in trying out some screenmovie software next time.

Thanks to my fellow students for peer reviewing this assignment!