Using digital keyboard to record multiple instruments voices

Hey guys,

I’m new here. I’m planning to buy a digital keyboard and a main feature I want is to play and record different instruments for the same song on the keyboard and have it all played together in Audacity, kind of like a one-man band thing. I have a few questions:

  1. What’s the best way to connect my keyboard to computer where the sound quality is optimal? I plan on just connecting directly to the keyboard.

  2. I would have to play each instrument (piano, drums, bass guitar, strings) separately, so I imagine having to create a separate recording each time. What would be the best way to play back my recording while I’m recording on a new instrument? Like playing back piano + drums while recording bass guitar onto that recording.

  3. Can you adjust the tempo and volume of your recorded instruments (tracks?) in Audacity? Let’s say I want bass guitar to be louder in a certain section in the song.

  4. Can you adjust the start time on the recording. Let’s say I want drums to come in a little later than I actually had played.


There are basically two approaches.

One is to make an “overdub” audio recording. To do that you would want a keyboard that has a “Aux” or “Line” output (in addition to the usual “headphone” output). You would connect the “line” (or “Aux”) output from the keyboard to a “line” input. Note that “mic” inputs found on most laptops are NOT suitable. Full size (tower/Desktop) computers often have a suitable “stereo line in” on the back of the machine - otherwise you could purchase a USB audio device that has stereo line input.

The other method is to connect the keyboard via MIDI. “MIDI” is not “audio”, it is “data” that passes “control information” to the computer - such as, what note has been pressed and how hard it has been pressed. With suitable software, the computer can then generate the appropriate sounds. Note that the significant difference with this approach is the you are not recording “sound” from the keyboard. The “sound” is generated in the computer. You can not use Audacity for this method - Audacity only works with audio. You need to use “MIDI Sequencer” software, such as Cubase, Sonar, Reaper or similar. Many modern keyboards are able to transmit MIDI data to a computer via USB, and often include basic MIDI sequencing software. If suitable software is not included, then “Reaper” is an inexpensive, full featured MIDI + Audio program.

The second (MIDI) approach is in many ways more versatile than the first (audio overdub) method.

Thanks Steve, I’m leaning towards the audio recording option. Can you link me to a USB audio device that has stereo line input that you’d recommend for this purpose?

We can’t really recommend specific hardware - there is a huge range to choose from and many competing manufacturers. I would say, don’t bother with anything under about $30 because it is probably not very good. I use a Behringer UCA 202, which costs around $30 - It is very basic - few features, just stereo line in, stereo line out and headphones out (no input level adjustment, so that has to be done with the keyboard volume control), but I find it works very well. Additional features will generally cost a bit more. We have a few reviews in this topic: but note that lists only a very few of the dozens of available devices.

Rather than [u]overdubbing[/u] where one layer is added at a time, most modern recordings are [u]multi-tracked[/u]. With multi-track recording, each instrument and vocal is recorded separately.

Often, several tracks are recorded at once and other tracks (such as vocals) are recorded later. Or, sometimes a backing-track is recorded first (such as the drums) and then the other instruments are recorded one at a time. Or, you can record several tracks at once and then if one musician makes a mistake, that one track can be re-recorded later. Or, you can record all of the instruments at once and record vocals later… etc.

A ‘click-track’ is often used (monitored in headphones) so that each take has exactly the same tempo. Then for example, you can use the guitar from take-2 and everything else from take-1, or you can use a few measures of guitar from take-2, etc.

With multi-tracking you can adjust the volume of each track separately and add effects separately (such as adding reverb to the vocals, or using pitch correction on the vocals, etc.) Typically “volume automation” is used to adjust the volume of different parts of each track differently (like Audacity’s Envelope control.

The MIDI applications mentioned by Steve are also DAW (Digital Audio Workstation) applications capable of multi-track audio recording. Multi-track audio recording is often combined with MIDI.

A few more comments on MIDI…

Since with MIDI you are not recording audio, the “character” of the synthesized instruments will be different from the sounds built-into your keyboard. And, since you are only capturing the notes & timing, you can take a MIDI recording and change from a piano sound to a saxophone sound, etc. You can also edit the timing or pitch one note at a time, or create MIDI completely in software without “playing” it on a musical keyboard at all.

It’s very common for home recording musicians to use MIDI drums (or for any instruments they don’t own or don’t know how to play). The one thing you can’t do with MIDI is synthesize vocal lyrics. (Apparently, MIDI guitar isn’t realistic sounding either.)

Most of the background music you hear in movies and on TV is MIDI… If you hear background-orchestra music in a modern movie or TV program, it’s very-likely not a real orchestra. MIDI is also used a LOT in pop, rap, & techno music.

Typically, you’d use your MIDI application to make an audio file (WAV, MP3, etc.) for “final release”. But your computer can play MIDI directly, and you can find lots of free MIDI files on the Internet if you want to hear some examples. When you play a MIDI file directly with your computer’s soundcard you are hearing whatever virtual instruments that come with your soundcard/driver, which are not the same quality as what you use with a MIDI sequencing application, but it can still sound quite good.

The downside to all of this stuff is that there is big learning curve for the software, and even after learning to use the software, music mixing & production can be very time consuming. With a professional recording, more time is spent in post-production (mixing & editing) than is spent recording. And, somebody who was arguing for using a real drummer once said, “A drummer can play a 3-minute song in 3 minutes. How long does it take you to program MIDI drums for a 3-minute song?”

There’s an article about recording multiple tracks in the manual:

Rather than overdubbing where one layer is added at a time, most modern recordings are multi-tracked. With multi-track recording, each instrument and vocal is recorded separately.

My Overdubbing sessions give me each instrument on its own track. Each pass records a new track and you can play the others into your headphones or not as you wish with the SOLO and MUTE buttons on each track.

Overdubbing doesn’t bolt each new instrument or voice into the show and you can never get it out. Direct overlayed and mixed performances is what happens when you set up your computer wrong.

Many computers do not allow you to listen to yourself during overdubbing. There’s an echo and you can’t stop it. The UCA-202 headphone connection can be set up for live monitoring as well as overdubbing playback. It’s one of the three physical devices certified for overdubbing as examples of how I did it. One microphone, one microphone adapter and one stereo line adapter (for use with an analog mixer). Other devices will certainly do this, but make sure before you write a check.


Thanks guys for your help. I bought the Berhringer UCA 202 and I’m ready to start recording via Audacity. I want to video tape myself. I’m assuming since I am recording audio separately in Audacity, how will I sync the video and audio files together? Can you recommend any free programs that can let me set the exact point in the video where the audio will start playing?

Almost all video editors allow you to adjust the point at which the audio starts.
Remember to give yourself a synchronisation point at the start and at the end of each video shot (see “clapperboard”)