How I Make a Mashup (in brief)

I’ve posted two mashups on my YouTube channel. The first, in 2018, was a combination of “Feel It Still” by Portugal. The Man. and “Genghis Khan” by Miike Snow. The second, last week, is a mix of “good 4 u” by Olivia Rodrigo and “gec 2 Ü” by 100 gecs. It received a comment asking how I make a mashup, so here we are.

What’s a mashup?

A mashup is a combination of two or more songs, usually using some but not all elements of each song. For example, you might use the drums and guitar from Song 1, and the bass and vocals from Song 2.

What makes a mashup good is very subjective. :) It may be that the songs just fit well together, harmonically. It may be that the themes or lyrics of the two songs match up (or disagree in an interesting way!). It may just be that the combination of songs is humorous. Whatever the reason, if you like the mashup, then there’s probably someone else out there who does, too.

The idea for my new mashup was suggested by my friend Averly. I haven’t asked her what the inspiration was, though I like that the titles of both songs follow the formula [g word] [number] u. I just think that’s neat.

Sourcing stems

The first step in any mashup is to find stems. Stems are individual parts of a song (often groups of tracks) that are on their own. Stems give you the power to use individual musical elements of a song without just using them all. As an example, stems for some particular song may include vocals, guitars, kick, snare, hihats, bass, and effects.

Sometimes it can be hard to find stems for a given song. Some artists/labels will post them online, publicly. For example, stems for every song on the album 1000 gecs by 100 gecs are available at 1000stems.com. Other times, the stems are online, but not through official sources. It can take some poking around to find them. Reddit is sometimes a good place to locate stems, but in general a search engine is your friend. A good query to start with is [song name] stems.

Some songs just don’t have stems available at all. When this happens, the next best option is to try to find an “instrumental” and isolated vocals. People often post these on YouTube, and they can be found with a search. The command-line tool youtube-dl is useful for downloading these. :)

I prefer proper stems rather than just vocals and instrumentals, because stems give me more options. With the instrumentals, I get the entire song minus the vocals all in one inseparable file, whereas with stems I can be more choosy. But I’ll take what I can get.

Sometimes, neither stems nor instrumentals/vocals are publicly available. In this case, you’re pretty much out of luck. There are various pieces of software and plugins that can help you attempt to separate different parts of a song, but I think it can be hard to obtain good results from them. I would recommend choosing a different song for your mashup.

Stems are usually stored as separate audio files, one per stem. If you play them all back simultaneously in your music editing software, it should sound like the original song¹.

Matching key and tempo

The most basic thing to get right in a mashup is to make sure that the songs you’re using have the same key and tempo².

The key of a song defines which notes it is likely to use, and which note “feels like home.”³ If the songs you’re combining are in different keys, the harmony is likely to sound wrong, and not in a good way. To fix this, you can adjust the pitch of all of the stems from one (or both) songs, until everything is in the same key. If you don’t know how to figure it out yourself, an internet search will tell you what key a popular song is in. If, for example, Song 1 is in F major and Song 2 is in G major, then we could put them in the same key by pitch-shifting Song 1’s stems up by two semitones (which is the distance from F to G).

Your DAW should have a function to do this. DAW stands for Digital Audio Workstation, and it’s the program you use to edit audio, such as when creating an original song, or indeed making a mashup. Some well-known DAWs include GarageBand, Ableton, Reaper, FL Studio, and Logic.

Tempo refers to the speed of the rhythmic pulses in the music. It is usually measured in BPM, which stands for beats per minute. You need your songs to be in sync, which means getting them to share a common tempo. You can accomplish this by speeding up or slowing down all of the stems from a song (or multiple) until everything is at the same BPM. Your DAW should also have a function for this.

Tempo and key matching is the most important thing to make a listenable mashup.⁴ You must get them both right before proceeding.

Go wild!

Then, do what strikes your fancy! This is the stage where you get to arrange your mashup. You get to make creative choices — which vocal should appear when, what instruments are included at what points, and so on. Personally, I generally just follow whatever feels nice. I like to balance the vocals from both songs and get some interplay, and I think it’s fun to get vocals from both songs happening simultaneously near the end. I often aim to create something where recognizable elements of both songs are present throughout, so the listener is never just hearing one song.

The specific mechanics of how you arrange and edit your mashup come down to knowing how to use your DAW. As with most tools, your DAW will become easier to use with practice. And the more experienced you are, the easier you will find it to create your vision. Don’t be afraid to try things and observe the results.

When you have something you’re happy with, send it to someone you trust and ask for feedback. You don’t have to go along with everything they suggest, but it’s useful to have another set of ears on your work.

Once you’re finished, share it! I upload to YouTube because it’s pretty lax about copyright-type stuff. Without approval from the copyright holders, I believe that mashups are technically copyright infringement, but all that YouTube will do is monetize your video and send the money to the copyright holders through its Content ID system.

Mashups can bring new excitement and novel context to your favorite songs. Enjoy your creation!