One Hour Compo celebrates it's 400th round on Thursday June 9th at 9:00PM EST! Don't miss it!

Compo is a slang word for "composition competition" commonly used by the arrangement community. It is derrived from the demoscene competitions by the same name. Contrary to this, compos are less of a competition and more of an excerise in composition abilites. Each compo has it's own unique format and guidelines and while some are as short as 1 hour, others can last anywhere from a month, to a few months. It's important to remember that the primary purpose of compos are to hone your skills and abilites by working within, sometimes very constricting, guidelines. These techiniques have proven essential to the growth of countless musicians.

Remember: the only way to lose a compo, is to not participate.

Recent Compos

Weekly Homework Composition

19th Weekly Homework Compo (WHC19)  Active

21 hours, 35 minutes ago

This week we explore the first species counterpoint with atmosfaere:

First Species Counterpoint

Counterpoint is the art of combining multiple melodic lines.
The goal of this exercise is simply to write two melodies that sound good on their own but still sound good and independent when played at the same time.

Write two different sections of counterpoint using only half notes (Each note of both melodies starts and ends at the same time for first species counterpoint). Do the second section in a different mode (major, minor, lydian, etc..).

There are many rules that are followed to ensure that the lines maintain their independence. You don’t need to know or follow all of them for this exercise (at least try to make sure they sound independent by ear), but I will go over the most important ones below.

Parallel motion:
The more that the two lines move in the same direction, the less they sound like separate parts. Do not move from two notes that are separated by a fifth or an octave to two new notes that are also a fifth or an octave apart, this destroys the independence of the parts.

Voice crossing:
Have one line be higher and the other lower. Having the lower line go above the higher line is not good for independence of the voices. Do it sparingly for this exercise. (I don’t think it is much of a problem when the voices have different timbres but it is something to keep in mind)

Try to avoid repeating notes. It will make one of your lines melodically subordinate to the other. It weakens the melody of that line.
Unison: Don’t use the same note at the same time in both lines except at the beginning or the end.

Have the melodies reach their peak at different times.
Have the lines end on the fundamental note of the scale (can be separated by an octave) to give the melodies a strong resolution and unity. Occasionally one line can end on the fifth, but try to avoid this.
Often the beginning notes belong to the root position triad (fundamental, third, and fifth). I imagine this helps set the key and gives unity to the melodies. The lower line should probably be the fundamental note at the beginning. Have the relationship between the starting notes be unison, octave or fifth.
Don’t have harmonies of fourths in first species counterpoint. Apparently it is unstable, but I will have to experiment with it to try to understand.
Consonant “harmonies” between notes are 3rds, 5ths, and 6ths. This refers to the interval between two notes being played at the same time, not the interval of the notes in relation to the fundamental.
Dissonant “harmonies” are 2nds, 4ths, and 7ths. It is possible to use these if you can resolve them effectively.


Composing First Species Counterpoint
Composing a Cantus Firmus (well formed musical line)
Rules of First Species Counterpoint
More info with notated examples
Concise Rules
First Species with modes
Melodic writing and counterpoint

All Five Species

  • Start: 22 hours, 2 minutes ago
  • Deadline: 6 days, 9 hours
  • Voting Ends: 1 week, 6 days

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190th 2HourTrackSundays Event (2HTS190)  Voting

1 day, 4 hours ago

Here is this week's theme video:

The participants have two hours to make a song and additional 15 minutes are granted for mastering and uploading. The chat happens on

  • Start: 1 day, 1 hour ago
  • Deadline: 22 hours, 17 minutes ago
  • Voting Ends: 5 days, 21 hours

View Round
People's ReMixing Competition

The 7th Saga - Boss Battle (PRC362)  Active

2 days, 10 hours ago

Source: The 7th Saga - Boss Battle (SNES)

"Let's do the boss battle music from The 7th Saga"

Deadline is Wednesday November 29th 2017, 10:59 AM ThaSauce Time (18:00 UTC, 19:00 GMT).

Check the following site for the rules:

Check the Ocremix thread for more information (you can post questions there. It is also the place to post a song if you're not able to use this page):

After uploading, please check if your song plays and can be downloaded and played without problems.
Only upload MP3 Files.

It is not necessary to use ThaSauce. You can upload the song anywhere you want, but I must have a download link. So if you use SoundCloud, don't forget to allow downloads, otherwise your song does not count as an entry or bonus mix. I will still use ThaSauce as a possible place to submit songs and upload all the songs to the ThaSauce page to have the songs at one central place.

If ThaSauce is down, please also submit the song somewhere else with a download link and post the link in the Ocremix Thread.

The winner of this round may select the source for PRC365 which is the first from the new season next year.

  • Start: 2 days, 10 hours ago
  • Deadline: 1 week, 2 days
  • Voting Ends: 2 weeks

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One Hour Compos

One Hour Compo - Round 475 (OHC475)  Voting

3 days, 21 hours ago

Tonight's theme is a picture theme. Please see the resources below.

You will have 1 hour to complete your song and 10 minutes to finish it up. You will then have an additional 10 minutes to upload your song. At 6 PST/9 EST you may begin your mixing, please have your files uploaded by 7:20 PST/10:20 EST. Join us for discussion in #thasauce on

  • Start: 3 days, 19 hours ago
  • Deadline: 3 days, 17 hours ago
  • Voting Ends: 3 days, 4 hours

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189th 2HourTrackSundays Event (2HTS189)  Completed

1 week, 1 day ago

Here is this week's theme video:

The participants have two hours to make a song and additional 15 minutes are granted for mastering and uploading. The chat happens on

  • Start: 1 week, 1 day ago
  • Deadline: 1 week, 1 day ago
  • Voting Ends: 1 day, 1 hour ago

View Round