TIA Arpeggio Tips

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Nothing screams chiptune quite as loudly as a lightning fast square-wave arpeggio does. This guide will cover arpeggio basics, and how to maximize arpeggio effectiveness with TIA, a chip that is out of tune and only has 2 voices.

Arpeggio Basics and General Tips

The arpeggio is a musical technique where notes in a chord are played in sequence. It was first used on harps, where it's difficult to play many notes simultaneously. The intent of the arpeggio is a sort of chord approximation. Unlike a chord, one definitely hears the notes being played separately, but the arpeggio usually plays quickly enough, or is positioned as a more subtle backdrop, so that the arpeggio notes and their relationships indirectly wash over the listener, rather than being intently followed.

The repeated arpeggio sequence will usually move to different root notes within the song, in a manner similar to chord progression.

One thing to be mindful of is a fast arpeggio has the benefit of adding a sense of energy to the music, but this can be a double-edged sword. A fast arpeggio played throughout a song can be fatiguing. Instead of running a fast arpeggio throughout your whole song, it might be best to leave it for specific parts that benefit from the added energy.

Also consider that you don't need to run an arpeggio at maximum speed and volume to receive its benefits. Examples of slower and more subtle arpeggios can be found in unsuspecting places, such a Louis Armstrong's What A Wonderful World and R.E.M's Everybody Hurts.

TIA Arpeggio Tips

The obvious limitation to deal with is TIA's infamous lack of tuning. To best way to start out managing this is to either use Perceptual Tuning or Tune2600.

One typical arrangement for an arpeggio is to play the notes in a major chord. This means the root note is played, a note 4 semitones above the root, and another note 7 semitones above the root. If the root note is C, this would translate to the C, E, and G notes. In certain situations the note 4 semitones above the root will sound off-tune. If you run into this, one possible solution is to instead play the root, the note 7 semitones up from the root, and another a full 12 semitones up from the root (C, G, and C, for a root note of C) which has similar consonance.

Another issue commonly run into with quick arpeggio's on TIA, is they'll monopolize an entire voice. This is bad enough on other chiptune platforms with 3 or 4 voices, but highly limiting with TIA's 2 voices. This can be rectified by ensuring the first note the arpeggio plays is a rest, which means the same voice is available for a drum hit or other brief sound. Using a rest has little to no effect on the quality of the arpeggio, as there is almost always a related note playing melody on that beat. In our previous example with a root at C, this means we'd play the notes REST, C, G, C , or REST, C, E, G, in our major chord arpeggio.


TIA Arpeggio Tips was written by Mike Saarna (aka RevEng) as original content for 7800.8bitdev.org.