Roland TR-505

Content sourced from Wikipedia, licensed under CC BY-SA 3.0.

The Roland TR-505 Rhythm Composer is a drum machine and MIDI sequencer released by Roland in 1986. It’s part of the same family as the famous TR-909 and TR-808, and it adds Latin percussion sounds from the TR-727. The 505 uses 8-bit PCM samples stored at 25 kHz, giving it a classic, lo-fi drum tone.

Key points in plain language:
- Voices and sounds: 16 drum sounds are built in, but only 8 sounds can play at once (8-voice polyphony).
- Patterns and songs: 48 factory patterns and 48 user patterns are available, organized into three pattern groups for factory patterns (A–C) and three for user patterns (D–F). You can arrange up to six tracks (or “songs”) using these patterns, with a maximum length of 423 bars.
- Pattern structure: Each pattern is one measure long (usually 4/4 with 16 steps). You can edit steps, copy, insert, or delete steps and patterns. Patterns can be chained together so you hear several patterns as one long pattern.
- Rhythm editing: An accent lets you boost the volume on a specific step. Voice editing is limited to global settings like volume, velocity, MIDI channel, and MIDI note for each voice.
- Tempo and feel: Default timing is 4/4 with 16 steps per pattern, but you can change the length and scale to create swing or shuffle rhythms.
- Pads and interface: 16 performance pads (not velocity sensitive), plus a simple LCD, 15 buttons, 2 knobs, two main outputs (left/right or mono), a headphone jack, and tape input/output for storing data externally.
- MIDI and sync: MIDI in/out, start/stop foot pedal jack, and MIDI can be transmitted on channels 1–16. It supports MIDI Omni mode to receive all data.
- Memory and storage: The machine can store 48 ROM patterns and 48 RAM patterns, 6 tracks, and up to 423 measures. It can also save data to tape via its tape interface.

Notes for enthusiasts: There are DIY guides that describe circuit bending and modifications to change samples, add extra outputs, or introduce CV/pitch options for more experimental uses.