Roland TR-505
Rhythm Composer (1986)

 

Budget portable digital drum machine with crunchy samples and a classic sequencer.

The 505 is a scaled-down version of the classic Roland TR-626 with less features and sounds.

DRUM MACHINE Main panel features a simple LCD display, 15 buttons, 2 knobs and 16 trigger pads (no velocity).

Rear panel terminal connectors:
- main signal out
- headphones
- pedalswitch input for start / stop
- Midi interface
- tape interface.

Power supply is a 9V external PSU 100 mA with -) plarity or 6 X 1.5V batteries.

VOICE main core 8 bits CPU Roland R15179247 basically a HD6301 derived from classic 6800 manages 8 channels polyphony.
Each voice features and assigned sample PCM which edit is limited to volume parameter and several polyphony restrictions :
- 1 tom per time (or timbale)
- rimshot OR clap
- 1 conga per time
- 1 cowbell per time
- crash OR ride.

 

SAMPLES wavetable is 128 KB ROM (at IC11) which contains 16 PCM samples at 8 bits depth 25 kHz rate .The internal samples are mostly standard drums from this era with some extra ethnic samples, very similar to Roland TR727 set.
TECH: seems to be some third part project to replace or expand the original ROM with some alternative romset like Oberheim DMX, Linn Drum ...

 

Low Conga	Hi Conga	Timbale	Low Cowbell
Kick	Snare	Low Tom	Mid Tom

Hi Cowbell	Clap	Crash	Ride
Hi Tom	Rimshot	CL Hihat	OP Hihat

SEQUENCER the 505 features 2 recording modes:
- step mode
- real-time note insert.
Step numbers can be changed for other scale time (default is 4/4) and variable odd tempo.
Some classic edit functions such as accent, insert, copy or delete.
SYNC internal frequency from 40 to 240 BPM or slave mode to external Midi clock.

 

 

MIDI is limited to note on/off and 5 velocities and Pads can trigger assignable Midi notes (but no velocity).
NOTE: No sysex dump implementation.

 

 

MEMORY :
- 48 ROM patterns
- 48 RAM patterns
- 423 measures
- 6 songs.
Patterns and songs can be saved only to tape using the appropriate interface.

 

 

MODIFICATION my mod: I added 8 triggers out that drive some percussive modules like Simmons SDS. Other common modifications are samples pitch tuning and circuit bending (I did this work on the tr-626 which is pretty similar- you can check it HERE)

 

Trigger out mod

RELATED FAMILY:

	Cr-1000 a kind of preset version of the TR505 with same PCM sounds but it lacks the sequencer.
	TR-626 - includes all 505 sounds plus others, also more features and options like pitch tuning and separate analog outputs.
	Tr-707 previous mo del, also all digital. Exists also in a latino percussions version model TR-727.

 

 

VST PLUGIN / SAMPLED VERSION there are some free and commercial samples set:

	name	price	demo
	machines.hyperreal sonof8bits VST planet	FREE sample pack	n/a
	DJ Quartzlocker	FREE (distorted tr505)	n/a

 

AUDIO DEMO:

	shake the TR505 with Roland D-50
	custom pattern 1
	custom pattern 2
	roland pattern 1
	roland pattern 2
	roland pattern 3

 

VIDEO CLIP SELECTION Composer Demo with Boss Dr-110 Circuit bending

 

ROLAND TR505 MANUAL

Roland TR-505 SERVICE MANUAL

brochure picture

A gallery of weird BENT 505 from BURNKIT 2600