Roland TR-909

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Roland TR-909

The TR-909 was a partially analog, partially sample-based drum machine built by Roland Corporation in 1984. Being the brainchild of Tadao Kikumoto, the engineer behind the TB-303, it features a 16-step music sequencer and a drum kit that, at that time, aimed for as much realism as was possible.

Like the TB-303, the mark of realism was missed by a few miles due to technical constraints, and this showed when the machines were blown out for low prices before the hype of techno and acid began; sample-based drum computers were better at faithfully reproducing real drum sounds, whilst the TR-909 sounded synthetic.

The drum kit contains the following sounds:

All drums except for the hihats and cymbals are synthetically generated; there is an oscillator circuit with a dedicated filter and envelope curve. The hihats and cymbals are 6-bit samples, compressed and combined with a volume envelope curve to allow slight modification. Thanks to the analog circuitry, various aspects of the drum sound can be modified (pitch, attack, decay).

There is also a feature called "accent"—a primitive means of humanizing the drumbeat. In a simplified model of a drummer and a kit, the loudness of the sound created would basically depend on the velocity at which the drummer hits a given part of the kit. A human drummer can emphasize certain notes by playing them louder, and the accent parameter provides a means to boost a particular step. A more complex model would also include timbral change, but reproducing this effect using the TR-909's analogue electronics wasn't feasible. It took the industry a while to even offer this effect in sample based drum machines, due to the price of sample memory and the number of samples one would have to take to faithfully reproduce it.

Part of the charm of the TR-909 comes from its 16-step sequencer—today it might look primitive, not allowing subtle grooves and being limited in variety with only 16 steps, while a more lively, complicated drum pattern might need much more than that. On the other hand, punch the buttons 1, 5, 9 and 13 on the bassdrum part, and you have just programmed a 4-to-the-floor beat. While the sequencer is running, a light runs from step 1 to step 16.

The TR-909 has several editing modes: pattern editing where one focuses solely on the 16 steps, and track editing, which allows for chaining various patterns in a row. Because it has MIDI, it's also possible to control other instruments with the sequencer.

This machine and its unique sequencer (both Roland and other manufacturers used either a grid-based sequencer, showing the dots on an LCD, or another method that did not display the pattern at all) were the basis for so-called grooveboxes—self-contained compact synthesizer workstations with rudimentary keyboards and pattern-based sequencers, aimed at creators of electronic music, using sample-based sound generation and a number of realtime controls.

Other manufacturers have made similar devices. These are:

Not everyone needs the sequencer, so the sounds are also available in convenient 1U high rack units:

(Grooveboxes are not included in this list as they contain more than just drums, though they may have copied the principle of the 16-step sequencer.)

External links

nl:TR-909 ja:TR-909 sv:Roland TR-909


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