DIN Sync carries timing and run/stop state, not notes, patterns or audio. The TR-606 can be the output device and the TB-303 the follower, but both continue to read their own memories and create their own sound. Changing the 606 pattern does not select a bass pattern, and changing a bass note does not alter the drums.

This separation is why the pair remained useful after its practice-band marketing failed. A player could replace either half, route the trigger outputs elsewhere, process each audio stream separately and keep the whole rig locked. The system was small, but it was already modular in behaviour.

Pre-Scale changes what each numbered position means. The manual illustrates straight and triplet relationships rather than assuming every pattern is sixteen equal semiquavers. Last Step shortens the measure, so a pattern can cycle in two, four, eleven or any other available number of steps instead of waiting for key 16.

Accent is programmed like another instrument, but it is not another sound. When an accented step arrives, the shared accent circuit raises the voices occurring there. Because several instruments may occupy the same column, one accent can turn a kick-hat collision into the beginning of a phrase.

In Pattern Play, holding neighbouring pattern keys asks the machine to play them in sequence. This is the quickest route to an A/B phrase: write a stable bar, copy its logic into the next location, change only the final beats, then select both. Track Compose formalises the same idea by storing pattern numbers and repetition counts.

D.C. repeats the whole track. D.S. and its mark repeat a chosen section. These are not ornamental score references: they are memory-saving arrangement commands inherited from written music, allowing a small amount of CMOS RAM to describe a longer performance.

Tony Bacon's February 1982 review records how this felt before the machine acquired a mythology. At £199 including VAT, the 606 was presented as a composing tool: write the rhythm on paper, enter it carefully, chain related patterns and then order them into tracks. His criticism of the cymbal sits beside a much larger conclusion—that the little box rewarded preparation and musical thought rather than one-button accompaniment.

Start with only bass drum and remove external effects. The circuit should produce a concise low body whose pitch falls into a short decay. If the trigger clicks but the body does not ring, trace the two IC15 oscillator sections and their surrounding capacitors and resistors before adjusting output level.

Next isolate snare. Its pitched component and noise component travel through different parts of the circuit before they meet. A snare with body but no spray points toward the white-noise or high-pass path; noise without body points toward the oscillator and attack section.

Finally compare closed hat, open hat and cymbal. If all three lose their metallic complexity, suspect the common IC16 oscillator bank or its supply. If closed hat works but open hat does not, the shared source is already proved and attention can move to the open-hat trigger, envelope, choke and VCA stages.

For calibration, the factory sequence is evidence, not an invitation to turn every trimmer. The service notes first establish CPU clock, interrupt clock, tempo range and noise level. Power rails and trigger integrity should be measured before changing any internal adjustment.

Choose one master clock. Set the TR-606 Sync switch to OUT when it should lead, or IN when it should follow. Confirm run/stop first, then listen for stable tempo over several minutes. A DIN cable can preserve one function while losing another because transport and clock occupy different pins.

Do not feed a trigger output into an audio input. The HT and LT sockets carry short control pulses, not sound. Use equipment designed to accept an external trigger, and verify its voltage tolerance before connection; the 606's pulse is substantially higher than a modern 5-volt logic signal.

The trigger lanes remain normal musical lanes inside the pattern. This is composition as routing: an audible high tom can double a synthesizer note, or the tom level can be reduced to zero so that only the external event remains. The sequencer is controlling two systems at once without MIDI.

Erika's relationship with the 606 begins at the level this archive cares about most: learning by living with the object. She identifies it as her first piece of gear and the machine on which she learned drum programming. Interdimensional Transmissions records the next step: BMG gave her a TR-606 in 1997 and invited her into Ectomorph, beginning a continuing hardware-performance practice.

That story explains why a fixed panel can remain useful for decades. The 606 does not ask the player to browse an expanding library. It asks for fluency in seven sounds, one accent lane, pattern memory, track form and the timing relationships created by external instruments. Repetition turns a limitation into a playable vocabulary.

The machine's afterlife divides into preservation, modification and recreation. Original units remain serviceable because their through-hole boards expose clear circuit stages, though battery memory, ageing electrolytics, switches and previous modifications must all be assessed before calibration.

Modification culture added the controls Roland left inside: individual outputs, tuning, decay and direct access to trigger points. These changes can make the machine more flexible, but they also change the relationship between the seven voices and the original mono mix.

Roland later returned the model as the TR-06 Boutique hardware and a software TR-606. Both add conveniences such as swing and expanded sound editing. They preserve the 606 as a named instrument while making clear how specific the 1981 design was: fixed voices, shared accent, straight timing and an output that required the whole kit to negotiate one channel.