DIN Sync is one of those things that I would frequently see listed as a feature in a bunch of different devices—like the Endorphin.es Shuttle Control, a Eurorack MIDI-CV converter module—and nod knowingly as I read the specs. “Ah yes, DIN sync. Of course. Excellent.” But in reality, I didn’t really have a clue what it was. I mean, I knew it was something to do with...clock? It looked like MIDI but...it wasn’t?
To be honest, I felt like when the time came where I needed to truly understand DIN Sync, I would—and suspect that this experience is probably similar for a lot of people.
However, I couldn’t let the mystery lie, and felt like I had to dig into the origins and purpose of this strange protocol—if only to figure out whether or not it was something I should try and find space for in my cluttered and disorganized brain, or dismiss as irrelevant. I simply had to know. Here’s what I’ve learned.
DIN Sync gets its name from the chunky 5-pin DIN connectors that we now most commonly associate with MIDI (let’s not get started on those minijacks). The protocol is comprised of a number of different signals which control functions such as clock, start/stop, reset, and continue, which should be fairly self-explanatory. There are a few others, but not all of them are commonly or even consistently implemented. In its most basic form, different voltages are sent down the individual pins of the DIN Sync cable, which allow devices to synchronize with each other.
[Above: DIN Sync input/output jack on the rear panel of a vintage Roland TR-808.]
To make things that little bit more complicated, DIN Sync is also sometimes referred to as Sync24, or similar variations including Sync48 and Sync96 that were respectively used by different manufacturers such as Korg and Oberheim. The numbers in these names refer to the number of pulses used per quarter note to ensure accurate synchronization. You’ll probably have seen references to 24ppqn before, as it is one of the most common standards. However, if you’ve ever struggled to get devices like Pocket Operators or Korg Volcas to play nicely with other devices via their sync ports, that could well be down to the fact they operate at the somewhat less common rate of 2ppqn—an issue that comes up on Reddit threads and forum posts constantly. Connect a 24ppqn sync signal up to a 2ppqn device for "hilarious" results.
MIDI vs. DIN Sync
The most common solution that we have nowadays to keep modern bits of musical gear in time with each other is—fairly obviously—MIDI, a digital communication protocol designed for communicating fairly large amounts of fairly distinct musical performance information. However, the world of modular synths has in the past decade or so also brought analog clock sync back to the forefront.
[Above: close up of a Roland TR-909's rear panel connections, featuring DIN Sync and MIDI side by side]
DIN Sync sits somewhere in between these two; acting as more than a simple clock, but without all of the bells and whistles of MIDI. And by "bells and whistles," I mean that DIN Sync deals purely in the business of synchronization, and is, in essence, a parallel analog protocol (versus MIDI's serial, digital structure). There’s no CC-like parameter control, and no note data. In other words, you can’t use DIN sync to control the pitch of an instrument like you can with MIDI, nor can you use it to transmit data like the position of a pitch-bend wheel. It's really purely about communicating timing information between multiple connected devices: synchronizing their internal sequencing structures.
Despite sharing a common physical connector, the two protocols are not directly compatible. Do not be tempted to experiment here! In theory, you should be able to use good quality MIDI cables interchangeably with DIN Sync devices, so long as all 5 of the pins are connected internally, but this isn’t guaranteed. [Editor's note: we at Perfect Circuit have had good luck using Hosa MIDI cables for DIN sync; all models seem to have all of the pins wired, so they should work swimmingly.]
If you happen to find yourself in a position where you need to synchronize bits of gear that don’t share a common synchronization standard, there are a variety of dedicated boxes that can provide a solution, including the Kenton D-Sync—which allows you to convert from MIDI to DIN Sync and vice versa—Doepfer’s MSY2 MIDI to DIN Sync Interface—or the very useful Retrokits RK-DINSYNC 3.5mm MIDI to DIN Adapter for the teeny tiny MIDI wonder-box, the RK-006.
So...Why DIN Sync?
Okay so this is all very interesting and all, but what relevance does DIN Sync actually have in 2023? It may well seem like this is just an obsolete technology that has been (or should be) confined to the ages (and there are plenty of sites online that say exactly this). However, modern devices including Squarp’s power-house sequencer Hapax still include support for the standard, as do a variety of others including ALM Busy Circuits Pamela's Pro Workout, Elektron’s Digitone, and the Synthstrom Deluge. But why?!
The answer lies partly in the history of the protocol. None other than Roland themselves created it in the 1980s specifically to allow the synchronization of devices such as the TR-808 (which notably does not support MIDI), the TR-909, TB-303, and TR-606. The significance of these boxes doesn’t need much explanation—and that alone helps outline why support for DIN Sync is still relatively common. The 808 doesn’t seem to be going out of fashion any time soon, and thus DIN Sync will be with us for some time to come.
That said, not everybody owns vintage Roland gear, so it might still not make much sense why the protocol is so prevalent. However, the usefulness of DIN Sync isn’t limited to these pieces of musical legends. MIDI has some well-documented limitations which can interfere with the reliability of the clock in certain scenarios, and its implementation on certain devices can be...idiosyncratic. For these reasons, some folk prefer the simplicity of DIN Sync, lauding its tightness and reliability in the face of MIDI clock's occasional inconsistencies and jitter.
Another modern use for DIN Sync is the possibility to easily interface between a modular system and devices that don’t have dedicated analog clock outputs, but do have dual MIDI/DIN Sync jacks. For example, something like the Elektron Digitakt. In theory, you could use the DIN Sync Output function on the Digitakt in combination with the Din-Sync breakout cable from ALM Busy Circuits as a relatively inexpensive alternative to a MIDI to CV converter if all you need are clock and run signals to pipe into your modular system.
So, Does it Matter for You?
It’s quite possible that you will never need to tangle with DIN Sync. I doubt I’ll be getting my hands on a genuine 909 anytime soon either. However, at least now when it pops up in a menu or listed on a spec sheet, you can be confident that you aren’t missing out.