In mid 2016, Periodic Audio Inc. was born. The vision was to make affordable, high performance IEMs that just worked. Not glitzy, just straight-ahead engineering. A line was created, and released to great applause. However - there was a growing call for detachable cables.

In response to that call, we looked at the options on the market, and realized they were pretty bleak. Lots of companies offered their own 2 pin solution, usually a rectangular plug with a pair of pins, that plugged into a rectangular socket with a pair of contacts. Of course, polarity is an issue - get it backwards and the sound is terrible. So there usually was a “large” key to enforce polarity, but given the size of the connector, they’re not that big in the first place and can be jammed in incorrectly. And those pins are quite small and delicate too, and bending one just a bit means when you’re plugging it in, you could bend it over all the way and break the pin off.

Not to mention, you had to choose from about 30 different models/styles, that were all incompatible. Even if from the same vendor.

Then there was the nearly-ubiquitous MMCX. Now, we’re engineers with deep experience in lots of fields. And we’ve used thousands of MMCX connectors over the years (and that resulted in hundreds of millions shipping in products). They’re great RF connectors - but that’s what they are, RF connectors. They’re not designed for hundreds of mate/unmate cycles. They’re not designed for hundreds (or, in some cases, dozens) of rotations. They’re attached once, the cable is positioned and glued down, and that’s it. And often, male and female components from different vendors were not compatible.


So we scratched the MMCX off the list. Yes, it’s attractive because it’s small. And it solves the issue of polarity. But they’re extremely expensive, delicate, not designed for lots of plugging/unplugging, not designed for rotating, and are not really suitable for both sides to be “cable/panel mounted” in terms of soldering. In other words, they are small - but for every other feature, they are not suitable for use as an IEM connector.

So, left with a total of zero options, we set about making our own. We weren’t going to settle and punt and accept what everyone else did. Rather, we’d make our own solution. And then we’d open-source the design and supply chain so everyone can use it, gratis. Why not? It’s what the industry needed - we were sure we’re not alone in our frustration of existing options.

So in late 2019, we started with a clean sheet. For starters, why just 2 connectors? Yeah, that’s all you need for a speaker - but IEMs are now more than just speakers, aren’t they? Maybe you want a mic in your unit, or a digital sensor? Let’s make it 3 connectors - one defined as the speaker positive, one defined as ground, and one as an acccessory that can be used however the manufacturer decided. Suddenly more than just a “speaker on a cable” became an option.

It should also be polarity-proof. You can insert it 100% of the time with perfect polarity.

It needed to be rugged - able to handle 2500 insertions, and 10,000 rotations.

It needed to be tiny - small enough to fit on a sub-5mm diameter neck, with less than 10mm of total jack depth.

And it needed to be low cost. A connector that costs $15 does no one any good.

So we started the process. Our model? That 100+ year old design, the phono plug. We’d do a TRS plug and jack - that’s 3 contacts, fully defined in space, and polarity-proof - you can’t plug it in wrong. And consumers are really, really used to seeing this form factor. It’s intuitive what to do with it.

Next, we needed size. Lots of engineering went into it, and a dozen mechanical models were machined up. We strength-tested various diameters and lengths of the plug, and settled on a 1.8mm diameter, 8mm long plug. It’s half the diameter of the 3.5mm connector you’re totally familiar with, but only 1/3rd the length. That allowed us to shrink the length of the jack down to 10mm.

We began searching for manufacturing partners in 2020, and settled on XXX. Tooling fees were paid, samples made and tested, and finally approved. The result is what you see here - IDEEL. A purpose-designed connector for IEMs.

What do we get for all this work, for paying the high 5 figures for design and tooling? Nothing tangible. But we do get the satisfaction of knowing that we did something good for the industry, and by open-sourcing the design and the manufacturing chain of this design, we’re giving back to the community that allowed us to flourish.