Five minutes with Nathan Bentall from Radix 2

Like all good tech entrepreneurs Nathan Bentall started his company – Radix 2 Limited – in a garden shed. Fresh out of Sony’s pro-audio lab in 2006, Nathan started the business as a design consultancy but over the past decade, Radix 2 has been continuously expanding its reach, and now provides full design services for electronic products, including circuit design, PCB layout embedded and PC software, design for CE/FCC (certification or compliance schemes, to you and me). As Nathan is an audio enthusiast, – and one time chair of the Audio Engineering Society UK – usually there’s some audio involved, but it’s not mandatory! And the name Radix 2? Well it’s a pun for those in the know, Nathan tells me – Radix means ‘root’ or ‘base’, so it kind-of means base-2, aka binary – the system of numeration used by computers. Get it?

The team at Radix 2 has designed the electronics and software for some exciting products over the past few years. There’s a neat little speaker that you can attach to a mobile phone and, at the other end of the audio spectrum, they’ve designed the electronic circuitry for a very specialist headphone amplifier for UK audio transducer innovator, Warwick Audio. This is the new generation of headphones: instead of using magnetic fields to move air, as would be the case with a conventional transducer, the Radix 2 amplifier supplies high voltages to generate electrostatic fields, which apply force to an super-light diaphragm. The upshot is a headphone/speaker that generates very little distortion or resonance, giving an ultra-high quality sound. As well as amplifying and driving the headphones, the amplifier also functions as a very-high-quality USB audio 2.0 sound device. You won’t be buying them for everyone for Christmas though as they are definitely a top-end product (current UK price is £ 4,594.99 per amplifier and headphone set!).

Since then Radix 2 has taken the design for the electrostatic amplifier and condensed it to fit into a self-contained headphone that is completely wireless and connects via Bluetooth  Nathan says, “I believe we made the world’s first self-contained, self-powered full-electrostatic, Bluetooth headphones – with much of the technology we’re developing, we’re pushing the boundaries of high performance and miniaturisation – mixing high voltage, radio and best quality audio circuits whilst also achieving all requisite regulatory and safety compliance. This is definitely one of our most challenging projects”. The headphones have been shown at the Consumer Electronics Show (CES) in Vegas 2017.

Nathan is also excited about Radix 2’s work on an acoustic and optical device for Aedio Inc., a Boston-based medical start-up. Connected to your smartphone/tablet and monitoring your breathing and pulse, it can help those with long-term conditions, such as asthma, manage their condition. Nathan calls it “The next stage in personal health monitoring, but going beyond the Fitbit curiosity of pulse and general activity, the sensor and software will provide potentially life-altering data to help people manage their real health issues”. In the first application the device will provide an early-warning system for asthma attacks. Clinical trials are presently at the ethics-review stage.

And, for all those bat enthusiasts and conservationists, Radix 2 has developed bat detectors too! Batbox (Griffin and Baton XD) detectors digitally process the ultrasonic calls of bats to shift them into the audible range, enabling species identification and discernment of various behavioural patterns without ever setting eyes on these elusive creatures of the night. “This was a product where we not only designed all the electronics, software and DSP algorithms, but also managed the mass production, supplying completed assemblies in quantity to be badged and sold by the customer.

Nathan says locating at OCFI has lots of benefits for Radix 2. They have good ties with Hackspace in the basement, enjoy the flexibility of the office space provided and the Launchpad events. The Oxford location is a plus too with the buzz around new business growth and a pool of local experts that they can pull in for particular projects. Challenges for 2017? Nathan says “I’m really proud of what we achieved in the two years we’ve been in the centre – we’ve worked with some amazing companies and had the opportunity to develop exciting, innovative technology and in a great environment. For 2017, I hope we can continue to grow – I’m looking forward to further work with our existing customers, and also taking on new challenges – the only thing we love more than facing a new technical challenge, is delivering a solution.

We hope they don’t outgrow OCFI too soon.

Check out Radix 2’s website here.