A Chat with Dr. Hiroshi Akino, the Mind Behind Audio-Technica’s Most Popular Microphones

By January 9, 2019Features, Interviews, Miking

Dr. Hiroshi Akino began work at Audio-Technica 37 years ago, and now keeps his home in their Planning Development Division and R&D Department.

Throughout his career he has worked primarily with microphones, notably designing the AT4033, a condenser mic which has become hugely popular as a home recording staple and studio workhorse. When the mic first hit the market, he was assembling and packaging each and every unit himself.

We sat down with Dr. Akino to chat about his beginnings at A-T, his brief stint with some of Japan’s foremost audio institutions, and what went into designing the AT4033 and AE3300 specifically.

audio technica at4033 AE3300 Dr. Hiroshi Akino

We pick the brain of Dr. Hiroshi Akino, the engineer and designer behind some of Audio-Technica’s most indispensable products.

As one of Audio-Technica’ss longest serving engineers, your work has had a massive influence in shaping their brand identity, as it pertains to microphones. How did you come to be working for their microphone division and what are some of your fondest memories from your time at Audio-Technica?

I joined the company when I was 25 years old after spending my time in Japan Self-Defence Forces as an officer. That was 37 years ago. My first job in Audio-Technica was to operate a production line of the headphones unit. At the time, A-T produced and sold electret condenser headphones but the productivity was very low due to many production failures. My main focus at the time was to improve this production issue.

It was difficult to find the solution within the company so I personally joined the members of Acoustic Society of Japan and The Institute of Electrostatics Japan. In each society, I learnt many things which were not covered by universities.

When I was 29 years old, I left the company and started working in Aiwa.  At the time, professor Mizoguchi who had been in NHK Science & Technology Research Laboratories was working in Aiwa. The reason why I joined Aiwa was to deeply understand his monograph about condenser microphones. After spending my time in Aiwa for two years, I started thinking of developing microphones by myself.

At the same time, my senior from Audio-Technica asked me to come back to the company so I decided to return. This is how I started engineering and development of microphones in A-T.

The fondest memory in this company is that everyone always understood and helped my R&D until today. In addition, I appreciate guidance from professor Mizoguchi and many teachers in Kanagawa Institute of Technology.

The nineties were a period of rapid advancement, not only for A-T, but for audio tech in general. What do you remember about this time and how does it differ from today?

In the nineties, new materials emerged to use for diaphragms which were 2 micrometres of PPS (Polyphenylenesulfide) film and 1.2 micrometres of PEN (Polyethylene naphthalate) film. These materials are used for A-T microphones even now. In terms of circuit parts, smaller FET with a built-in bias diode were getting easier to procure.

These new parts were used for Unipoint series which were developed almost at the same time as 40 series microphones. At the same time, the processing method of Unipoint series diaphragm was applied to 40 series microphones which is known as a wave diaphragm.

The difference from today is in the nineties, A-T was at the early stages of new microphone development so no one had enough knowledge about development and production. So, we had to move on both development of products and production method at the same time. As the result, my overtime hours in a month were more than 150 hours. Nowadays, this level of overtime is considered a problem but it was not special at that time.

The 4033 is credited as being the microphone that brought studio quality condensers to the masses. What were some of the main considerations when designing the 4033? Did it feel like you were working on something special?

The main consideration was to maximise the performance of the microphone with lower cost. The second focus was the production process (parts procurement, assembling, and packing) had to be easy and simple enough to be done by myself.

Regarding the first point, cost was key because AT4033 was originally developed to export and sell in the US market. So I had to design the studio condenser microphone considering low cost structure. One of the ideas was to use a three-dimensional molded diaphragm originally developed for Unipoint series. Besides that, I mounted a baffle to the microphone unit to enhance the driving power of the diaphragm which was not a common design at that time.

During the research and development process, I started from numerical design by calculating the rough design of microphone unit or electric circuit to see the feasibility and the performance capacity. This process had to accompany development of detailed production methods and I continued development of further details of the microphone. In this way, I paid attention not to cause big differences in the performance between prototype and mass production.

At the beginning, I did not expect this product to be sold in high quantity so I designed the product to be simple, so that I could assemble it by myself from the beginning to the end. After launching the product, it was not selling a lot as I expected, so I assembled first few production lots by myself. At the time, one lot was 50pcs and I was assembling, packing, and shipping them out all by myself.

I remember I really enjoyed that time. After a while, more people started helping my job as the product was getting popular in the market. From this fact, I answer to your question, “did it feel like you were working on something special?”, my answer is “Not at all”. After such a period, I appreciate the product has been used by so many people.

I understand that the legendary studio engineer, the late Phil Ramone, also played an important role in the development of the 4033. What was it like having someone of that pedigree on board?

Yes, that was a very valuable for us. It was definitely good for us to get his advice during product development stage.

Were you involved in the design of the AE3300, which uses the same capsule as the 4033a? It seems like another forward-thinking product for artists looking to take their studio work to the live stage.

Yes, I was involved in the development of AE3300. Moreover, I was involved in the most of A-T microphones from the early stage development. From now on, I would like to mention about the engineering backbone of A-T microphones. The basis is the principles taught by professor Miuzoguchi and many teachers in Kanagawa Institute of Technology. I researched the principles until it reached the level of A-T’s original technology and I continued this process many times.

As a result, our technologies regarding transducers including microphones are patented more than 600 times in Japan and about 240 in the US. Perhaps we might have abandoned some of them now. Out of these numbers, 47 patents are still used in A-T microphones.

In this way, I believe our microphones have evolved and been different from other manufacturers.


Find out more about the AT4033 here and the AE3300 here.

Related Posts

Leave a Reply

Related Posts


happy music blog

if you build it

enmore audio

monday records