Analogue Circuit Behaviour (ACB) is the technology behind the authentic sound and responsive behaviour of Roland’s new range of AIRA products. It faithfully captures the sound and feel of some their most revered classics, using original design specs, consultation with original engineers, and a detailed, part-by-part analysis of each analogue circuit in our own pristine units.

Analogue electronic musical instruments consist of various analogue components including resistors, capacitors, and transistors. The unique sound of analogue instruments is due to the distinctive characteristics of the individual analogue components. So-called “vintage” instruments, in particular, show extremely distinctive sound and behaviour due to the variable instability of the electronic components.

Rhythm machines and synthesizers such as the TR-808, TR-909, TB-303, and SH-101 enjoy entrenched popularity to this very day even though they first appeared over 30 years ago. This is because musicians across the globe have recognized their unique sound and used them to forge entirely new genres of electronic music.

To produce the new AIRA products, Roland aimed to pick up where these analogue classics left off and to develop a completely new technology which models the traditional analogue circuits, right down to their behavioural levels.

ACB is drastically different from conventional methods of modelling, and reproduces each analogue component by thoroughly analysing each detail of the original design drawings. By combining the analysed components in exactly the same manner as the original analogue components, detailed characteristics of the original musical instruments emerge and can be reproduced completely.

This analysis requires knowledge of the design and development processes of the original analogue instruments. It is not possible to reproduce the original sounds just by logically analysing the analogue circuits. This is because the original engineers used a design approach which maximized the capabilities of the analogue components. Throughout the development of ACB, Roland cooperated with the original engineers who designed and developed these iconic instruments. With their expertise, they could ensure that they fully reproduced the ideal state of their creations.

Utilizing the enormous calculation power of state-of-the-art DSP, ACB not only precisely emulates the analogue-specific characteristics of Roland’s classic gear, but also delves into areas the original engineers tried to go but ultimately abandoned.