About ESI


ESI Audiotechnik GmbH is located in Leonberg, a nice town located close to Stuttgart in the south of Germany. In this region, everything is about engineering with an interesting mix of small and mid sized as well as large companies that are the innovation leaders in their field. Global players in the automotive industry, leading manufacturers for machinery and tools and the European headquarters of international IT companies are all located around here. Locals here have been busy with clever engineering and the innovative design of new products and technology for a very long time.

While many especially around here also inside our company might argue that such engineering work is important, it is also common sense that there should be something as a balance beyond work for everyone: for us, that is music - our priority, our passion.

It is no surprise that everyone at ESI combines this love for music and the passion for it with the job - it is the essence of what we are doing. Experience combined with the understanding of the needs of our customers is the driving force behind our product development. We have years of experience in professional audio as musicians and sound engineers, some as ambitious hobbyists and others as professionals. We have keyboard players, guitarists, drummers and singers in our team. Some of us are synthesizer enthusiasts with deep knowledge and experience, others have worked as professional sound designers as well as in movie post production.

We know what our customers expect from our products, because we use them as well!

The history of ESI goes back to RIDI multimedia GmbH, a company that was originally setup in 1998 to provide software development and consulting services for the audio industry and additionally ended up becoming a distributor for selected professional audio hardware and software products in Germany. Claus Riethmüller, the founder of RIDI multmedia GmbH, decided to turn his sound design hobby, his passion for music and his skills as a software engineer into a business that was started from his bedroom studio - it just seemed to be more fun compared to continuing with the development of database systems.

Some time after that, the first ESI products have been developed in Korea by a company called Ego Systems, Inc. (which is where the ESI name originally comes from) and in 2006, ESI Audiotechnik GmbH was setup as the result of the already existing strong partnership with the idea to improve ESI products and make them more popular. The term 'Audiotechnik', which stands for 'audio technology', was choosen, to show that fundamentally it is the innovative technology that makes a product design unique and valuable. After a transition period, ESI Audiotechnik GmbH aquired all the Korean product designs in 2010 and become fully responsible for the development and the full engineering work for all ESI products. Ultimately RIDI multimedia GmbH was merged into ESI Audiotechnik GmbH in 2013 and now all the product development is handled at our headquarters in Leonberg, which lead to our slogan German Design. Performing Worldwide.

Product development at ESI is always based on the idea of providing a very cost effective solution with an exceptional value for money. We do not have an overblown marketing budget that you pay for and we do not invest into writing stories that describe basic common functionality as something unique by twisting words. We focus on functionality and features, often adding something unique compared to others. This makes it possible that ESI solutions are not only affordable, but due to their set of features have become especially popular in the world of home recording and for professionals that need to operate on a budget.

ESI products are used in many professional and semi-professional music studios and have become a preferred choice by musicians and DJs around the globe. By mid 2018 we have been making audio products for twenty years and it is no surprise that we have since become one of the leading vendors for audio equipment - to the extend that our engineering team has been involved in the design and development of many products for other famous players in the industry. The ESI branded as well as various OEM products and other designs from ESI Audiotechnik GmbH are well known and used daily by hundreds of thousands of customers everywhere in the world. If you are a musician, a DJ or a producer, the chances that you are or have been using a product our engineering team has been involved in, are very high.

Today ESI products are manufactured by our key partner, the largest electronic musical instrument factory in the world with one of the best quality control systems within the industry.

Key Technologies


When you look at our products, you will find several items that are unique and a bit different. For instance, with our MAYA44 eX, we are the only vendor worldwide that offers an affordable and yet very professional PCIe audio interface. It is impossible to find any other device on the market with this price point and such excellent performance when it comes to low system load and ultra low latency. So it is not a surprise that many customers in special industries use this card as a solution in meassurement systems or for quality control or simply in industrial applications where higher performance and stability is the most basic requirement. Other unique solutions include products like our GIGAPORT HD+, which now in the 4th generation provides a high end, yet extremely compact, solution for multichannel playback. You won't find any other comparable product at this size that focuses so much on pristine multichannel sound delivery.

We are one of very few vendors of audio interfaces that develop the driver software by ourselves. By avoiding generic drivers from third parties, we are in full control not only of performance, but also features and functionality. Our Windows drivers are known for their stable low latency operation, something often confirmed by user reviews and by the press. This is based on our own special driver technology, EWDM - an enhanced version of the Microsoft WDM driver standard. Our EWDM drivers provide a perfect integration of all important driver standards, incl. ASIO 2.0, MME, WDM and DirectSound. All these can be used simultaneously both in multichannel and in stereo operation. This ensures that our audio interfaces through their drivers are compatible with virtually any audio application, not only professional music software, but also consumer audio application and legacy software (also multichannel) that was originally designed for older Windows versions. This functionality with ASIO and WDM (and Kernel Streaming) is provided with ultra low latency and adjustable settings based on system performance. The support of exclusive mode ensures that audio signals are sent out non-altered, without any changes in quality, 1:1 through out the device - a function that is not only important for devices with digital outputs, but also to provide the best audiophile quality driving the DA converters on the hardware.

With the support of our DirectWIRE technology, we also add the functionality to route audio signals inside your system back into other applications. What can be described as a virtual digital cable makes it possible to transfer signals from any application, no matter if it us using ASIO, MME, WDM or DirectSound, into another one, also supporting all driver models - in just stereo or for multiple channels. The new DirectWIRE output routing for our multichannel devices makes it possible to switch and swap output channel assignments in realtime and on the fly, even while audio applications are running. Such functionality is not provided by any other audio interface vendor.

Speaking of drivers, although a totally different type: for our active studio monitor speakers, we develop our own speaker drivers. Instead of using standard components, we design the speaker drivers down to the chassis, the coil, the cone and all other parts. This makes it possible to provide better sound quality without the usage of additional any circuitry in the electronics that needs to fix the shortcomings or tune a speaker driver. Also it allows us to be more innovative: ESI has been the first vendor to offer a 5" active studio monitor targeted for bedroom studios, essentially creating a whole product category. Later we were the first vendor to use Kevlar as cone material for this type of active monitors - something that has since become very popular within the whole industry. And more recently, our uniK 05+ and uniK 08+ add unique and clever functionality for an active studio monitor such as the special character tilt EQ, the ESI bass port plug and the possibility to adjust the front and back independently with the included decoupling rubber feet.

Another important technology is based on our commitment to MIDI. While many vendors seem to move away from making computer MIDI hardware, we came up with new designs such as the worlds first MIDI interface with automatic input / output detection (currently available as USB cable with MIDIMATE eX). Ultimately that technology resulted in our M8U eX, a professional high performance USB 3.0 MIDI interface with extremely tight timing and a total of 16 ports that can each be used as an input or an output.



ESI products are sold worldwide through a network of dedicated distribution companies. If you are looking for a local reseller or if you want to get information about our products locally or in your local language, please contact one of our distributors.