AES Europe 2025

UWB as a RF protocol is being heavily used by handset manufacturers for device location applications. As a transport option, UWB offers tremendous possibilities for Professional audio use cases which also require low latency for real time requirements. These applications include digital wireless microphones and In Ear Monitors (IEM’s). These UWB enabled devices, when used for live performances, can deliver a total latency which is able to service Mic to Front of House Mixer and back to the performers IEM’s without a noticeable delay.

UWB is progressing as an audio standard within the AES and it's first iteration was in live performance applications. Issues relating to body blocking due to frequencies (6.5 / 8GHz) and also clocking challenges that could result in dropped packets have been addressed to ensure a stable, reliable link. This workshop will outline how UWB is capable of delivering a low latency link and providing up to 10MHz of data throughput for Hi Res (24/96) Linear PCM audio.

The progression of UWB for Audio is seeing the launch of high end devices which are being supported by several RF wireless vendors. This workshop will dive into the options open to device manufacturer who are considering UWB for their next generation product roadmaps.

Digital filters are often used to model or equalize acoustic or electroacoustic transfer functions. Applications include headphone, loudspeaker, and room equalization, or modeling the radiation of musical instruments for sound synthesis. As the final judge of quality is the human ear, filter design should take into account the quasi-logarithmic frequency resolution of the auditory system. This tutorial presents various approaches for achieving this goal, including warped FIR and IIR, Kautz, and fixed-pole parallel filters, and discusses their differences and
similarities. Examples will include loudspeaker and room equalization applications, and the equalization of a spherical loudspeaker array. The effect of quantization noise arising in real-world applications will also be considered.

Tutorial: Capturing Your Prosumers
This session breaks down how top brands like Samsung, Apple, and Slack engage professional and semi-professional buyers. Attendees will gain concrete strategies and psychological insights they can use to boost customer retention and revenue.

Format: 1-Hour Session
Key Takeaways:
- Understand the psychology behind purchasing decisions of prosumers, drawing on our access to insights from over 300 million global buyers
- Explore proven strategies to increase engagement and revenue
- Gain actionable frameworks for immediate implementation

Extensive studies have been made into achieving generally enjoyable sound colour in headphone listening, but few publications have been written focusing on the demanding requirements of a single audio professional, and what they actually hear.

However, headphones provide fundamentally different listening conditions, compared to our professional, in-room monitoring standards. With headphones, there is even no direct connection between measured frequency response and what a given user hears.

Media professionals from a variety of fields need awareness of such differences, and to take them into account in content production and quality control.

The paper details a recently published method and systematic steps to get to know yourself as a headphone listener. It also summarises new studies of basic listening requirements in headphone monitoring; and it explains why, even if the consumer is listening on headphones, in-room monitoring is generally the better and more relevant common denominator to base production on. The following topics and dimensions are compared across in-room and headphone monitoring: Audio format, listening level, frequency response, auditory envelopment, localisation, speech intelligibility and low frequency sensation.

New, universal headphone monitoring standards are required, before such devices may be used with a reliability and a confidence comparable to in-room monitoring adhering to, for example, ITU-R BS.1116, BS.775 and BS.2051.

Since we've moved from stereo to surround and 3D/immersive productions, many immersive music mixes still sound very much like larger stereo versions. Part of the reason for this is the record company's demands and the argument, that people don't have properly set up systems at home or only listen with headphones. But that's not the way to experience the real adventure, which is to create new, stunning sound and musical experiences. The workshop will not criticize mixes, but try to open the door to the new dimension of music and discuss the pros and cons that producers have to deal with today.

Time selective techniques that enable measurements of the free field response of a loudspeaker to be performed without the need for an anechoic chamber are presented. The low frequency resolution dependent room size limitations of both time selective measurements and anechoic chambers are discussed. Techniques combining signal processing and appropriate test methods are presented enabling measurements of the complex free field response of a loudspeaker to be performed throughout the entire audio frequency range without an anechoic chamber. Measurement technique for both nar field and time selective far field measurements are detailed. The results in both the time and frequency domain are available and ancilliary functions derived from these results are easily calculated automatically. A review of the current state of the art is also presented.

This tutorial is based on a Journal of the Audio Engineering Society review paper being submitted.

2025 marks the centennial of the commercial introduction of the modern dynamic direct radiating loudspeaker, Radiola 104, and the publication of Kellogg and Rice’s paper describing its design. The tutorial outlines the developments leading to the first dynamic loudspeakers and their subsequent evolution. The presentation focuses on direct radiating loudspeakers, although the parallel development of horn technology is acknowledged.

The roots of the dynamic loudspeaker trace back to the moving coil linear actuator patented by Werner Siemens in 1877. The first audio-related application was Sir Joseph Lodge’s 1896 mechanical telephone signal amplifier, or “repeater.” The first moving coil loudspeaker was the Magnavox by Peter Jensen in 1915, but the diaphragm assembly resembled earlier electromagnetic loudspeakers. The Blatthaller loudspeakers by Schottky and Gerlach in 1920’s are another example of a different early use of the dynamic concept.

It is interesting to take a look at the success factors of the dynamic loudspeakers, creating a market for quality sound reproduction and practically replacing the earlier electromagnetic designs by the end of 1920s. The first dynamic loudspeakers were heavy, expensive, and inefficient, but the sound quality could not be matched by any other technology available then. The direct radiating dynamic loudspeaker is also one of the most scalable technologies in engineering, both in terms of size and production volume. The dynamic loudspeaker is also quite friendly in terms of operating voltage and current, and what is important, the sound can be adjusted through enclosure design.

The breadth of the applications of dynamic loudspeakers would not have been possible without the developments in magnet materials. Early dynamic loudspeakers used electromagnets for air gap flux, requiring constant high power (e.g., Radiola 104’s field coil consumed 8W, while peak audio power was about 1W). Some manufacturers attempted steel permanent magnets, but these were bulky. A major breakthrough came with AlNiCo (Aluminum-Nickel-Cobalt) magnets, first developed in Japan in the 1930s and commercialized in the U.S. during World War II. AlNiCo enabled smaller, lighter, and more efficient designs. However, a cobalt supply crisis in 1970 led to the widespread adoption of ferrite (ceramic) magnets, which were heavier but cost-effective. The next advancement especially in small drivers were rare earth magnets introduced in the early 1980s. However, a neodymium supply crisis in the 2000s led to a partial return to ferrite magnets.

One of the focus points of the industry’s attention has been the cone and surround materials for the loudspeaker. Already the first units employed relatively lossy cardboard type material. Although plastic and foam materials were attempted in loudspeakers from 1950’s onwards, plastic cones for larger loudspeakers were successfully launched only in the late 1970’s. Metal cones, honeycomb diaphragms, and use of coatings to improve the stiffness have all brought more variety to the loudspeaker market, enabled by the significant improvement of numerical loudspeaker modelling and measurement methods, also starting their practical use during 1970’s.

A detail that was somewhat different in the first loudspeakers as compared to modern designs was the centering mechanism. The Radiola centering mechanism was complex, and soon simpler flat supports (giving the name “spider”) were developed. The modern concentrically corrugated centering system was developed in the early 1930’s by Walter Vollman at the German Gravor loudspeaker company, and this design has remained the standard solution with little variation.

The limitations of the high frequency reproduction of the early drivers led to improvements in driver design. The high frequency performance of the cone drivers was improved by introducing lossy or compliant areas that attempted to restrict the radiation of high frequencies to the apex part of the cone, and adding a double cone. The introduction of FM radio and improved records led to the need to develop loudspeakers with more extended treble reproduction. The first separate tweeter units were horn loudspeakers, and the first direct radiating tweeters were scaled down cone drivers, but late 1950’s saw the introduction of modern tweeters where the voice coil was outside the radiating diaphragm.

The latest paradigm shift in dynamic loudspeakers is the microspeaker, ubiquitous in portable devices. By manufacturing numbers, microspeakers are the largest class of dynamic loudspeakers, presenting unique structural, engineering, and manufacturing challenges. Their rapid evolution from the 1980s onwards includes the introduction of rare earth magnets, diaphragm forming improvements, and a departure from the cylindrical form factor of traditional loudspeakers. The next phase in loudspeaker miniaturization is emerging, with the first MEMS-based dynamic microspeakers now entering the market.