Graham Audio develops high-end passive loudspeakers for landmark London venue

23rd March, 2015

The Royal Opera House in Covent Garden was one of the first professional users of the Graham Audio LS5/9 loudspeaker system. Some months later, they came back to Paul Graham with a simple request: "could you make something equally as good, but louder?".

"Sure, how loud?" was the reply. At this point the full scale of this project was realised - they wanted to replace their front-of-house loudspeaker system!

The existing system had worked reliably for 15 years, but it was a complex 5 way active system. Simplification was a key requirement, but the quality had to be maintained. With advances in drive unit technology, and with Derek Hughes at the drawing board, could Graham Audio produce a totally passive design that sounded at least as good as the existing system, and preferrably as good as the new LS5/9?

It's fair to say that this was something of a challenge for Derek. Was it possible to translate all of his experience with neutral and life-like high-end domestic audio into the high-SPL public address domain without sacrificing quality?

Naturally, Volt were immediately brought on board. As well as high-end hi-fi applications, their drive units are used in many quality PA and high-level studio monitors, and they had several potential solutions ready and waiting. Derek started with their most promising midrange unit, and so began a long process of refinement, resulting in a highly developed version of this massively over-engineered 3" midrange dome that possesses all of the required articulation and subtlety, while boasting an extremely high power handling.

Coupled with no fewer than three 10" mid-bass and bass drive units, a high power 34mm soft-dome tweeter from SEAS, plus an absolutely massive crossover network, SYSTEM 3D was born. Standing nearly 6 feet tall, it was designed to be driven by a 1kW amplifier to expremely high sound power levels, while having the classic BBC-influenced openness and neutrality, this system is suitable for use in many applications including studio monitoring and domestic hi-fi in large listening rooms.

The first prototype was taken to trial at The Royal Opera House, and Alan Sircom was invited along to see how the project was progressing. Read more at the Hi-Fi+ website...