The Octagon Philosophy
In professional development or assessment of high-end consumer loudspeakers, much of the same rules and logic applies time after time. Any of such professionals will therefore develop a routine of considered aspects. Some maybe more than others. We should agree on the existence of such routines as something positive, opposite to the idea of just seeking a loudspeaker that simply sounds good. Just think about what a high-end review would look like if a loudspeaker’s performance, or that of any piece of HiFi equipment for that matter, would be described solely by “sounds bad” or “sounds good”, or something in de middle. Quite poor indeed.
Let’s take that thought a step further. It must be important then, that the list of aspects reviewed in such routines fully cover the performance of any given loudspeaker. A list of aspects that covers
both important qualities as well as potential shortcomings. While designing, building and testing exclusive high-end loudspeaker systems for private homes, Aequo Audio developed such a list to work with at all time. It became our philosophy and logo: the Octagon Model.
To excel in every aspect of this Octagon model, some new technologies had to be developed. These technologies are explained extensively by our engineers on the Technology page.
The Octagon Model is also used to explain the qualities of Aequo Audio’s currently available speaker models as presented on our website. Right here on this page, you find the list of universal aspects in the Octagon Model, with a summarized explanation.
The 8 Aspects of the Octagon
1. Size and Form
The first encounter with any loudspeaker would normally be its appearance: its shape, size, look and feel. And of course, size related to performance. Aequo Audio’s design team acknowledge the fact of every line and corner on a speaker being just as important as on a sports car or airplane, and settle only for beautiful products without compromises in performance. Every part of the loudspeaker is designed to avoid indirect sound (late in phase) as much as possible,
as well as diffraction resonances caused by sharp corners.
There is no substitute for deep bass performance. Only by finding new and highly attractive design concepts including state of the art technology, Aequo Audio proves modest size does not always mean lack of dynamic low frequency performance. True full range reproduction unlike ever seen and heard in this size and appearance.
2. Room Acoustics
When explaining the Octagon Model - and listing the eight aspects in it - a frequently asked question is about why there is no response curve (magnitude dB versus frequency) included. Most developers seem to concentrate on a flat response in anechoic laboratory conditions, or acoustic response in well damped ideal environments like studios or fully treated demonstration rooms. This on itself fails to provide for real home performance, in real rooms of different dimensions. It lacks attention for the unlimited variation in the rooms of their customers, including different flooring and furniture.
Aequo Audio uses anechoic measurements and many other response measurements and tests, to develop an understanding of the complex interaction with the room interior. We focus on the result of this interaction, rather than the lab-measured response curve alone. This leads to the implementation of unique adjustment features and dispersion technologies, to finally deliver loudspeakers that will perform very well in virtually any domestic environment. And in those area’s affected most by room acoustics especially: frequency response, and soundstage and imaging (coming up next).
3. Soundstage & Imaging
The involvement of a listener to music recordings highly depends on a realistic reproduction of the musician's and singer's placement. If the recording, live, studio or even electronic production, is done properly, the ability of high fidelity equipment -especially loudspeakers- to set a convincing soundstage, is essential. Aequo Audio carefully studies all aspects involved in this area to aim for lifelike staging, reviewing the height, depth of the stage in comparison to what is known about the
original recording and aim of the producer. The instruments and vocalists should feel real with correct position. Aequo Audio loudspeakers disappear completely while ensuring the experience of holographic imaging. They leave you in good company of a solo singer songwriter, band or full orchestra at the right distance, between the span of the loudspeakers or even far outside.
What is the use of a given loudspeaker that does not reasonably fit the designated space reserved for it in your home? And does a pair of them play just as well in their final position, just as they did at the demonstration you attended? Chances are the performance is seriously compromised if not placed in a very similar and product-specific manner.
Aequo Audio avoids features and technologies that potentially narrow placement possibilities as much as possible. This means no rear firing bass reflex ports bass-booming against the rear wall (or the scuffing of insufficient dimensioned front ports, sometimes even
reveiliing sound effects of poor motor choices on the model’s drivers). It also means no dipole technology in the way this is usually implemented: in a way it only delivers perfect soundstage and imaging when placed meters away from a rear wall.
Instead, Aequo Audio is sure to provide users with an easy, practical and satisfying experience in setup, just as much as the experience of magnificent quality and performance. The addition of technological innovations allows super easy adjustment to virtually any placement in your room, as well as the full range extension into the lowest and highest octaves.
One of the most underestimated qualities of the human ear is to detect impurities in the reproduction of vocals, and even instruments. Only some manufacturers of Hi-Fi equipment already mention the Total Harmonic Distortion (THD) percentage. But this is worth very little without further information on what kind of harmonics are measured, and in what frequency range or at what listening volume.
Aequo Audio uses extended research literature on our hearing organ to determine thresholds in hearing impure harmonics, for each order of harmonic distortion at different listening levels. The ideal balance between warmer sounding even order harmonics and fatiguing un-
even order harmonics are defined for the critical frequency area where the human ear is most sensitive. Strict quality control is needed to avoid any buzzing- or rubbing-sound in drivers, as well as any resonance by the cabinet. Altogether, this understanding then provides production and design rules for all components including the cabinet, as well as their reliability.
The combination of high performance components and built quality fulfills and surpasses the highest standards in cleanliness. The result is life-like, honest and non-fatiguing reproduction of sound, without the addition of any timbre or color.
Another very important aspect of loudspeaker performance is found it its resolution and time behavior. Many design choices in today’s speakers have effects on sound in this area. Bass reflex ports and steep crossover filters will usually have unwanted and audible side effects in the time accuracy of the reproduction: they cause group delay in certain frequency areas. Sudden changes in the time domain will be audible, and so will any group delay surpassing thresholds for a certain frequency domain.
Aequo Audio uses unique technologies that allow full range dynamics without bass reflex ports, while the choice for driver-materials with good self-damping behavior allow shallow low order crossover topology.
When the loudspeaker enclosure and crossover concept is done right, there still remains the pure resolution capability of the drivers. An often heard misconception is that resolution is depending on the weight of the moving parts of a driver. This is important for sensitivity rather than resolution as it can be compensated by amplifier power. Aequo Audio implements driver motors with magnet and voice coil designs that have the fastest signal response, and with clean dynamic capabilities in lower extended frequencies.
Made possible by Aequo Audio loudspeakers with true time-accurate performance and incredible resolution in every frequency area, you will hear the difference in excellence straight away, and discover new details and qualities in your music collection.
7. Amplifier Matching
One should always be careful buying speakers to be used with a certain amplifier. Especially, if the amplifier is limited in power capabilities, damping factor, and how it copes with low impedances at steep phase angles.
Aequo Audio provides most loudspeaker designs with a speaker-integrated high power amplifier for the active (sub) bass section to relieve the amplifier from subwoofer duty. Far less power is needed to drive only the mid-bass and high frequency section, and lack of damping by the amplifier will be less
audible. The 8 ohms nominal passive section is easy to drive with no painful impedance dips at steep phase angles. The sensitivity is very high for a loudspeaker of its size, as well as its dynamic capabilities, allowing a wide range of power ratings for easy amplifier matching.
Almost any amplifier is very well suited for your Aequo Audio loudspeakers. You can match the resolution, natural reproduction, and non-fatiguing sound of the loudspeakers with any amplifier you like, bringing the characteristics of the amplifier to life.
Some systems only seem to play well at low or high levels. Some smaller systems don’t even allow live listening volumes. Much of these flaws can be found in behavior of the drivers: their size and the way they have to work together in each driver's frequency band together with their specific excursion limitations.
Aequo Audio fits the most capable drivers in very modest size cabinets: (sub)woofers and tweeters with high sensitivity and excellent thermal and excursion properties. Both the drivers and their work-
place surroundings are designed to avoid compression and distortion at higher excursions, even when used in lower than normal frequencies.
Smart interpretation of the complex interaction by the highly capable full range hardware with a real-world room, allow pure pleasure and deep emotion to happen at the lowest and highest listening levels. You will hear the full dynamic bursts in your favorite recordings as they were meant to be.