The Electromotive Laboratories range of loudspeakers were designed from a purely technical brief to achieve a set aim for a set purpose. We do not believe in looking to fill a hole in a market, nor value engineering a product for a preconceived price-point and size. Here at Electromotive Laboratories form always follows function, and price always follows what it cost to make the product. If we can’t make a product fit a price or size without serious compromise we simply will not make that product.
Our aim with our professional monitoring loudspeakers is to deliver an uncompromised result for the purpose the loudspeaker was intended. As users of loudspeakers ourselves we build what we would want from such a product and hope that others will appreciate the same properties we do from our product.
Our acoustics arm builds high end professional recording studios and we often install, commission, and use our own loudspeakers in our own rooms. It is this process over the last 30 years that has led to us developing our current product range in the way we have. We identify any potential issue in the systems and develop working solutions to that issue.
All of our main monitor systems employ our own version of the famous Holland – Newell AX2 axisymmetric horn. This horn was developed at the ISVR – Southampton University, over many years of Dr Keith Holland’s Phd studies as the closest possible form to the perfect high frequency horn. It is not just a simple circular horn, it follows a precise profile that was studied and developed in the laboratories of the ISVR. To this day, to our knowledge, nobody has produced a better horn. The AX2 was specifically designed to be coupled to what is probably the finest 1” throat compression driver ever produced. The AX2 geometry is designed as a perfect continuation of the drive unit throat expansion rate, no change in flare rate or discontinuity is experienced in the propagation of the wave from the phasing plug.
Our smaller series monitors have a newer AX3 asymmetric horn, a precise adaptation of the AX2, again a part of a specially adapted driver to horn geometry match, the AX3 was especially custom manufactured to connect to the chosen drive unit.
The AX2 and AX3 are free from all the issues of distortion and reflection usually associated with compression driver and horn loudspeakers, they do not have a “horn” sound, this was the precise aim of the many years of study at the ISVR. A horn and compression driver is a far superior acoustic transducer to any soft dome loudspeaker.
It is far more difficult to engineer a horn to perform as perfectly as possible, there are so many problems with doing so than just putting a dome in a box, but with the precise and expert engineering we have behind our products we have achieved a level of precision, detail, and distortion free clarity that no dome loudspeaker could ever hope to match.
So many manufacturers have tried to emulate the AX2 since it was first introduced in 1989, some seem to think that just being circular is adequate, but the AX2 is a piece of precise engineering that only achieves the required performance if all aspects of the horn are carefully respected.
AX2 4000Hz In-Wall response
AX2 anechoic beam width
What point all this work in developing the highs if we do not have excellent lows.
In the low frequency range, we have chosen drivers from an extraordinarily large selection of test units. The original AX2 based systems designed by Dr Keith Holland and Philip Newell in the late 1980's were based around the excellent JBL2235 19Hz resonance low frequency driver, a driver now long discontinued. Over the last 10 years at Electromotive Laboratories we have been on a search for a replacement unit. Coupled to the concept of reaching into infrasonic regions yet having excellent transient response and being free from tuning resonances we have finally achieved our goal.
As more modern content has increased demand on loudspeaker systems we were constantly required to look for a more capable loudspeaker in both output and acoustic performance. All our range of loudspeakers use exceptionally capable low frequency drivers coupled with large volume enclosures tuned to work well below driver resonance without stressing the loudspeakers, or losing control of the cone motion. This is not an easy task at all and requires careful application of good acoustic theory.
We do not use any DSP tricks to achieve this, there are no crazy filters, boosts, or limiters, it is all about controlling proper cone motion and careful overlap tuning of the cabinet and drive unit.
Our loudspeaker systems are all designed principally, and recommended for installation in a solid monitor wall. While they will work well in free standing applications, there are so many incurable acoustic issues with this concept that we strongly recommend building a loudspeaker wall where possible. System output is increased by up to 6dB by wall mounting the systems.
As our systems are designed for use in non-environment rooms where the room adds nothing to the low frequency output, they do, therefore, have significant low frequency output that would allow them to be tuned well for free standing use.
Why use compression drivers when most studio monitors use dome transducers?
Quite simply, a dome transducer will never sound as precise as a well implemented compression driver over the same bandwidth.
It is not easy to engineer a compression driver and horn combination that does not sound coloured.
The tendency to use rectangular horns and various forms of pattern control horns in many loudspeakers has led to systems trying to produce unnatural propagation patters and in many ways distorting the propagating wave front. This tendency led to a bad reputation of horn-loaded high frequency systems to sound aggressive, distorted, and resonant. Many horns were badly manufactured and others tried to squash a spherically propagating wave into a ludicrous shape just to achieve some form of pattern control over the coverage of the loudspeaker.
Early design and manufacture of compression drivers left a lot to be desired, as a result of simple ignorance of the science of acoustics, or just simple cost cutting, some examples even had bolts protruding into the acoustic path. Many early and cheap compression drivers had terrible issues with distortion, phase, and amplitude response.
Simply because some people don’t understand the consequences of what they are doing is not reason to dismiss a whole concept.
It is far simpler to engineer an acceptable dome transducer than to engineer a high quality compression transducer, even so, there are some truly terrible dome transducers on the market.
A high-quality compression driver is an instrument of immense precision that requires careful manufacture and design, the result which can be an unparalleled sonic output if done well. The beryllium diaphragm we use in the Electromotive Laboratories Model 5 is manufactured through a process where the metal is vaporised and in a vacuum then deposited upon a copper mould to a precise molecular thickness.
Soft domes on the other hand have many inherent flaws. First of all, inefficiency. Most soft domes when required to deliver high outputs will have the voice coil operating at temperatures that detrimentally affect the balance of the system, when a coil heats up, power compression is encountered and output can fall relative to other drive units in the system leaving an unbalanced sound.
Soft domes themselves have very poor coupling with the air, and poor air loading of the diaphragm which can lead to diaphragm flexing and uncontrollable propagation issues. Some manufacturers have resorted to mini-horns and even acoustic lenses to try to reduce these effects.
Compression drivers on the other hand are immensely more efficient, often over 20dB and thus need only a tiny fraction of the power to drive them, Power compression in studio use is almost non-existent, therefore they remain linear in SPL output up to very high output indeed.
Most compression driver diaphragm assemblies are significantly lighter in weight than a dome radiator of similar bandwidth. The drive unit, horn, and phasing plug put a significantly higher resistive load on the diaphragm further damping diaphragm resonances and break-up. As the whole system is far more efficient (50% compression driver against 5% dome) the diaphragms themselves have to move far less that the equivalent dome loudspeaker.
A well implemented compression driver and horn combination will always be capable of a far better transient response than a well implemented soft dome radiator.
For these reasons, we have long chosen to use compression driver technology. When adequate horns did not exist, we engineered them.
From all of our listening tests our compression driver and horn combinations always exhibit superior transient response and stereo imaging than any soft dome technology we have experienced.
Electromotive Laboratories
A Division of Newell Acoustic Engineering
Funchalinho, Caparica, Portugal
info@electromotive-laboratories.com