Loudspeaker Design
39 years of extensive listening to a very wide variety of audio systems and rooms has given us the confidence to design and voice speakers, by ear, to satisfy the most relevant test, the listeners pleasure.
THE AYAL
Since the launch of our first loudspeaker, the Translator in March 2016, we have wanted to fully explore the area of time coherence in our designs and the benefits it should bring to music listening.
We already know the importance in using 1st order crossover filters because they establish time and phase coherence for each drive unit and for all frequencies. Our crossovers are also transient perfect in operation and this qualifies our loudspeakers as prime candidates for physical driver alignment on the baffle.
Loudspeakers that use 2nd, 3rd or 4th order crossovers will have less benefit from moving the tweeter backwards, as the signal passing to them already has frequency dependent time errors.
Work began on the Ayal in June 2017 and in the prototype we seated the tweeter in a movable compartment positioned above the bass driver, allowing us to experiment with tweeter alignment.
Prior to moving the tweeters we needed every other element of the design to be in place and the Ayal performing to its absolute best. Having achieved this it was time to start the process of aligning the tweeter.
It was interesting to hear no noticeable change when the tweeter was at the extreme front or moved too far rearwards but eventually there became a distinct hot spot, a 10mm window, that narrowed to 5mm once the listener had acclimatised to the structure of improvements that were appearing.
It was very exciting to hear what at first seemed subtle and nuanced become magnified with extended listening.
What were we hearing?
Initially we picked up an extra tight focus on percussion instruments, their energy concentrated within each sound and preceded by the smallest of details on the leading edge.
Over extended listening there developed the feeling of people performing 'live' rather than being reproduced from a recording. Each part of the music became more distinct and separate yet it let the listener easily accept this separation and make it gel as a greater unified performance.
A voice was often placed so vividly you could imagine seeing the singer at the microphone in front of you.
At the very end of optimising the tweeter position we began to wonder if the pitch of playback had been effected. It just sounded like the increased differentiation of instruments was due to the pitch of each now being resolved with greater accuracy.
We feel the Ayal is a very special loudspeaker, presenting music as a live event.
THE TRANSLATOR
It has been an absolute pleasure to design the Translator.
A speaker to enhance the emotions of the most critical music listener.
Having worked in the hi fi industry for 36 years, regularly auditioning and demonstrating well known and respected speaker brands, it was surprising that only a handful of them performed well enough to present music as naturally and realistically as one would wish.
Having such a long period of years listening to countless speaker design variants (electrostatic, full range single driver, open baffle, Omni-directional, horn) you become experienced in hearing the strengths and weaknesses inherent in each approach and gradually you start to form a definite view of the areas in sound reproduction that seems to provide the most musical performance.
This I feel was a very strong point for us. It was never going to be a question of producing a speaker and just seeing how good we could get it to perform. We already knew the areas of importance to us and how we expected The Translator to present the music.
When listening to music it needs to be effortless, natural and easy, allowing you, the listener, to relax into great detail presented in a well focussed and solid soundstage where vocals and instruments are free of colouration and maintain their natural timbre. The smallest transients must be retrieved to help maintain the freshness and speed of response while never sounding harsh or aggressive.
The bass should have sufficient extension to work well in various room configurations with tight control, even output and low colouration.
Our experience also included many years of listening to a design of speaker that used a 1st order crossover filter instead of the usual 2nd, 3rd and especially 4th order circuits found in many high-end designs. This speaker with 1st order crossovers had really become a reference point for us because it would continually out-perform all others by sounding more natural and realistic. We came to appreciate over the years that the crossover was responsible for its advantage over the others, even those speakers with considerably better drive units and enclosures.
It was a very exciting prospect to think that we could develop a design of speaker using a 1st order crossover and upgraded drive units mounted in a heavy, rigid enclosure and then paying close attention to the components in the crossover, implementing higher quality inductors and capacitors of much closer tolerances.
The field of speaker design is a fascinating arena of so many differing opinions and strategies. You may be the humble hobbyist or the maths and physics academic. It doesn't matter. It really is open to all abilities.
The internet provides a wealth of information regarding crossover circuits and the pros and cons of 1st, 2nd, 3rd, & 4th order. Reviews, forums and interviews with manufacturers proved very informative for our understanding the advantages of 1st order and why it is rarely implemented.
Here are its unique properties :
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Passes through all signals with the same time delay.
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Produces a phase difference that is constant at all frequencies.
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Maintains amplitude and phase, unchanged, thus being transient perfect.
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Has the slowest electrical roll-off, -6dB per octave.
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Has the fewest reactive components, 1 inductor and 1 capacitor.
The apparent disadvantage is the -6dB electrical roll off not easily translating into an actual acoustic -6dB per octave roll off, but if achieved, each driver would then operate/overlap too close at the crossover point creating many issues for the listener. Power handling may also be compromised.
This one disadvantage discourages the vast majority of manufacturers.
If your speaker design priority is amplitude, a flat frequency response, 1st order is going to struggle to give you that without compromising sound quality.
Your hearing characteristics are, however, amplifying the midrange frequencies already and this is where you can now implement a 1st order crossover optimised, not for amplitude, but simply for what your hearing is telling you sounds right and natural. The resulting crossover design also minimises driver overlap and restores power handling.
Alternatively if you have access to speaker design software and input the relevant data of the drive units, enclosure and crossover circuit you plan to use the software will produce graphs and plots that show your 'theoretical' speakers frequency response, power response, transfer function, phase and impedance, et cetera. This pictorial information is fascinating and beguiling but moves your focus into trying to achieve the best 'measured' loudspeaker and not necessarily the best 'acoustic' loudspeaker. The whole design process simply becomes dominated in satisfying the goal of 'amplitude', the flat frequency response, and that's when your design software will lead you away from 1st order, and your music is about to have time coherence and phase coherence removed.
First Order Crossovers
We use 1st order crossover filters for the tweeter and woofer drive units in our speakers. We do this because the music reproduced appears very natural, easy to listen to and understand with effortless detail and a realistic timbre coupled to solid imaging of the sound stage.
At 3 Square Audio we are very experienced listeners of music playback systems (39 years and still going strong) and we definitely know how we want our speakers to replay music but only slowly are we beginning to understand why 1st order gives us ALL the properties we want. It is a crossover that can help the speaker drive units, more than any other, work as a team.