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Coming soon: Orpheus Apollo 'Signature' Loudspeakers


with new "CCD" Crossover Technology

Fully Factory Sanctioned by Brad Serhan & Orpheus Loudspeakers

Apollo "Signature" Loudspeakers

Upgrade AUD $990.00

The original Orpheus Apollo Loudspeaker is now nearly discontinued (early January 2014) after 700 pairs were made. For unusual reasons, the drivers used in the Apollo were of an order of greater quality for a Loudspeaker that sold for AUD $1999 - and now that quality can be untapped, but at an additional cost that could not have been applied for a speaker selling for two thousand dollars in a very tight market. This is an unusual opportunity.

You will need to secure a pair first - we will try help you when able.

How does the performance compare when fully upgraded? Like an astonishing speaker at virtually any price. The 7" Midrange/Bass driver would not be out of place in speakers costing tens of thousands of dollars. The Silk Dome Tweeter is the latest in modern design that is a trend towards lager domes and large roll-surround that also doubles as ring radiator and large double-chamber with the lowest Fs resonance we have seen, period.

The upgrade features new internal silver-clad solid core copper wire and the crossover is the latest in terms off research into speaker behaviour that suppresses jitter effects, in fact the more correct term for jitter is phase noise.

"CCD" Crossover refers to Clean Current Drive technology - a new approach to Crossovers, indeed a new type of Crossover that has been developed over the last 3-4 years.

For a long time it has been known, but largely ignored, that it is the current through the Voice Coil rather than the voltage across the Voice Coil, that makes a cone move. Yet, when current and voltage are not properly in sync, then jitter/phase noise is the result. Literally, the speaker produces copious amount of noise patterns and results in a major reduction is clarity and natural tonality. It makes the speaker sound flat and uninteresting.

It is no secret that it is the Crossover that is a major culprit, but also the drivers themselves don't help. The driver that can be used with a Crossover technique that hugely suppresses phase noise, has to have special characteristics and they have to be lower in reactance that causes the driver to behave more like a voltage generator and do so at their worst in the midrange and lower treble.

The result is an incredible increase in overall clarity. Do you love vocal recordings, then you will love this speaker. Do you appreciate a huge soundstage with both unbounded width and height? Do you like hearing correctly proportioned instrument sizes within that soundstage and a total natural and non-edgy delivery and fully fleshed out tonal colours and natural overtones? Then this will be a speaker that would not be normally available at this price.

Locking in the Crossovers. Both mechanical High-Pass Filters (Box Alignments) and Electrical Filters (Crossovers)  can be current driven. When this is the case, both Box Alignments and Crossovers can be driven by any Amplifier, regardless of its type - no matter what it's output impedance is. So the Crossover does not shift and tracks near perfectly well, even when Tube Single-Ended Amplifiers are used, which typically have 5 Ohm Output Impedance or higher. This 'locking in' can even be adapted to High-Order Crossovers, but won't have the full CCD benefits - but at least the Crossovers stays where it should be.

Availability in late January 2014 expected. Crossover components used from Jantzen and Mundorf and other quality components (subject to change as we will always be looking for ways to improve).

This is an outstanding opportunity to avail yourself

of a remarkable speaker system.

PS: This speaker is the most Tube and Valve Amplifier friendly to an extent never seen before - it is a uniquely easy to drive and the recommended usage is 4 Ohm tap on most transformer coupled tube amplifiers. Also, these speakers can also be current driven, which currently no commercial loudspeaker can do (and indeed may be damaged by it). This is a direct result of the Crossover technology used and one that is slated to be used in future Orpheus and possibly also Duntech designs.

We know that the above reference to "CCD" Crossover Technology will raise eye-brows and here we go again and then think this is just another one of those faux technology claims we get ad nauseum, only to disappear as just another cyclic marketing tool becomes redundant.

Not so!

The truth is that some serious research is being done and a recognition that a new mathematical model needs to be developed that explain circumstances that Thiele-Small Parameters never anticipated and yet are compatible with that work - we know this because we use software based on Thiele-Small equations to exploit it experimentally - so we are looking at reconciling these effects with the existing mathematical models - not replacing them.

Originally Neville Thiele was able to grasp that electrical filter theory and the mathematics used to construct such electrical filters, could be transposed to mechanical filters as well, by finding equivalences in volume, compliance, Q factors and so on - later Richard Small defined losses that gave it an even more complete practical approach, so that mechanical High-Pass filters, which is what loudspeaker alignments are, could be defined and modeled by Thiele-Small Parameters.

But both electrical filters are defined by the impedance that drives them, and by default is assumed to be zero Ohm - unless that is allowed for, if above zero - then the drive impedance must become part of the parameters.

The problem is, that for loudspeaker mechanical High-Pass filters to function, to lock in the alignment of the box, it has to all practical purposes be driven by near zero Ohm, which defines a "voltage" source and hence the amplifier can produce current of any phase angle (whereas a true "current" source is high impedance and produces zero angle current phase at all times  - and that is the goal to aim at - and yet the alignment needs a defined "voltage" source to lock in the alignment - and now zero angle current phase is compromised. This is not compatible with current being the native method that the motor system in dynamic loudspeakers produce sound (hence erroneous current phase angle can be modulated to produce massive amounts of phase noise, or jitter).

The above not only applies to speaker box alignments when viewed as mechanical filters, but also defines similar problems with the Crossover.

Just as Neville Thiele found there was an equivalence between electrical filters and mechanical high-pass filters, we are now finding ourselves looking in reverse and seeing that what has be learnt about mechanical filters now can be applied to electrical filters as well - and loudspeaker systems uses both mechanical (box alignment) filters and electrical (Crossovers) filters - and we are in a sense reversing the thought that originally inspired Thiele, completing a kind of circle.

What is also interesting, from a historical view, is that this is happening here in Sydney, the very City that produced Thiele-Small Parameters - and it seems appropriate that in this City of Sydney is still at the forefront - now from individual developers (audiophiles) rather than university academics.

Stay tuned as this is a topic that continues...

Joe Rasmussen


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Last modified: Monday June 08, 2015

Just had a terrible thought. If "intelligent design" is unscientific, then who will design our audio equipment?