The Kii Three has always, in my perception, been emblematic of the most clever technique and thoughtfulness of Bruno Putzeys.
Impressive... most impressive.
Like the Dutch & Dutch 8C, it proposes to develop a cardioid in room response profile,
Yet, at the same time, I must offer the opinion that it may suffer in some regards from the same level of complexity and tradeoffs inherent in this approach as implemented by the D&D 8C.
This introduction from the Six Moons review can convey key aspects of the configuration, as well as some concerns, yet still miss some more subtle yet important issues that were addressed successfully in early designs such as the Natalie P, which cannot be addressed by this approach.
The overall result from this level of complexity hints at a design group quite strong in the Force- how much is Dark Side and how much otherwise would be a matter of personal assessment and judgement. But, as with Dutch and Dutch, I would urge caution- "Don't be too proud of this technological terror you've constructed...."
For example, are your DACs comparable to a standalone product such as a TotalDAC D1? A Benchmark DAC3? Or even a Soekris 2541?
And what standard of performance is your ADC? And your master clock?
An interesting technical report is available from Audio Xpress, but curiously, it does not address measured distortion...
And, let's consider driver resonances... one not inconsiderable flaw regarding DSP notch filters is that they have no impact on the generator impedance of the driver at those frequencies, and as a result do NOT reduce resonant amplification of distortion products- a factor taken into account for the Natalie P, and other subsequent designs, but not addressable by DSP. Of course, Bruno's newest association with PuriFi has even relatively recently published an Application note addressing this very same topic.
Given this driver set, and previous design techniques as implemented as long ago as the Natalie P, and as recently as the passive voicing module, is an alternative solution worthy of pursuit? And can it be made worthy of audition as well as detailed technical reporting?
Interesting questions to ponder....
But with some drivers in hand, and others on the way, this will no longer be a purely theoretical question.
One might justifiably advise to be careful not to choke on one's aspirations in this endeavor...
But I have cause to believe that the results will be interesting, most interesting.
To naysayers, I would only offer that I find your lack of faith disturbing...
Impressive... most impressive.
Like the Dutch & Dutch 8C, it proposes to develop a cardioid in room response profile,
Yet, at the same time, I must offer the opinion that it may suffer in some regards from the same level of complexity and tradeoffs inherent in this approach as implemented by the D&D 8C.
This introduction from the Six Moons review can convey key aspects of the configuration, as well as some concerns, yet still miss some more subtle yet important issues that were addressed successfully in early designs such as the Natalie P, which cannot be addressed by this approach.
Wave shaping tech is key to Kii. This fully DSP-controlled active 6-driver compact breaks the rules. Its bass is actually directional. Cardioid aka heart-shaped dispersion is the technical term for its propagation shape. The upshot? Unlike conventional speakers, the Kii Three wants to be more blasé about room interference. It directs most of its sound at the listener, eliminating or at least attenuating side and especially rear radiation with strategic phase-canceling chicanery. This downplays usual room dependencies. It performs superior in far more real-world situations including very close to the wall. For a perfect step response of what is a three-way—reference this for the actual graph—its designers use minor time delay on their frontal drivers. This lets the side and rear woofers catch up.
That trick plus claimed 20Hz response can only do the work because filtering and compensation occur in the digital domain. Analog inputs must convert. By the same token, LF headroom must be lower than mid and high freqs because, to keep its box small, the Kii Three gooses bass gain on its built-in amps to offset natural roll-off. In payment for this, it abolishes your own amplification and D/A conversion. Its functional very high IQ relies on the designers controlling all the parameters, not letting us techno peasants piecemeal it. This eliminates the lego and puzzle crowd who insist on arbitrary system assemblage. Au revoir, amigos. Those who—gasp!—are still with us have notions:
That trick plus claimed 20Hz response can only do the work because filtering and compensation occur in the digital domain. Analog inputs must convert. By the same token, LF headroom must be lower than mid and high freqs because, to keep its box small, the Kii Three gooses bass gain on its built-in amps to offset natural roll-off. In payment for this, it abolishes your own amplification and D/A conversion. Its functional very high IQ relies on the designers controlling all the parameters, not letting us techno peasants piecemeal it. This eliminates the lego and puzzle crowd who insist on arbitrary system assemblage. Au revoir, amigos. Those who—gasp!—are still with us have notions:
• that Putzeys & Partners also exploit DSP to improve their matching tolerances between drivers
• that they use DSP to enable their 15-click 'contour' knob with its preset EQ curves
• that they use DSP for their 16-click 'boundary' trim pot which adjusts bass compensation for free field, wall and corner placements (the latter two require consecutively less compensation due to boundary gain)
• that their current and voltage 'motion-control' loops are somehow connected to the far earlier motional feedback as mentioned in the 40-year old Philips ad at right.
• that home-theatre users might have latency issues of syncing dialogue to on-screen action given the speaker's digital delay and intensive processing1
• wonder about out-of-standby delays2
• that they use DSP to enable their 15-click 'contour' knob with its preset EQ curves
• that they use DSP for their 16-click 'boundary' trim pot which adjusts bass compensation for free field, wall and corner placements (the latter two require consecutively less compensation due to boundary gain)
• that their current and voltage 'motion-control' loops are somehow connected to the far earlier motional feedback as mentioned in the 40-year old Philips ad at right.
• that home-theatre users might have latency issues of syncing dialogue to on-screen action given the speaker's digital delay and intensive processing1
• wonder about out-of-standby delays2
The overall result from this level of complexity hints at a design group quite strong in the Force- how much is Dark Side and how much otherwise would be a matter of personal assessment and judgement. But, as with Dutch and Dutch, I would urge caution- "Don't be too proud of this technological terror you've constructed...."
For example, are your DACs comparable to a standalone product such as a TotalDAC D1? A Benchmark DAC3? Or even a Soekris 2541?
And what standard of performance is your ADC? And your master clock?
An interesting technical report is available from Audio Xpress, but curiously, it does not address measured distortion...
And, let's consider driver resonances... one not inconsiderable flaw regarding DSP notch filters is that they have no impact on the generator impedance of the driver at those frequencies, and as a result do NOT reduce resonant amplification of distortion products- a factor taken into account for the Natalie P, and other subsequent designs, but not addressable by DSP. Of course, Bruno's newest association with PuriFi has even relatively recently published an Application note addressing this very same topic.
Given this driver set, and previous design techniques as implemented as long ago as the Natalie P, and as recently as the passive voicing module, is an alternative solution worthy of pursuit? And can it be made worthy of audition as well as detailed technical reporting?
Interesting questions to ponder....
But with some drivers in hand, and others on the way, this will no longer be a purely theoretical question.
One might justifiably advise to be careful not to choke on one's aspirations in this endeavor...
But I have cause to believe that the results will be interesting, most interesting.
To naysayers, I would only offer that I find your lack of faith disturbing...
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