• Collector‘s item
• Individually numbered
• Limited to 1.000 sets
The KI Way.
Few hi-fi companies, if any, can say that one person has steered their sound for four decades – like Ken Ishiwata does at Marantz. The KI Ruby SACD player and amplifier go beyond even the standards of past KI Signature achievements, embodying all of Ken Ishiwata’s experience and expertise. Therefor they carry Ken Ishiwata’s signature as integral part of their design.
The Early Years.
Ken Ishiwata has been at the heart of Marantz for 40 years, but his influence extends beyond the many wonderful products he has developed for the company in that time.
A Special Way of Listening.
He has a unique ability to conceptualise stunning sound reproduction, design the equipment required to achieve it, and then deliver enthralling demonstrations around the world leaving listeners spellbound with the new insights Marantz products can deliver into even the most familiar music.
Refining the Harmony.
In exploring every aspect of every design, just occasionally he finds a product with extra potential, which he can then take beyond the Marantz standard and into something even more special. A KI Signature product is born.
Bringing Listeners Closer to Music.
The knowledge of how to make a fine-sounding product truly magical has grown with each new KI Signature launch – by improving sound-critical components through a process of careful selection and subtle blending, testing, listening and testing again.
The PM-KI Ruby Amplifier.
The PM-KI Ruby is built with just one aim – audio performance – which is why it uses a fully discrete two-stage design with separate power supplies for the preamplifier and power amp section to reduce interference, and draws on the design of the flagship PM-10 amplifier with its moving coil/moving magnet phono stage and Marantz HDAM technology throughout for signal purity.
The PM-KI Ruby at a glance.
- Engineered and extensively tuned by a team led by Ken Ishiwata, drawing on more than 65 years of Marantz amplifier design knowledge
- Marantz high-resolution preamplifier stage using proprietary HDAM technology
- Switching power amplifier design derived from flagship PM-10 amplifier
- Generous output: 100W + 100W (8 ohm), 200W + 200W (4 ohm)
- Fully-discrete two-stage design for signal purity, with separate power supplies for preamp and power amplifier sections to reduce interference
- Toroidal transformer dedicated to preamp for clarity and precision sound
- Dedicated headphone amplifier with alldiscrete construction featuring HDAM-SA2
- Linear volume control with new electric volume system
- Laser-engraved ‘Ken Ishiwata’ signature and Ruby motif, marking Ken Ishiwata’s 40 years with Marantz
PM-KI Ruby Highlights
The premium built
It’s all built on a vibration-resistant double layer chassis for rigidity, with 5mm thick aluminum top lid, solid aluminum front, copper plated chassis and massive insulators.
It is equipped with high-quality nickel-plated input terminals and high-purity copper speaker connections.
The PM-KI Ruby features a current feedback design with newly-developed wide-range circuitry and a toroidal transformer dedicated to preamp for clarity and powerful sound.
The HDAM® SA3 circuitry offers the cleanest signal path and optimal dynamics through the amplifier, which delivers 100W per channel into 8ohm speakers, or 200Wpc into 4ohm. The audio signal path is made entirely from discrete components for optimal quality, with the RIAA equalization split into passive and active components: RIAA correction is carried out by a Marantz HDAM, while the all-discrete amplification runs in minimum-distortion Class A.
The phono stage
This is designed to deliver optimal sound quality by simplifying the signal path, the Marantz Musical Premium Phono EQ stage in the PM-KI amplifier can be used with both moving magnet and low-output moving coil cartridges, thanks to a built-in MC head amplifier.
And the design is all about lowering distortion by using two-stage amplification, combining Marantz HDAMs with JFETs (junction gate field effect transistors) in the input stage, giving high input impedance. This allows the no-negative-feedback design to be further simplified by the deletion of coupling capacitors – all then shielded – again reducing distortion and enhancing signal purity.
Laser engraved signature
Marantz has been designing and making amplifiers for more than 65 years, and for 40 of those the products have reflected expertise of Ken Ishiwata.
Now, to mark his four decades with the company, the PM-KI Ruby amplifier has been developed and tuned by a highly experienced engineering team led by KI himself. And it arrives bearing Ken Ishiwata’s signature and a special Ruby motif.