PM-KI Ruby


Stereo Integrated Amplifier

Enjoy enhanced quality audio with your speakers, audio source, and the Marantz PM-KI Ruby Stereo 200W Power Amplifier. It outputs up to 100W per channel RMS at 8 ohms and can drive 4 ohm speakers at 200W each. It features seven total stereo RCA inputs, including one reserved for a MM or MC turntable. Omitting the inclusion of any digital connectivity helps retain a clean path for the analog audio signal to pass through.

HDAM (Hyper Dynamic Amplifier Module) Technology

The onboard HDAM SA3 and SA2 are combined with an optimized circuit design layout to help provide enhanced sound quality and performance.

Marantz Musical Premium Phono EQ

Designed to deliver optimal sound by simplifying the signal path, the Marantz Musical Premium Phono EQ stage can be used with both moving magnet and moving coil cartridges thanks to a built-in MC head amplifier. Distortion is reduced by using two-stage amplification in the phono stage, and Maranz HDAMs are combined with JFETs (junction gate field effect transistors) in the output stage to provide high input impedance. The exclusion of coupling capacitors further simplifies the design, reducing signal distortion and enhancing signal purity.

Electronic Volume Control

The electronic volume control uses its IC to augment channel separation, dynamic range, and distortion reduction, while retaining the operational feel of an analog volume control device. This volume control is designed for high linearity as well.

Current Feedback Amplifier

Current Feedback amplification is engineered to match the requirements of Super Audio hi-res music for wide-bandwidth, high-speed reproduction. The impedance at the Current Feedback point is limited, generating a low phase shift. This reduces the need for phase compensation by minimizing Negative Feedback (NFB), simplifying the signal path, contributing to a high through-rate with enhanced transient response and sonic transparency across the bandwidth. Current Feedback also makes the amplifier insensitive to difficult speaker loads.

Designed to Deliver Power

The PM-KI Ruby is designed to maintain the purest possible sound and support the power needed for demanding speakers. The amplifier output stage delivers up to 100W per channel into an 8-ohm load, and can cope with high-impedance speakers as well, delivering up to 200W per channel into 4 ohms. The amplifier module connects directly to the rear panel PCB to help maintain signal purity and sound stability.

Pure Analog Amplifier

Rather than build a DAC into the amplifier, which would add noise within the chassis, the PM-KI Ruby is dependent on the DAC built into the audio source, eliminating interference with the analog signals passing through the amp to help maintain an analog environment that’s as pure and clean as possible.

Multiple Analog Inputs and Outputs

In addition to nickel-plated copper phono and CD analog inputs, the PM-KI Ruby features two line-level inputs and two pairs of recorder input/output jacks that allow the connection of multiple sources and recorders. You can use it as a standalone stereo amplifier for additional system configuration versatility with the power amp input, or connect the PM-KI Ruby to an external amplifier via the stereo pre-amp outputs.

Dedicated Headphone Output

Thanks to the onboard HDAM discrete modules, the headphone circuit is designed to deliver enhanced audio fidelity with a wide range of headphone types and impedances, including low-impedance headphones.


Number of Channels2
RMS Power Output
  • 2 x 100 W @ 8 ohms, 1 kHz, 0.05% THD
  • 2 x 200 W @ 4 ohms, 1 kHz, 0.1% THD
Frequency Response
  • 5 Hz to 50 kHz
  • CD Input: 5 Hz to 50 kHz ±3 dB @ 1 W, 8 Ohms
Signal to Noise Ratio
  • MM Phono: 88 dB
  • MC Phono: 75 dB
  • High Level: 107 dB (2 V Input)
Total Harmonic Distortion (THD)0.005% @ 8 ohms, 100 W, both channels driven
Damping Factor500 @ 8 ohms, 20 Hz to 20 kHz
Tone Control
  • Bass (50 Hz): ± 6 dB
  • Treble (20 kHz): ± 6 dB
Input7 x Stereo RCA (1 Phono with Ground Screw)
  • 2 x Stereo RCA
  • 1 x 1/4″ / 6.35 mm Headphone (Front)
Speaker Connectors2 x Binding Post Pairs
Other Connectors
  • 1 x RCA Remote In
  • 1 x RCA Remote Out
  • 1 x 1/8″ / 3.5 mm Floating Control Bus In
  • 1 x 1/8″ / 3.5 mm Floating Control Bus Out
Input Sensitivity
  • CD/Line/Recorder Inputs: 220 mV / 13 kilohms
  • MM Phono: 2.3 mV / 39 kilohms
  • MC Phono: 250 µV / 100 ohms
  • Power Amp In: 1.1 V / 13 kilohms
Input Level
  • MM, Maximum Allowable: 80 mV @ 1 kHz
  • MC, Maximum Allowable: 8 mV @ 1 kHz
RIAA Equalization Deviation± 0.5 dB, 20 Hz to 20 kHz
ChassisDouble-Layer with Aluminum Panels
Front PanelAluminum
Power Requirements120 VAC, 60 Hz
Power Consumption
  • Operational: 130 W
  • Standby: 0.2 W
Dimensions (W x H x D)17.32 x 5 x 17.83″ / 43.99 x 12.7 x 45.29 cm
Weight34.61 lb / 15.7 kg


Product Type

Stereo Integrated Amplifier

Marantz employs product designers and engineers with over 30 years of know-how and experience. They perform over 50 different quality validation and assurance tests for every piece that ships with the Marantz name on it. Every Marantz takes years of up-front design detailing, sound obsessing, and experience validation before they deliver a single unit to you. And they continue testing throughout the product’s life. Everything they know and everything they do is intended to make your Marantz ownership better. That’s the real value of 70 years.