McIntosh C55 AC Solid-State- Preamplifier

The C55 AC preamplifier is a pinnacle of sonic excellence, designed for audiophiles, music enthusiasts and die-hard McIntosh fans alike. A torchbearer of innovation, it picks up the baton from its award-winning predecessor, the C53 AC, catapulting your home audio experience into new realms of sonic nirvana. With precision and craftsmanship, the C55 AC proudly asserts its place as a true industry leader.

ENTRANCES IN ABUNDANCE

With an impressive 16 inputs (9 analog and 7 digital), the C55 AC becomes the center of your audio universe. Analog inputs include 3 balanced and 4 unbalanced connections, as well as 2 phono inputs configurable for moving coil or moving magnet phono cartridges to connect your turntables. Both phono inputs have adjustable gain in 6dB steps from 40dB to 64dB as well as RIAA equalization.

The digital section is located in the DA2 Digital Audio Module and is powered by an audiophile quad balanced, 8-channel, 32-bit digital-to-analog converter (DAC). The DA2 offers a range of connections, including an audio-only HDMI Audio Return Channel (ARC)1 input, taking your TV's sound through your home stereo system into a new era. Dolby® and DTS® multi-channel audio formats are masterfully converted into exquisite two-channel audio for an immersive listening experience.

The other 6 digital inputs of the DA2 consist of 2 coaxial, 2 optical, 1 USB and 1 MCT input. The USB input supports DSD512 and DXD 384kHz. The coaxial and optical inputs decode digital music up to 24-bit/192kHz for high-resolution audio playback. And to get the best sound quality from the high-definition audio in your SACD collection, the MCT input provides a secure, dedicated DSD connection when combined with the MCT series of SACD/CD transports. The entire DA2 module is upgradable and could be replaced with a future module should new digital technologies become available.

INNOVATIVE OUTPUTS FOR PERSONALIZED HEARING

To connect the C55 AC to your power amplifier(s), there are 3 stereo sets of variable balanced and unbalanced outputs, providing advanced connection flexibility. All 3 sets of outputs can be active at the same time, and each can send the source component's audio signal to 3 separate audio systems.

Additionally, the main output and output 1 can be used for bi-amping a single speaker system via the built-in adjustable high-pass and low-pass filters. In this configuration, the high-pass outputs could be connected to a tube amp and the low-pass outputs to a solid-state amplifier. The adjustable crossover allows you to optimize the performance of your amplifiers according to the specifications of your speakers and your listening preferences. Output 1 provides trim level control, allowing two different amplifiers to be volume balanced when bi-amping.

Additionally, Output 2 can be configured as mono or stereo and can send the audio signal to a stereo audio system in another room, to a single mono subwoofer, or to 2 separate stereo subwoofers.

RETURN OF THE PROCESSOR LOOP

The C55 AC features the return of the processor loop, something not available on previous generations of McIntosh preamps. The processor loop allows you to insert an external signal processor (such as the MQ112 Environmental Equalizer or MEN220 Room Correction System), dynamic range extenders, or other devices without having to place them between the preamplifier and the power amplifier(s). This is typically more convenient and can provide better performance.

The processor loop is also the perfect place to connect an analog tape recorder, high-end cassette deck or 3-head reel device, allowing you to record from a source component and hear the recording just seconds later, allowing you to enjoy your recordings can monitor.

NETWORKED FOR CONTROL AND UPDATES

In addition to using the included remote control or front panel controls, the C55 AC can be connected to your network, unlocking control options through the free Connect app (due for availability April 2024). Designed for Android and Apple devices, the Connect app can be used to control key functions of the C55 AC, including volume control and input and output selection.

Select McIntosh source components connected to the C55 AC with a data cable can be partially controlled via the app's source control function. Source control allows users to control many functions of the source unit through the app, such as changing radio stations on a tuner or playing a disc in a CD player. This feature brings added convenience to setups that have a second set of power amplifiers and speakers connected to one of the C55 AC's outputs, such as an outdoor system that no longer requires you to go into the house to control its basic functionality.

ADDITIONAL FEATURES

8-band analog equalizer to fine-tune your music with precision, for a personalized sound experience (the equalizer can be bypassed if necessary).
High Drive headphone amplifier with Headphone Crossfeed Director (HXD®) technology brings an additional dimension to headphone listening.
Home Theater PassThru for seamless integration into your home theater system.
Received the Roon Tested award from Roon Labs.
Power Control allows you to easily turn other connected McIntosh components on and off.
Data ports can send remote control commands to connected source components.
Electromagnetic input switching for reliable, noiseless and distortion-free switching.
Level Trim Adjustment for equalizing the levels of analog inputs to avoid abrupt changes in volume.
Precisely balanced, digitally controlled attenuation system for precise volume control with 0.1dB accuracy.
Fully regulated power supplies and a dedicated R-core power transformer for stable, noise-free operation.
Environmentally friendly power management system that turns off the device after 30 minutes of inactivity (can be disabled).

Elevate your listening journey

All of this cutting-edge technology is housed in the iconic McIntosh design - a black glass front panel adorned with blue blades, knobs and an illuminated logo. The polished stainless steel housing adds a touch of elegance, making it the perfect companion for amplifiers, CD players, turntables and more. Elevate your sonic journey with the C55 AC preamplifier.

TECHNICAL DATA

• Frequency response
  
  • +0, -0.5 dB from 20 Hz to 20,000 Hz
  • +0, -3 dB from 15 Hz to 100,000 Hz
• Total harmonic distortion: 0.005% from 20 Hz to 20,000 Hz
• Rated output
  
  • 2.5V unbalanced
  • 5V balanced (main output)
  • 450mV (Fixed output)
• Maximum voltage output
  
  • 8V effective value unbalanced
  • 16V rms symmetrical
• Sensitivity (for nominal output)
  
  • High level
  • 450mV unbalanced
  • 900mV balanced
  • Phono MM, 4.5mV
  • Phono MC, 0.45mV
• Signal-to-noise ratio (A-weighted)
  
  • High level - 100dB
    (Below rated output)
  • MM Phono - 82dB
    (Below 5mV input)
  • MC Phono - 80dB
    (Below 0.5mV input)
• Input impedance
  
  • High level
  • 22k ohm unbalanced
  • 44k ohms balanced
  • Phono 1, 2 (MM and MC): 25, 50,
    100, 200, 400, 1k or 47k Ohm 50
    up to 400pF in 50pF steps
• Maximum input signal
  
  • High level
  • 5V unbalanced
  • 10V balanced
  • Phono MM, 80mV
  • Phono MC, 8mV
• Equalizer controls: 25Hz, 50Hz, 100Hz, 200Hz, 400Hz,
  1,000Hz, 2,500Hz and 10,000Hz
• Voltage gain
  
  • High level to fixed output: 0dB
  • High level to main output: 15dB
  • Phono 1, 2 (MM and MC) Selectable
  • 40dB, 46dB, 52dB, 58dB or 64dB
• Output impedance
  
  • 100 ohms unbalanced
  • 200 ohms balanced
• Headphone load impedance: 100 ohms to 600 ohms
• Digital input sample rates
  
  • Coaxial: PCM -16Bit, 24Bit - 44.1kHz
    up to 192kHz
  • Optical: PCM - 16Bit, 24Bit - 44.1kHz
    up to 192kHz
  • USB: PCM - 16Bit, 24Bit, 32Bit -
    44.1kHz to 384kHz
  • MCT: PCM, SACD, -16Bit, 24Bit -
    44.1kHz to 192kHz / DXD -
    DXD352.8kHz, DXD384kHz DSD -
    DSD64, DSD128, DSD256, DSD512
  • HDMI: PCM 24Bit, 44.1kHz - 192kHz
    DTS, Dolby Digital
• Current control and trigger output: 12V DC, 25mA
• Power supply:
  
  • AC voltages: 100, 110, 120, 220, 230,
    240 volts, 50/60Hz at 75 watts.
  • Standby power, less than 0.5 watts
• Overall dimensions (W x H x D) in mm: 444 x 194 x 419
• Weight: 12.5kg