C55 2-Channel Solid State Preamplifier
 
16 inputs: 7 analog, 2 phono, 7 digital
Dedicated Subwoofer output
Controllable by McIntosh Connect app
Includes Processor Loop and 8-band analog equalizer
Supports 24-bit/192kHz and DSD512 files
Roon Tested
 
The C55 Preamplifier is a pinnacle of sonic excellence designed for audiophiles, music enthusiasts, and dedicated McIntosh fans alike. As a torchbearer of innovation, it takes the baton from its predecessor, the multi award-winning C53, and propels your home audio experience into new realms of audio nirvana. With precision and craftsmanship, the C55 proudly takes its place as a true industry leader.
 
INPUTS IN ABUNDANCE
 
With a staggering 16 inputs (9 analog and 7 digital), the C55 becomes the nerve center of your audio universe. Analog inputs include 3 balanced and 4 unbalanced connections, along with 2 phono inputs configurable for either Moving Coil or Moving Magnet phono cartridges to connect your turntable(s). Both phono inputs feature adjustable Gain in 6dB steps from 40dB to 64dB as well as RIAA equalization.
 
The digital section is housed in our DA2 Digital Audio Module and is powered by an audiophile-grade Quad Balanced, 8-channel, 32-bit Digital-to-Analog Converter (DAC). The DA2 offers an array of connections, including an audio-only HDMI Audio Return Channel (ARC)1 input, ushering your TV sound into a new era through your home stereo system. Dolby® and DTS® multi-channel audio formats are expertly converted to exquisite two-channel audio for a captivating listening experience.
 
The DA2's other 6 digital inputs consist of 2 coaxial, 2 optical, 1 USB, and 1 MCT. The USB input supports DSD512 and DXD 384kHz. The coax 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 on your SACD collection, the MCT input offers a secure, custom DSD connection when paired with our MCT series of SACD/CD Transports. The entire DA2 module is upgradeable and could be replaced by a future module should new digital technologies become available.
 
INNOVATIVE OUTPUTS FOR PERSONALIZED LISTENING
 
To connect the C55 to your power amplifier(s), there are 3 stereo sets of variable balanced and unbalanced outputs that offer advanced connection flexibility. All 3 sets of outputs can be active at the same time, and each can send the audio signal of the source component to 3 separate audio systems. 
The Main output and Output 1 have adjustable filtering capabilities for bi-amping, while Output 2 can be used to connect a subwoofer.
 
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 setup, the High Pass outputs could be connected to a vacuum tube amplifier, and the Low Pass outputs could be connected to a solid-state amplifier. The adjustable crossover allows you to optimize the performance of your amplifiers to your speaker’s specifications and to your listening preferences. Output 1 offers trim level control, which allows two different amplifiers to be volume balanced when bi-amping.
 
Furthermore, Output 2 can be configured as either mono or stereo and can send 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 features the return of the Processor Loop, something not available on the last few generations of McIntosh preamplifiers. The Processor Loop allows you to insert an external signal processor (such as our MQ112 Environmental Equalizer or MEN220 Room Correction System), dynamic range expanders, or other devices without having to place it between the preamplifier and power amplifier(s). This is usually more convenient and can allow for better performance.
The Processor Loop is also the perfect place to connect an analog tape recorder, a high-end cassette deck, or a 3-head reel deck that allows you to record from a source component and hear the recording just seconds later so you can monitor your recordings.
 
Specifications
 
Electronic Specifications
Number of Channels
2
Total Harmonic Distortion
0.005%
Frequency Response
+0, -0.5dB from 20Hz to 20kHz
+0, -3dB from 15Hz to 100kHz
Maximum Volts Out (Balanced / Unbalanced)
16V RMS / 8V RMS
Sensitivity High Level (Balanced / Unbalanced)
900mV / 450mV
Sensitivity Phono (Moving Coil)
0.45mV
Sensitivity Phono (Moving Magnet)
4.5mV
Signal To Noise Ratio (High Level)
100dB
Signal To Noise Ratio (Moving Coil)
80dB
Signal To Noise Ratio (Moving Magnet)
82dB
Voltage Gain (High Level)
15dB
Voltage Gain (Moving Coil)
Selectable 40dB, 46dB, 52dB, 58dB, or 64dB
Voltage Gain (Moving Magnet)
Selectable 40dB, 46dB, 52dB, 58dB, or 64dB
Input Impedance (Balanced / Unbalanced)
44K ohm, 22K ohm
 
Connectivity
Balanced Input
3
Unbalanced Input
4
Phono Input Moving Coil
Up to 2 (unit has 2 Phono inputs; each is user configurable as either Moving Coil or Moving Magnet)
Phono Input Moving Magnet
Up to 2 (unit has 2 Phono inputs; each is user configurable as either Moving Coil or Moving Magnet)
Upgradeable Digital Audio Module
Yes: DA2
Digital Coaxial Input
2
Digital Optical Input
2
Digital MCT Input
1
Digital USB Input
1
HDMI (ARC) Input
1
Digital AES/EBU Input
0
Balanced Fixed Output
0
Balanced Variable Output
3
Unbalanced Fixed Output
0
Unbalanced Variable Output
3
Headphone Output
1/4" High Drive with Headphone Crossfeed Director (HXD®)
Input Level Match
Yes, +/- 6dB
Home Theater PassThru
Yes
Unbalanced Analog Connector Type
Premium gold-plated solid brass
Service Port
1
Network Connection
1
 
Control
Tone Controls
8-band (each band adjustable ± 12dB )
Tone Bypass and Input Assign
Yes
RS232 Control Input
Yes
Power Control Output
1 Main, 4 Trigger
Rear Panel Data Port
6
Rear Panel IR Sensor Input
Yes
 
General Specifications
Multi-Chassis or Single
Single, two-layer
Output Meters
Yes
Vacuum Tube or Solid State
Solid State
Power Consumption (On)
75 Watts
 
Weights & Dimensions
Unit Dimensions (W x H x D)
17.5" (44.45cm) x 7.625" (19.4cm) x 16.5" (41.9cm)
Unit Weight
28 lbs (12.5 kg)
Shipping Weight
43.5 lbs (19.7 kg)