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McIntosh MX121 Home Theater Pre/Processor w/Dolby TrueHD, DTS-HD

Sale price£2,350.00 Regular price£2,743.00
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Mcintosh Mx121 Home Theater Pre/Processor W/Dolby True Hd Dts-Hd Preamplifier

McIntosh MX121 Home Theater Pre/Processor w/Dolby TrueHD, DTS-HD

SkyFi 479

Pickup available, usually ready in 24 hours

479 South Broad Street
Glen Rock NJ 07452
United States


This listing is for a MX121 set from McIntosh with an official McIntosh shipping carton, manual, and remote control.

Almost as capable as the latest version (MX123) at a fraction of the cost, yet still able to manage HDMI signals. If you require 4K video you would just connect your sources directly to the TV and use this unit for audio processing which is where McIntosh shines.

Using the built-in Audyssey DSX® Auto Setup you'll avoid fiddling with individual bands, settings, etc., to get the best sound possible in your home theater. (Note: Audyssey microphone and stand not included, but are easily found online).

Yes some of the HDMI features and standards may be older, but best results are usually achieved from running your sources directly to your display from experience.

We have many multi-channel amplifiers available as of this writing, and of course you can pair this with higher-end stereo only amplifiers from McIntosh, Audio Research, Krell, etc to truly customize your home theater amplification per channels/front and rear soundstage.

This MX121 was also updated to the very latest firmware version available.

Brand Background:
McIntosh Laboratory is an American manufacturer of handcrafted high-end audio equipment based in Binghamton, New York. The company was founded in 1949 by Frank McIntosh. The company designs and produces audio amplifiers, stereo tuners and other consumer electronics products.

Single Owner

HDMI, RCA and XLR. Removable power cord.

General Sound:
Accurate to the recording

Cosmetic Condition:
8/10 = Very Good. Excellent front faceplate, one minor flaw on chassis side or top.. See our detailed rating description here.

Unit, remote, manual and power cord.

Original Manufacturers Packing

McIntosh Performance Features Include:
• HDMI 1.4a with 3D Passthru Switching
There are six HDMI 1.4a Inputs. HDMI Output 1 includes the new Digital Audio Return Channel (ARC) signal from the TV1, thus eliminating the need for an extra cable and simplifies operation. HDMI inputs are compatible with Deep Color, x.v.Color, Auto Lipsync and HDMI Component Control.

• Analog Video/Audio Switching with Scaling
Component Video Inputs and Composite Video Inputs (Analog Video Signals) are also converted to a Digital Video Signal with resolution up to 1080P at the HDMI Outputs.

• Balanced Inputs and Outputs
A pair of Balanced high level Inputs and an eight channel Balanced Output are provided, permitting long cable lengths without a loss in sound quality.

• Moving Magnet Phono Input
There is a Precision Phono Preamplifier for Moving Magnet Cartridges.

• Built-in Dolby True HD and DTS-HD Master Decoders
The MX121 also provides built-in decoding of the Dolby Pro Logic IIz, Dolby Pro Logic IIx, Dolby Digital EX, DTS Neo6 and DTS-ES Sound Tracks.

• Internet Streaming
The MX121 when connected to a network, offers Internet Radio, with music and photo streaming.

• Audyssey DSX®
Audyssey DSX is a scalable system that adds new speakers to improve surround impression. Audyssey DSX first adds Wide channels for the biggest impact on envelopment and then creates Height channels to reproduce the next most important acoustical and perceptual cues. Surround Envelopment Processing is used to enhance the blend between the front and surround channels.
Audio Specifications

Unless otherwise noted, the below MX121 Specifications where taken with Audyssey bypassed and manual Tone/EQ set to flat setting.

Frequency Response
±0.5dB from 20Hz-20,000Hz

Total Harmonic Distortion
0.005% maximum from 20Hz to 20,000Hz at rated output

Signal To Noise Ratio
Phono: 86dB below 10mV input (A Weighted) 
High Level: 96dB below rated output (A Weighted)

Rated Output Voltage
2.5V Unbalanced Outputs (Main Zone) 
5.0V Balanced Outputs (Main Zone)

Maximum Voltage Output
6V Unbalanced 
12V Balanced

Output Impedance
220 ohms

Input Impedance
Phono: 47k Ohms, 65pf
High Level: 20k Ohms Unbalanced and Balanced

Sensitivity for Rated Output
Phono: 4.5mV
High Level: 450mV Unbalanced, 900mV Balanced

Maximum Input Signal
Phono: 50mV
High Level: 4.5V Unbalanced and Balanced

Tone Controls
Bass Control: ±6dB at 30Hz 
Treble Control: ±6dB at 10,000Hz

Video Specifications
Signal System

Version 1.4 (includes support for Deep Color, x.v.Color, Auto Lipsync, Audio Return Channel and HDMI Component Control) 

Analog Video Inputs scaled to a 1080P Digital Signal

Component Video Output Level
Y Output Level 1.0Vp-p (75 OHM) 
PB/CB Output Level 0.7Vp-p (75 OHM) 
PR/CR Output Level 0.7Vp-p (75 OHM)

Composite Video Output Level
1Vp-p (75 OHM)

Width is 17-1/2 inches (44.45cm)
Height is 7-5/8 inches (19.37cm) including feet
Depth is 19-1/2 inches (49.53cm) including the Front Panel, Knobs, Rear Panel Connections and USB Drive

30 lbs.

Link to Manual:
Click Here

Recommended Cables:

Kimber Kable - RCA Interconnects - Better

Kimber Kable - RCA Interconnects - Best

Kimber Kable - BALANCED XLR Connectors - Better

Kimber Kable - BALANCED XLR Connectors - Best

Kimber Kable - Coaxial Digital Interconnect

Kimber Kable - Optical Digital Interconnect

Kimber Kable - Power Cords - Better

Kimber Kable - Power Cords - Best

Testing Process:

We start with a visual inspection of all internal components to make sure that there are no signs of heat stress or damage. Capacitors are checked for telltale signs of predictive failure including bulging, shrunken wrappers, or physical leakage. We also inspect the PCB’s for discoloration from resistors or transistors that may have been running hot. On vintage units we often spot check select capacitors for value and ESR.

When we first power on a preamplifier we connect its RCA output to a Sencore PA81 Power Analyzer which simulates real world loading conditions and gives us an oscilloscope interface. The first order of business is checking that the volume control works smoothly throughout its entire range with acceptable channel balance. This is accomplished by feeding a 1KHz sine wave into one of the preamp’s line level inputs while monitoring the preamp’s output on an oscilloscope. We then switch to a 1KHz square wave to test the tone controls, loudness function, and filters where applicable. During this step we are watching for equal alteration of the test signal by both channels. This also helps us identify dirty controls that will need treatment. Once the basic line stage functions are verified, we test each input individually. This is especially important for devices that use relays to select their sources. If the preamp is equipped with a phono stage we test that as well. We use an inverse RIAA filter which allows us to feed a reference test signal into the phono input with the proper RIAA equalization and level. A square wave or sine sweep is used to verify that the device’s phono stage is faithfully reproducing the RIAA curve. If the preamp under test has balanced inputs and/or outputs these are tested as well.

We finish up our bench testing with a listening test with our bench amplifier and reference speakers. During this test we check for hum or hiss that may not have shown up in earlier testing. We also check that all of the tone controls and filters perform as expected. If the preamplifier has remote control functions these are also tested. Preamps with tube circuits or complicated power supply topologies are connected at our long term test rig for extended stress testing under real world conditions.

SKU: 103861
Mcintosh Mx121 Home Theater Pre/Processor W/Dolby True Hd Dts-Hd Preamplifier
McIntosh MX121 Home Theater Pre/Processor w/Dolby TrueHD, DTS-HD Sale price£2,350.00 Regular price£2,743.00