McIntosh MX136 Guide

The New McIntosh MX136, design theory and customer benefits.

The sixth generation MX136 is a continuation of the highly successful MX family of
McIntosh preamp processors.

McIntosh’s goal with these units has always been to bridge the needs of the Audio-Video
user with those of the Pure Audio customer. Each generation of processor has moved
closer in performance to our two channel preamps as these pre amps also continue to
evolve and improve. The two channel C-series preamps have received the benefits of
programmability, pioneered in the MX products, and allow customization of the
consumer’s system. The MX products have moved closer to the performance of the C­series preamps where the MX136 is designed to function as the pure analog C45 when
used in two channel modes. In addition to the feature set of the C45 the MX136 adds
video switching, video scaling and trans-coding, high quality stereo digital to analog
conversion at a 24 bit data rate, along with all Dolby and DTS multi-channel film and
video decoding formats up to 7.1 cinema modes.

Compared to the previous MX135 the MX136 has added features that allow for a
seamless combining of traditional video sources with the latest HD - HDMI video source
components such as the MVP871 DVD player, HD broadcast, HD satellite or HD cable.

MX136 video switching matrix:
Each of the 11 source inputs of the MX136 offer two channel RCA type audio inputs as
well as composite and ‘S’ video connections. Five assignable Component video inputs
and 4 assignable HDMI inputs are also offered.
This design allows the continued use of older video source components as well as the
latest HD digital video sources. This mix of components can be used with a single HDMI
cable running from the MX136 to the HD display monitor. Furthermore any composite
input can be up-converted to ‘S’ video or Component video. After conversion to, or
existing as analog component, any video source may be scaled into digital HDMI for
output to a HD video monitor. The HDMI digital video output may be set to Auto or
locked into the common display data rates of 480i, 480p, 720p, or 1080i. The chosen
output data rate will depend on the type of display monitor used.
When an HDMI video source is used the MX136 will pass the signal unaltered except for
buffering the input and output so the source to MX136 cable length does not add to the
MX136 output to video monitor cable length. Pure 1080P throughput is maintained on
the highest quality sources.
All video sources that are up-converted and scaled will also appear in their native format
as all video types switch together.

Pure Audio Features- Two sets of balanced stereo Inputs have been added and both
balanced and unbalanced front L + R Stereo Outputs are available.

A built-in Phono pre amp section has been added to the AUX input, which may be set to
Phono, Aux RCA jack or one of the balanced inputs. This is the same phono preamp
section we use in the C-series pre amps.
Both Balanced inputs are assignable to any of the 11 inputs, including the 12

th

tuner
input.
Pure audio modes that bypass all DSP processing are, Pure Stereo, Two Channel and the
eight channel External inputs. The MX136 Two-Channel mode functions just like a
normal two channel preamp for both analog and digital two channel sources. Only the
front left and right speakers are used full range regardless of set up menu settings. The
second stereo mode is Pure-Stereo. In Pure Stereo analog stereo audio sources are played
back with the left and right front speakers crossed over at 80 Hz to the sub using an
analog crossover. For the sub crossover to work in Pure Stereo the front left and right
speakers will need to be set to small in the set up menu. This allows full range operation
in Two-Channel and operation with the sub in Pure-Stereo. If a digital source is used in
Pure-Stereo the crossover point will be that set in the set up menu which is adjustable
from 60 to 120 Hz.
The 7.1 analog External inputs may be assigned when decoding from an outside source
such as a 7.1 output from a Blu-Ray or HD-DVD player.
Input 1 out of the 12 available is shipped in the AUX, Auxiliary mode. This initial setting
is fine for a variety of high level audio sources. When a customer wants to use a turntable
this input may be set to Phono in the set up menu which will activate the MM phono
stage, identical to the high quality phono stages used in the C45 and C46 stereo preamps.
The dedicated Tuner input allows the use of an external tuner or the superb optional
TM1, AM/FM + Powered AM antenna module, which installs inside the MX136 chassis.

If a consumer has a high end two channel set up with large speakers and dedicated amps
they may play this as a pure stereo system without compromise. Where many other high­end preamp processors are wedded to a digital signal path, the MX136 has both the Pure
Analog and advanced digital options. Conversely one can play a vinyl record or any other
legacy source and process the sound to play back in all the speakers, just like modern
multi-channel software.

Balanced audio outputs are available on all eight channels as well as RCA and the DB25
multi pin connector. This makes for three parallel A- Zone 7.1 output paths, all
simultaneously controlled by the same volume controls.
Inputs are either RCA stereo on all inputs or two assignable stereo Balanced Analog
Inputs. Six Digital Inputs are assignable to any input through the set up menu
programming. This allows industry-leading flexibility with current and all past sources.
When a consumer uses the MX136 all of their sources can be utilized without the need
for add on boxes, complexity, or sonic compromise.
The B-Zone may now be controlled from the front panel. Simply pressing the B-Zone
button will switch the front panel controls to B-Zone control for 5 seconds. Pushing the
red Power button will turn the B-Zone on. Source selection and volume level can then be
set. If no further volume changes are made the control will revert back to A-Zone control.
This also allows on / off switching and input selection of the B-Zone.

Both turn-on Minimum and Maximum volume levels are now programmable for the A
and B-Zones in the set up menus. This feature allows further system customization.

The Digital Engine in the MX136 is very advanced and cutting edge. To quote the
McIntosh design engineers:

“The MX136 uses the new TMS320DA610 ‘AUREUS’ DSP engine from Texas
Instruments. The DA610 is the same advanced DSP that Dolby Laboratories used to
develop the new Pro Logic II x enhanced surround sound technology. At 225 Mega Hertz
(MHz) the DA610 offers the highest performance in the audio industry with 1800 million
instructions per second (MIPS) or 1200 million floating-point operations per second
(MFLOPS)! Even the extremely demanding DTS 96/24 only takes up about 30% of the
processors available MIPS. This Floating Point processor allows for most processing to
take place in double precision (speed) which will reduce errors and therefore have higher
performance specifications and sound quality.”

This new 32/64 bit, floating point DSP engine also allows the MX136 to have the latest
Dolby decoding such as Pro Logic II x, and DTS Neo:6. These two decoding formats
allow two channel sources to play back in all eight channels or 5.1 sources to be
expanded to 7.1 channels.

The MX136 will accept 24/96 digital sources without down conversion and maintain full
24 bit 96 KHz, resolution. The MX136 decoder will be a sonic improvement over the
built-in decoders in most CD player or changer models. Running the digital data stream
into the MX136 for advanced decoding will upgrade the sound quality of most digital
sources.

A new DIGITAL SIGNAL LED has been added to the MX136 front panel display and
will light whenever the appropriate digital data steam appears on a selected input. Each
input can be programmed for playback mode and incoming signal type, analog or digital.
In the absence of the digital signal the indicator will not light signaling a source fault.

Just as in the previous MX132, MX134, and MX135, the MX136 utilizes individual
analog volume controls for each channel of the A and B Zone. This allows the MX136
digital processor to run at full bit for maximum digital to analog resolution regardless of
volume setting. This assures maximum multi-channel fidelity without the compromises
made by competing brands.

The front panel of the MX136 is 9” tall due to the added height of the balanced
connectors on the lower rear panel. This has allowed plenty of room for the 24 LED
format and mode indicators on the front panel.
The SEVEN input format indicators display what the incoming signal is, the EIGHT
Mode indicators display what processing / decoding is being done and the NINE Output
format indicators display which speakers are being used.

Renaming of all inputs with any four characters is offered on the MX136. This allows
customization to the user’s actual source components or some no one has thought up yet.
The MX136 features advanced Fiber-Optic lighting, which eliminates light bulb service.

The MX136 retains many of the popular MX features such as full RS232 function for
third party control, analog-domain tone controls on the Left, Center, Right and Sub
channels, Variable Loudness, Trim Memory for all inputs and modes, built-in 12 volt
power supply for third party IR sensors, and the bay for the high performance TM1 AM /
FM tuner option.

Of course the MX136 is fully field-upgradeable, through RS232 downloads.

Thank you and do not hesitate to send us your questions on the exciting new MX136,
Ron Cornelius, (
McIntosh Laboratory, Inc

[e-mail])