ML1 MKII

The McIntosh ML1 Mk II loudspeaker is a 4-way floorstanding speaker that brings the design of McIntosh’s first loudspeaker up to date. The original ML1 was introduced in 1970 with a mid-century modern appearance, high volume capability and strong bass response, particularly when used with an external equaliser. It was discontinued in 1977, after which McIntosh continued to produce high-performance loudspeakers. The ML1 Mk II returns to that starting point with current speaker technology.

The external design recalls the original ML1. Its cabinet is made from oiled American Walnut solid wood and veneers with a satin finish. A matching, magnetically attached and removable wood grille is covered with acoustically transparent black knitted cloth and finished with metal trim. The vertical wooden slats used on the original grille have been removed, leaving the new grille cloth unobstructed for music playback.

The speaker drivers are arranged symmetrically, so the ML1 Mk II does not have a dedicated left or right cabinet. This removes the possibility of installing the speakers in the wrong orientation and provides a more uniform listening area.

• Woofer: one 12" woofer in a sealed enclosure with a polypropylene cone and dust cap, plus synthetic rubber suspension.
• Lower Midrange: two 4" lower midrange drivers in a sealed sub-enclosure, also with polypropylene cones and dust caps with synthetic rubber suspension.
• Upper Midrange: one 2" soft dome upper midrange.
• Tweeter: one 3/4" Titanium dome tweeter, the same tweeter used in the XR50 and XR100 speakers.

A specially milled transition plate supports the midrange drivers and tweeter, allowing these units to sit close together. This reduces off-axis lobing and concentrates the acoustic output associated with imaging in a small area. The plate also provides a firm foundation for the upper-frequency drivers, helping to reduce unwanted vibration. Internal bracing creates an airtight enclosure that is separated from the 12" woofer section, further limiting cabinet vibration.

The upper midrange driver combines low resonance with high power handling. This allows the crossover between the lower and upper midrange drivers to avoid the 1kHz region, which is important for clear vocal reproduction. The tweeter crossover frequency reduces vertical lobing and allows the ML1 Mk II to reproduce the recorded signal with greater accuracy.

Power handling and amplifier compatibility

The McIntosh ML1 Mk II can handle up to 600 Watts from an amplifier. Its 5 separate drivers share the power load, allowing it to be used with high-power amplifiers such as the McIntosh MC611 and MC462. It can produce a life-sized sound that will fill all but the largest rooms.

The speaker is also suitable for lower-power amplifiers including the MC275, MC1502, MC830 and MC312. The ML1 Mk II can be bi-amped with the MC451 amplifier for further performance.

12" woofer and acoustic suspension enclosure

The 12" woofer extends the bass response down to 27Hz. Its surface area is equivalent to that of 4 6" woofers, allowing the single larger driver to move a substantial volume of air. The woofer is used in an acoustic suspension enclosure, as in the original ML1. Modern design and simulation tools were used to develop parameters that provide a bass response similar to the original speaker without requiring an external equaliser.

The woofer uses McIntosh patented Low Distortion High Performance, or LD/HP^®, Magnetic Circuit Design. This reduces distortion while increasing power handling and efficiency. The resulting performance allows the 12" woofer in the ML1 Mk II to rival woofers twice its size.

The 4-way design, driver selection and crossover network produce a wide listening area across all frequencies. Rather than restricting the full stereo sound stage to a narrow position directly in front of the speaker, the ML1 Mk II allows listeners throughout the room to hear the complete presentation.

Crossover network and connections

The custom-built crossover network is designed for power handling and durability. Over-specified components support high power levels, while solid-state, self-resetting protection devices protect the drivers from damage. The high- and low-frequency circuits are separated, with each available for bi-wiring or bi-amping.

Amplifier connections are made through gold-plated Solid Cinch^™ speaker binding posts. These attach speaker cables securely to help prevent them coming loose and causing a short, while the gold plating helps prevent corrosion and maintains the signal path through the speaker cables.

Matching stand and construction

The McIntosh ML1 Mk II is made in the USA and is supplied with a matching stand. The stand includes a vintage die-cast aluminium McIntosh name badge on its base, matching the badges used on some McIntosh amplifiers and integrated amplifiers.

The stand positions the loudspeaker for imaging and listening. It includes feet for hard floors and spikes for carpet. The speaker may also be placed directly on the floor or on sturdy furniture without decorations or other items that could vibrate.