McIntosh MC3500 MkII 350W mono tube power amplifier

• 350W monoblock
• Inspired by the original 1968-71 MC3500 - the amp that inspired an entire generation
• Powered by eight EL509S high power tubes
• Power Guard Screen Grid Sensor™, Sentry Monitor, rugged McIntosh pole screws
• Machined aluminum front panel with satin blown and gold anodized finish

Inspired by the amp that inspired an entire generation.

The historical significance of the 1969 Woodstock music and art fair cannot be denied. Nothing like it had been seen before, and many are of the opinion that nothing like it has been experienced since. In a crowd of over 400,000 people, many things could have gone wrong - and some things did. But one aspect that was generally agreed upon was how great all the musicians sounded. This sound quality is due in part to the McIntosh MC3500 tube amplifiers that exclusively powered the sound system used at Woodstock. Later, the MC3500 played a central role in many other significant musical events.

Original McIntosh MC3500 tube amp

One of the original McIntosh MC3500 amplifiers used at Woodstock on display at the Bethel Woods Center for the Arts.

It was 2019 when, at an event to celebrate the 50th anniversary of Woodstock, McIntosh President Charlie Randall realized the MC3500's historical value and dreamed of bringing it back into production. It didn't prove to be easy as the original model was first designed over 50 years ago. But after more than two years of development, the dream has come true as McIntosh proudly announces the MC3500 Vacuum Tube Amplifier Mk II.

New versions of the classic - Mk II

The MC3500 Vacuum Tube Amplifier Mk II is a conservatively specified 350 watt monoblock inspired by the original 1968-71 MC3500 and incorporates everything McIntosh has learned about tube amplifier design since the 1960s. It has been updated to modern standards and with modern components to deliver the same model numbering worthy sound reproduction as its classic predecessor. while following the original design as much as possible. Like the original MC3500, the MC3500 Mk II uses a Unity Coupled Circuit output transformer that allows all 350 watts to be safely transferred to virtually any speaker, whether its impedance is 2, 4 or 8 ohms.

The MC3500 Mk II is powered by eight EL509S high power tubes. The EL509S tube was specifically chosen because it shares many of the same features and characteristics as the 6LQ6 power tubes used in the original MC3500. Like the 6LQ6, the EL509S is extremely durable thanks to its robust cathode and associated heating element, which produces an exceptionally high peak current of over 1 amp.

Like the original MC3500, the MC3500 Mk II features a fully balanced driver section using three 12AX7A and one 12AT7 tubes. The first 12AX7A is a differential input amplifier; the second is a buffer/controller for the voltage amplifier; the third is a voltage amplifier. The 12AT7 is a buffer/driver for the EL509S output tubes. All pipes are located behind the power and output transformers and are protected by a two-millimeter steel cage, powder-coated black. The cage is designed so that the patented, gold-plated Solid Cinch™ speaker pole screws are easily accessible even when the cage is installed.

Our exclusive Power Guard Screen Grid Sensor™ (SGS) technology is included in the MC3500 Mk II. Power Guard SGS is designed specifically for tube amplifiers and is similar in nature to the patented Power Guard® technology used in McIntosh solid state amplifiers. Power Guard SGS helps to prevent premature failure of the pipe by monitoring the mains current leakage of the terminal pipes. If the current becomes too large, the Power Guard SGS activates a circuit that dynamically attenuates the input signal in real time to keep the tubes operating at a safe level. The fully balanced control stage of the MC3500 MK II is perfect for use with the Power Guard SGS. A Sentry Monitor™ that monitors the output current and shuts down the amplifier if it ever exceeds safe limits is also included.

The amplifier has both a balanced and an unbalanced input for connecting to a preamplifier. Balanced and unbalanced outputs are also included for multi-amp configurations such as bi- or tri-amping.

Just like the original MC3500, the Mk II version has a power meter, although it is larger and centered on the front panel instead of on the left side of the faceplate as in the original. This makes the meter easier to read and looks symmetrically elegant in a typical stereo system. The meter uses a customized version of our DualView™ Power Output meter design, where the upper scale shows power in watts and decibels, while the lower scale shows the amplifier's warm-up time. When the power is turned on, the meter slowly starts to rise. When the preheating is complete, the meter will go back to zero and the amplifier is ready to play music.

The MC3500 Mk II has handles just like the original, but with a more ergonomic design that's kinder to your hands when moving this 54.9kg mammoth. The bottom part of the frame is made of stainless steel, which has been polished to a mirror finish. The front panel is machined aluminum with satin-blasting and gold anodizing, mimicking the look and finish of the original MC3500. Clear glass covers the meter; the black glass at the bottom contains knobs and LED illuminated letters.

Paying homage to the look of the original MC3500, the Mk II features two U-shaped side rails that wrap around the top, back and bottom of each side. Many of the original MC3500 models were used a lot on the road and these side rails provided a lot of strength and durability. It's also a very unique design element that we wanted to replicate in the MC3500 Mk II. There were also four black rubber bumpers behind the rails, which allowed the amplifier to be temporarily stood upright when the system was assembled; the bumpers were large enough to keep the back of the amp from scraping against the floor and getting damaged. These bumpers are also duplicated on the MC3500 Mk II.

The MC3500 Mk II is perfectly modern and retro at the same time. It's inspired by the amp that helped inspire a generation. You can combine it with various preamps, turntables, CD players, streamers, speakers and other special products to create a complete home audio system.

• Amplifier power: 350W @ 2, 4 or 8 Ohms
• Harmonic Distortion: 0.3% (at any power from 250 milliwatts to 350 watts, 20 Hz to 20 kHz frequency band)
• Frequency response: 10 Hz to 70 kHz (+0, -3dB)
• Interference distance in the operating range: 120 dB
• Dynamic reserve: 2.4 dB
• Input sensitivity for maximum power: 3.8V XLR, 1.9V RCA
• Dimensions (W x H x D): 45.7 x 30 x 54.9 cm
• Weight: 54.9 kg