Stellar M1200 Mono Amplifier

1200 watt vacuum tube input power amplifier pair

Built in Boulder

The Stellar M1200 monoblock power amplifier combines the rich warmth and musicality of vacuum tubes with the jaw-dropping power and seemingly infinite headroom of a 1200 watt high-performance output stage. This extraordinary hybrid amplifier knows no limits. From the subtlest musical whisperings to the loudest crescendos an orchestra or rock band is capable of, Stellar M1200 never flinches. Regardless of your speaker’s power demands or limitations, enjoy the once unachievable uncompressed effortlessness afforded by this design. Pure musical bliss for any loudspeaker made, from the smallest to the biggest. Stellar.

The M1200 began as the dream project of PS engineer, Darren Myers who wanted to build a power amplifier without bounds or compression on even the loudest of musical passages, yet equally at home reproducing the subtlest of details.

To preserve both uncompressed dynamics as well as the tiniest of nuanced details requires a cost-no-object input stage, like that of a high-performance vacuum tube fed from its own analog power supply. The amp’s delicate input signals, now faithfully preserved by its vacuum tube input, then need to be amplified without restriction by taking advantage of a new type of Class D output power module. This extraordinarily high current, low distortion, MOSFET output stage combines state-of-the-art topologies with decades of design and listening experience to produce what we believe is the most musically satisfying amplifier of its kind.

The over-the-top high power output of the M1200 exists not to match a small handful of power-hungry speakers, but rather, to act as the perfect uncompressed power source for even the smallest, most efficient of speakers on the market.

Remember, power amplifiers deliver only the number of watts required by your speaker to achieve the desired loudness. Even the most powerful amplifiers deliver only what’s asked of them. What’s been missing in most amplifiers is adequate headroom and effortless linear performance—something only a vacuum tube-based powerhouse like the M1200 can unquestionably provide. From the most subtle of details to unheard of explosive dynamics, Stellar M1200 represents the pinnacle of high powered musicality that must be heard to be believed. Regardless of the power demands—or power limitations—of your loudspeakers, Stellar M1200 is the perfect choice if effortless musicality is in your future.

Specifications:

Stellar M1200 Mono Amplifier

Unit Weight27 lbs [12.2 kg] (each) Unit Dimensions17”W x 3.75”H x 12”D (13"D w/connectors)
17”W x 7.5”H x 12”D (Stacked)

Shipping Weight29 lbs [13.15 kg] (each)
Shipping Dimensions22”W x 8”H x 17”D (each) Color OptionsBlack
Silver Vacuum tube type12AU7 Voltage Options
(Factory set only)Japan 100V
North America 120V
Europe/Asia/Australia/New Zealand 230V Mains Power InputsIEC C14 Idle Power Consumption27W Power Factor>0.9 @ rated power 4Ω Accessories IncludedUS (NEMA 5-15P) (all versions)
Schuko (CEE7/7) (230V version)
UK (BS 1363) (230V version) Audio InputsRCA (Unbalanced)
XLR (Balanced) Speaker Outputs Copper base nickel plated binding posts (2 pair) DC Trigger Input 3.5mm 5-15VDC Warranty3 years parts and labor

Signal

Gain30.5dB +/-0.5dB Sensitivity for rated output power2.08V Signal to Noise1kHz@1200 Watts > 112dB Input impedance Unbalanced 50KΩ
Balanced 100KΩ Output Impedance50Hz, 2.8VRMS <0.007Ω Damping factor50Hz. 2.8VRMS
8Ω >1100
4Ω >550 Frequency Response2.8VRMS into 4Ω
10Hz – 20KHz +/- 0.5dB
10Hz – 45KHz +0.1/-3.0dB

THD&IM

1KHz, 1W/4Ω< 0.005% 10-20KHz, 1W/4Ω< 0.01% 1KHz, 150W/4Ω< 0.02%

Output Power

120vac mains, 1kHz, 1% THD 8Ω600W minimum 4Ω1200W minimum 2Ω

Stable for musical transients








FEATURES:

• Mono power amplifier pair
• Zero-loss Vacuum tube input stage
• Powerful MOSFET balanced output stage
• RCA Single ended input
• XLR “true” balanced input
• 600 watts into 8Ω
• 1200 watts rms into 4Ω
• 2Ω stable
• Damping factor >1100 for excellent loudspeaker control
• Efficient operation with very little heat
• ICE Edge technology
• Front panel standby button
• Efficient operation with very little heat
• Dual, solid copper, plated, output binding posts
• 27 pounds each
• Input 12 volt trigger

The Stellar M1200 mono amplifiers solve a classic problem with nearly every power amplifier made: sonic compression. When the orchestra gets loud and complex, or the band really starts to rock it out, most power amplifiers get out of their comfort zone and we hear their stress and strain as compression. The M1200 was designed to play any music into any loudspeaker with zero compression. Suddenly, more than just a sonic veil is lifted when a pair of M1200s are inserted. Where once music’s character was preserved on only soft to medium loud passages, with the M1200s in play, there’s no difference between the softest to the loudest complex passages known. Music is delivered without prejudice to the recording’s dynamics.

Rated at 600 Watts into 8Ω and a whopping 1200 Watts into 4Ω, the M1200 combines the best of two worlds: ultra-linear, high-current, ICE Edge Class D technology for the output stage; and a discrete, Class-A vacuum tube for the all-important input stage. The M1200’s rich, warm, and beautifully nuanced reproduction of music comes first from the zero feedback, class A vacuum tube input stage. Here nothing is lost in its hand-selected 12AU7 vacuum tube, fed from its own analog power supply.

Our mission with the Stellar M1200 was to produce a remarkably musical power amplifier without limitations, regardless of what speakers were paired with it. A common misconception in audio is that power amplifiers should be matched with loudspeakers by wattage: smaller sensitive speakers should be paired with small amplifiers and the opposite for larger, less sensitive speakers. The truth is, for a given loudness within a room all power amplifiers deliver the same wattage to match a loudspeaker’s sensitivity. What’s missing in most systems is a power amplifier with overkill-headroom.  Only then can we fully appreciate what a massive improvement unfettered dynamics brings to the system.

The M1200’s designer, PS Audio engineer Darren Myers, wanted to see what would happen when he combined one of the world’s highest power amplifier stages with a rich and warm vacuum tube input stage—the results set us all back on our heels. This hybrid approach combines the best of today’s technology with time-honored techniques leveraging PS Audio’s forty-plus years of experience.

The results are extraordinarily musical and dynamic, even on bookshelf loudspeakers. Never have listeners heard such uncompressed beauty from small or large speakers. This amplifier has transformed good to great in ways few among us have imagined possible. After hundreds of hours of tuning, voicing, and perfectionist tweaking, we were ready to release this extraordinary combination of power and delicacy to the world.

One listen to the Stellar M1200 pair and you’ll appreciate Myers’ dedication to musical truth without compromise.

The power amplifier is technology always present in stereo systems. Yet, despite the fact everyone uses them, few appreciate the power amp’s critical role in preserving music’s nuanced details because most amplifiers fail to preserve them. Overtones from plucked instruments, subtle cues defining placement, depth, soundstage width, and transient decays are often lost in the power amplifier.

The M1200 loses nothing. Stellar’s lead designer, engineer Darren Myers, was obsessed with its detail and voicing—lavishing great attention on even the tiniest nuances in the music. This helped Stellar capture the rich full-bodied essence of recorded music and presents it to your loudspeakers with authority and grace—with never a hint of glare or unnaturalness. The M1200 is faithful to the music like few amplifiers are.

The vacuum tube makes all the difference

The connection between preamplifier and power amplifier is critical, for it is at this junction where most essential musical details and dynamic contrasts are easily lost. Nothing in the design of a power amplifier is more important than its input stage when preserving music’s finest nuances. In the M1200 a zero feedback class A vacuum tube input stage captures every whisper of music while preserving intact the most dynamic crescendos and quick rise time transients with zero loss.

Long hours of listening and tuning sessions in Music Room One, shared by PS Audio founder Paul McGowan and Darren Myers, resulted in a sonic signature that honors the music and never draws attention to itself.

The listening experience with the M1200 is nothing short of a revelation. Where most amplifiers do their best to preserve dynamics, they fail to present them as if they were live. The M1200 eliminates the tendency of nearly every power amplifier to change its sonic character as the music gets louder. First time listeners to the M1200 are stunned at the ease and openness of music while expanding and then maintaining width and depth of the M1200’s soundstage; its preservation of the smallest details in reverb, room acoustics, musical overtones; its commanding presence without intrusion; it’s delicate handling of subtle shadings; its authority as it grabs hold of the loudspeaker and breezes through even the most complex musical passages.

The hybrid approach used in Stellar’s power amplifiers takes advantage of the best traits technology has to offer. Its all important input stage relies upon its 12AU7 vacuum tube to provide a zero-loss interface between the preamplifier or DAC, as well as imprint the amp’s sonic character. It is then time to convert the perfected analog voltage into the all important high current output needed to drive loudspeakers.

A power amplifier connects a reservoir of energy to the loudspeaker through a type of valve (solid-state or vacuum tube) controlled by the input stage. If the input stage has done a good job of preserving music’s subtle details, textures, timing and phase information, transferring it without loss to the loudspeaker can be accomplished in a few ways: the most efficient is Class D.

The history of Class D amplifiers stretches back to the 1950s, though those early designs—even those into the late 1990s—had much to be desired, sonically. Modern designs capable of high linearity and neutral sound quality weren’t available until the early 2000s, and into late 2015.

There is a lot of misinformation surrounding class D amplifiers. Perhaps the most common is they are digital, which is incorrect. A Class D amplification stage is an analog process, known as Pulse Width Modulation (PWM). Class D amplifiers do switch in on/off fashion, which is likely the reason they wrongly acquired the “digital” moniker.

The Stellar M1200 has a massive power factor corrected power supply and ultra-linear high Wattage power amplification stage, based on the newest ICE Edge technology, designed in Denmark.

The Stellar M1200 provides excellent frequency extremes, low distortion, high efficiency, high damping factor, and a generous and powerful output of 1200 Watts into the most common loudspeaker loads of 4Ω.

Is 1200 Watts too much for my loudspeakers?

No. As mentioned, power amplifiers need not be matched to speakers for fear of overpowering them. Their output wattage is controlled entirely by the preamplifier and user’s volume setting. The advantages of a massively powerful amplifier like the M1200 are headroom and increased linearity for any input signal of any size. The end results are nothing short of breathtaking Regardless of what loudspeakers, the massively powerful nature of the M1200 works well with any loudspeaker, providing huge amounts of headroom and effortless sound quality for even the most demanding orchestral crescendos.

Stellar M1200 Mono Amplifier

Unit Weight27 lbs [12.2 kg] (each) Unit Dimensions17”W x 3.75”H x 12”D (13"D w/connectors)
17”W x 7.5”H x 12”D (Stacked)

Shipping Weight29 lbs [13.15 kg] (each)
Shipping Dimensions22”W x 8”H x 17”D (each) Color OptionsBlack
Silver Vacuum tube type12AU7 Voltage Options
(Factory set only)Japan 100V
North America 120V
Europe/Asia/Australia/New Zealand 230V Mains Power InputsIEC C14 Idle Power Consumption27W Power Factor>0.9 @ rated power 4Ω Accessories IncludedUS (NEMA 5-15P) (all versions)
Schuko (CEE7/7) (230V version)
UK (BS 1363) (230V version) Audio InputsRCA (Unbalanced)
XLR (Balanced) Speaker Outputs Copper base nickel plated binding posts (2 pair) DC Trigger Input 3.5mm 5-15VDC Warranty3 years parts and labor

Signal

Gain30.5dB +/-0.5dB Sensitivity for rated output power2.08V Signal to Noise1kHz@1200 Watts > 112dB Input impedance Unbalanced 50KΩ
Balanced 100KΩ Output Impedance50Hz, 2.8VRMS <0.007Ω Damping factor50Hz. 2.8VRMS
8Ω >1100
4Ω >550 Frequency Response2.8VRMS into 4Ω
10Hz – 20KHz +/- 0.5dB
10Hz – 45KHz +0.1/-3.0dB

THD&IM

1KHz, 1W/4Ω< 0.005% 10-20KHz, 1W/4Ω< 0.01% 1KHz, 150W/4Ω< 0.02%

Output Power

120vac mains, 1kHz, 1% THD 8Ω600W minimum 4Ω1200W minimum 2ΩStable for musical transients