Altair II



Sound quality.

Consider Altair II a collaborative effort. It began with the original Altair, created by Constellation Audio’s “dream team” of the world’s best audio engineers and industrial designers. Our engineers then refined these original concepts using feedback from our dealers and customers. The result is a product with a more user-friendly interface, yet that retains the same sound quality as the original Altair, acclaimed by a leading audio magazine as setting a new standard “in virtually every sonic and musical criterion.”

Machined remote control

Precision and dynamics.

With its innovative circuitry and incomparable build quality, Altair II achieves something no other preamp can: the musicality of classic tube preamps with precision and dynamics matched by no other solid-state preamp. Only upon hearing the Altair II can one appreciate the musical experience it delivers.

Line Stage Gain Module

We build the Line Stage Gain Module’s balanced circuit from two mirror-imaged amplifiers, one for the positive half of the signal and the other for the negative half. Through the use of hand-matched, ultra-low-noise FETs and servo circuits, our engineers have achieved an essentially perfect balance between the positive and negative halves of the audio signal.

Fully balanced circuitry

Because the Line Stage Gain Module’s circuit is fully complementary, comprising two identical circuits, it automatically cancels incoming noise and interference while increasing slew rate and frequency response. As a result, Altair II achieves an extraordinary 200-kilohertz bandwidth.

Machined remote control

Simple, elegant remote control

The new machined aluminum infrared remote control provides a gratifying, friendly interface with Altair II. The remote’s soft leather cladding feels comfortable in the hand, and also provides a slip-resistant grip. All of Altair II’s most commonly used functions can be controlled from the remote.

User-friendly front touchscreen

Altair II’s front touchscreen accesses all of the preamp’s advanced functions, including input configuration and all other setup parameters. Large, high-contrast fonts allow the display to be read from across a room.

Incomparable mechanical isolation

Altair II’s audio circuits are double-isolated from vibration. Each Line Stage Gain Module is mounted on a sandwich of an isolating polymer layer between two stainless steel sheets. An elastomeric suspension in turn supports this platform. Highly flexible, custom-made wiring prevents any vibration on the chassis from reaching the “floated” circuit boards. The sheer mass of the Altair II chassis and internal assembly also helps damp vibration.

Home theater bypass mode

Through the front touchscreen, one of Altair II’s inputs may be configured for home theater bypass. This mode allows the left and right channels from a surround-sound processor to pass through Altair II, permitting the same left/right speakers and amplifiers to be used for two-channel or multichannel reproduction without having to make volume adjustments. Switching to any other input restores two-channel sound.

Nearly impermeable shielding

Key circuit modules inside Altair II are isolated from the others to reduce interference to the lowest possible levels. A machined aluminum shield protects each individual Line Stage Gain Module, while formed aluminum enclosures shield the control circuits. The thick walls of the machined aluminum chassis provide additional shielding against outside interference.

Machined solid aluminum chassis

In order to block 50/60 Hertz electromagnetic interference from household circuits, we encase Altair II’s inner workings in an enclosure machined from solid billets of aluminum to a minimum wall thickness of 8.2mm. These thick walls cannot resonate or vibrate as a sheet metal enclosure can.

Constellation Direct balanced interface

Owners of Constellation Audio’s Hercules and Centaur amplifiers can experience an even higher level of quality from Altair II through our Constellation Direct interface, which bypasses the input module of the amplifiers to reduce the number of gain stages in the signal chain. This reduces noise and improves reproduction of musical detail.

Triple-transformer power supply

Altair II’s power supply incorporates three separate R-core transformers, one for left channel analog audio, one for right channel analog audio, and one for control circuitry. The power supply’s machined aluminum enclosure shields the audio section of Altair II from the transformers’ electromagnetic energy. Custom-extruded PCOCC cables tipped with aerospace-type Hypertronics connectors carry the separate the three separate power feeds to the Altair II main chassis.

Optically controlled resistors for volume control

An array of 48 optically controlled resistors provides far more precision and sonically transparent volume control than even the highest-quality potentiometers can. A temperature-compensated tracking circuit that maintains ideal signal balance in all conditions. Because the optically controlled resistors are electrically isolated from the control circuits, they are as sonically benign and musically transparent as a conventional high-quality resistor.

4 XLR stereo, 4 RCA stereo
2 XLR stereo, 2 RCA stereo
Output noise:
<20 uV dB, 20 Hz - 20 kHz
0.001%, 20 Hz - 20 kHz @ 2V out, RI >10 K
0.1%, 20 Hz - 20 kHz @ 10V out, RI >10 K
Frequency response:
10 Hz to 200 kHz, +/- 0.5 dB
Input impedance (balanced):
200 K
Input impedance (single-ended):
100 K
Output impedance:
< 50 ohm
Volume control resolution:
0.1, 0.5, or 1 dB; user-selectable
Recording outputs:
1 XLR stereo, 1 RCA stereo
84 lbs / 38.2 kg, line stage
26.2 lbs / 11.4 kg, power supply
Dimensions (W x H x D):
17.5 x 5.53 x 14.8 in (whd), line stage
44.5 x 14 x 37.6 cm (whd), line stage
17.5 x 2.82 x 14.5 in (whd), power supply
44.5 x 7.2 x 36.8 cm (whd), power supply

The Absolute Sound

Golden Ear
Award 2016

“Constellation Audio took what was already the highest resolution and most transparent solid-state electronics I’ve heard… and vaulted them to a new level of performance in the Series II.”

The Absolute Sound

Editors' Choice
Award 2019

Constellation Audio received a number of Editors’ Choice Awards for 2019 from The Absolute Sound.

The Absolute Beat

Jimmy Awards

” Constellation Audio’s Dream Team of designers consists of stars in the audio firmament. Among others, John Curl, Bascom King, Peter Madnick, and the late James Bongiorno have contributed to various aspects of Constellation product design. The legendary Irv Gross handles sales and marketing. “

The Absolute Sound

Product of the
Year Award

Reference Series Altair II Preamplifier and Hercules II Amplifier have been awarded the Absolute Sound 2015 Product of the Year award.

The Absolute Sound

The Absolute
Sound Editors
Choice Awards

Constellation Audio won multiple awards this year in The Absolute Sounds Editors’ Choice Awards 2022.

The Absolute Sound

Stereo Sound
Grand Prix 2014

Stereo Sound Grand Prix 2014 Winners:
Hercules II Power Amplifier and Altair II Line Stage

Altair II;
“A system that delivers such an incredible sound that you become lost within the music.”
“One of the best preamplifiers existing today.

Hercules II
“A stunning performance level that outstrips the original.”
“A product that will leave you yearning for it all the more.

The Absolute Sound

The Absolute
Sound - Editor's
Choice Awards

Editors’ Choice 2012

Hercules and Altair have been awarded the Absolute Sound 2012 Editors’ Choice award .

The Absolute Sound

Absolute Sound
2011 - Product
of the Year

Hercules and Altair have been awarded the Absolute Sound 2011 Product of the Year award.

The Absolute Sound

TAS Editors
Choice Awards

The Absolute Sound granted a number of our components with their Editors Choice Award 2020, including:

Altair II. Argo. Centaur II, Hercules II/Hercules II Stereo, Inspiration 1.0, Inspiration Mono 1.0, Inspiration Preamp 1.0, Inspiration Stereo 1.0, Perseus, Andromeda, Pictor, Taurus Stereo, and Taurus Mono Amplifier.

The Absolute Sound

The Absolute
Sound - Editor's
Choice 2016

Inspiration STEREO 1.0, Inspiration MONO 1.0, Inspiration PREAMP 1.0, Centaur Stereo, Argo, Perseus, Virgo III, Altair II, Hercules II Mono have been awarded the Absolute Sound 2015 Editor’s Choice award.

The Absolute Sound

The Absolute
Sound Editors
Choice Awards

Constellation Audio won multiple awards this year in The Absolute Sounds Editors’ Choice Awards 2021.