Few spirited e-mail threads are exchanged among the SoundStage! Network’s editorial staff. With so many articles coming out each month that need eyes on them to ensure that they’re squeaky clean for your reading pleasure, I find myself weighing in only when I spot something amiss, or I see a chance to lob a snarky remark at the infallible Jeff Fritz or the Napoleonic Doug Schneider. Recently, however, an objectivist/subjectivist discussion broke out that prominently featured the topic of “bias.” No matter where you are on that continuum, bias is of course unavoidable, and to suggest otherwise would be ignorant.
As I sit here contemplating Constellation Audio’s Inspiration Integrated 1.0 integrated amplifier, the notion of inherent bias lurks at the edge of my consciousness. At $16,500 USD, the Inspiration Integrated 1.0 is one of the least expensive products in Constellation’s four product ranges. Ordinarily, when you drop $16,500 on an electronics component, you expect to be impressed by its big box, provocative visual design, and killer specifications -- all of which adds up to a medley of biases. But the Inspiration 1.0, like all of Constellation’s offerings, looks like a blue-sky concept drawing that was never repeated. It looks like something you might see in a minimalist living room in Architectural Digest -- you know, one of those places where no actual human being actually lives. Closer inspection doesn’t much change this impression. This class-AB design has no built-in DAC or phono stage, and generates 100Wpc into 8 ohms. If I entered this review with any bias, it was of my initial impression of the Integrated 1.0: that it was rather unremarkable. For a reviewer who’s been around a few blocks, that’s as good a starting point as any.
Constellation Audio has been around since 2008, and in that time the California-based electronics manufacturer, founded by the same Australians responsible for Continuum Audio Labs, has launched four product lines. From bottom to top in terms of price, these are the Inspiration, Revelation, Performance, and Reference ranges of models, the last of which tops out with the Hercules II monoblock power amplifier ($190,000/pair). The entry-level Inspiration line has four members: the Stereo 1.0 stereo power amplifier ($12,500), the Preamp 1.0 preamplifier ($11,000), the Mono 1.0 monoblock power amp ($25,000/pair), and the subject of this review, the Integrated 1.0 integrated amplifier. Constellation also makes a pair of phono stages, a DAC, and a standalone power supply.
The Inspiration Stereo 1.0 develops 200 or 400Wpc into a respective 8 or 4 ohms. The Mono 1.0 doubles those values into 400 and 800Wpc, while the Integrated 1.0 halves them, producing 100 or 200Wpc into 8 or 4 ohms, measured using a 1kHz test tone at 1% THD+N. This makes the Integrated 1.0 not exactly a powerhouse -- though Irv Gross, Constellation’s friendly VP of Sales, told me that the amp is stable down to 2 ohms. Ornery speakers aren’t necessarily ruled out.
The Integrated 1.0 measures 17”W x 5.5”H x 19”D and weighs 43 pounds, and its design draws heavily on those of the Stereo 1.0 and Preamp 1.0, as well as on core technologies that Constellation uses throughout its product lines. One of the latter is the company’s minimum-feedback, class-AB, Balanced Bridged amplifier circuit, which uses N-type transistors throughout instead of a combination of N and P types, as is done in many other solid-state designs. Constellation claims a benefit of this practice: the positive and negative halves of an audio signal thus behave identically, to result in perfectly symmetrical output. Every Constellation amplifier model, including the flagship Hercules II monoblock, contains at least one Balanced Bridged module, each of which has eight output devices per channel. The module’s 125W power specification leads me to think that the Integrated 1.0’s spec of 100Wpc into 8 ohms might be conservative. The Integrated 1.0 is biased into class-A for the first couple of watts.
The Integrated 1.0 also makes use of Constellation’s Line Stage Gain Module, a “balanced circuit from two mirror-imaged amplifiers, one for the positive half of the signal and the other for the negative half,” with “hand-matched, ultra-low-noise FETs and servo circuits.” Throw in a linear power supply whose 1400VA transformer is coupled with 100,000μF of capacitance per channel, an analog volume control with a digitally addressed resistive ladder, and a headphone amp that outputs 800mW into 32 ohms, and you have yourself a nice little high-end integrated. Other specs include a frequency response of 10Hz-20kHz, ±0.5dB; total harmonic distortion plus noise of 0.035%, measured at 1kHz when delivering 25W into 8 ohms; an output impedance of 0.125 ohm; and output noise of -84dB, A-weighted.
The Integrated 1.0’s minimalist front panel is headlined by a 432x230-pixel, monochrome touchscreen flanked by machined aluminum dials: Balance on the left, Volume on the right. The touchscreen worked well; five small buttons hidden on the underside of the protruding ledge of the panel that holds the knobs and screen control some of the screen’s functions, including brightness and turnoff time (e.g., always on, turn off after 15 seconds, 1 minute, etc.). The case is milled from aluminum and sandblasted, then anodized, to give it an unusually grippy finish. Subtle design flourishes include two vertical ridges that emerge from the front panel’s surface at its bottom edge, gradually rise in relief as they climb the faceplate, then continue across the top plate until they disappear into that panel’s surface just before reaching its rear edge. All venting is to the sides, through a pair of overlapped plates on each side perforated with quarter-size holes, the positions of the holes staggered so that they don’t quite align. It looks pretty cool. Out back are two pairs each of balanced (XLR) and unbalanced (RCA) input jacks; a USB Type-B port for firmware updates and connection to third-party control systems; an RS-232 port; a 12V trigger; a 1/4” headphone jack; a pair of balanced (XLR) outputs; an IEC power inlet; and pairs of beefy Argento speaker binding posts.
The Integrated 1.0’s aluminum remote control is one of the very best I’ve used. It’s simple and solid yet not too heavy, and its buttons have a satisfyingly “clicky” action. And it lets you turn the amp off and on, which is not always a given. In my experience, good remotes often don’t earn the attention they deserve, despite the fact that most users almost always interact with the remote more than the controls on the component itself. This is a good remote. Nicely done, Constellation.
My review sample of the Inspiration Integrated 1.0 arrived rather worse for wear. Its shipping carton had clearly been dropped from an uncomfortable height, which had bent the bottom plate where it supports the transformer -- that part of the plate was no longer perfectly flush with the front panel. But the amp seemed otherwise unfazed, and worked perfectly right out of the box. At first I hooked it up to Mytek’s Brooklyn DAC+ digital-to-analog converter via the Constellation’s balanced and unbalanced inputs, to confirm that both worked. But because the Constellation is fully balanced from input to output, I quickly opted to use balanced connection, via Nordost Blue Heaven balanced interconnects. Later, I swapped out the little Mytek for dCS’s Bartók DAC, also connected to the Integrated 1.0’s XLR inputs. Loudspeakers included Xavian’s Classic Quarta and Focal’s Diablo Utopia Colour Evo monitors, both in for review, as well as my own two pairs of KEFs: Reference 3 towers and LS50 monitors.
To stream local content and Tidal HiFi via a DH Labs USB link, I connected my music server, based on an Intel NUC computer, to the Mytek and dCS DACs. I also plugged the dCS into my network with a generic Ethernet cable, and my Google Chromecast Audio to both DACs with a generic optical (TosLink) link, which let me wirelessly stream music from Tidal and Spotify directly to my system via my Apple iPhone 11 Pro smartphone. The Integrated 1.0 and DACs were connected to my Emotiva CMX-2 power conditioner with Nordost Blue Heaven power cords. Speaker cables were AudioQuest’s Rocket 33.
Another bias: The more I review high-end, class-AB integrated amplifiers, the harder time I have telling them apart. That’s in no way a criticism of the topology or the manufacturers who base their designs on it: I’ve owned only class-AB integrateds, which I prefer over all other varieties. I think I have trouble telling them apart because these days all class-AB amps sound really good; the differences are mainly in component cost, design philosophy, and features. It’s not that they all sound identical to me, but that, in my experience, the differences between one high-end class-AB integrated and another can often be minute.
That thought occurred to me when I spent an afternoon listening to film soundtracks through the dCS Bartók DAC, the Constellation Inspiration Integrated 1.0, and my KEF Reference 3 tower speakers. While the great majority of class-AB integrated amps sound quite neutral to me, I was having a hard time hearing any sonic signature from the Constellation. It was fascinating to hear film scores by Hans Zimmer and Max Richter sound so utterly balanced. I recently wrote the same words about Simaudio’s Moon 700i v2 integrated amplifier ($14,000), though I noted that the Simaudio consistently sounded more spacious than the other high-end, class-AB amps I compared it to: Hegel Music Systems’ H590 integrated-DAC ($11,000) and Gryphon Audio Designs’ Diablo 300 integrated ($16,000).
With “Mad Rush,” from Philip Glass’s Solo Piano (16-bit/44.1kHz FLAC, CBS/Tidal), it was remarkable how I was able to check every audiophile box. Glass’s repetitive, minimalist theme danced in front of me with an intoxicating blend of accuracy and smoothness, and nary a hint of harshness or bite in the sound of his piano. The depth of the soundstage extended well past my room’s front wall, and its width past the outer side panels of my KEF floorstanders. Glass’s nimbleness on the ivories was on full display in my room, and in no way was the weight or distinction of individual keystrokes abbreviated. The imaging was superb -- I could easily track his fortissimo runs up and down the keyboard -- yet the Integrated 1.0’s articulation and spaciousness never called attention to themselves. The elusiveness of any sound of the Constellation’s own meant that, whether I played this 1989 recording or a far more recent selection by Jóhann Jóhannsson, I got the same result: everything sounded accurate, linear, fundamentally right -- dare I say, perfect? Those who, like me, love dynamics and top-end sparkle will be plenty satisfied -- as will those whose tastes veer toward a fuller, more analog sound, which the Integrated 1.0 also delivered in spades.
I often find that certain components drive me toward certain corners of my music collection. With the Integrated 1.0, I found myself listening to more singer-songwriters than usual. I suspect that was because the Constellation sounded so smooth, rich, and natural through the midrange that it seemed to almost slow down the music, which perfectly suited the slow, deliberate pace of “Cold Heart,” from Norah Jones’s Come Away with Me (24/192 MQA, Blue Note/Tidal). Her opening lines sounded almost lush in their palpability and texture. It was easy to imagine the ambiance of a thin, jazz club-like haze between me and Jones’s piano as she seductively crooned into her mike. After playing the 24/192 MQA version on Tidal, I tried the original 16/44.1 version (FLAC, Blue Note/Tidal), to listen for differences. Sure enough, as I switched back and forth between the two versions at the same volume level, Jones’s voice at 16/44.1 sounded a touch lighter and airier, with a greater emphasis of sibilants that sounded slightly less refined than the buttery-smooth MQA version. Her piano, too, had greater urgency. Even then, however, the combination of the Constellation Integrated 1.0, dCS Bartók DAC, and KEF Reference 3s produced an eminently supple sound that I could listen to for hours on end -- and did. I never experienced the dreaded listening fatigue, and in making that possible, the Integrated 1.0 gave up precious little in dynamics.
I’m guessing that most owners of Constellation Audio gear won’t be serving their five-figure electronics Nine Inch Nails at seriously high volumes. I put on the 2010 remastering of the band’s first album, Pretty Hate Machine (16/44.1 FLAC, TVT/Tidal). Bandleader Trent Reznor is renowned for his fanatical attention to production quality, and I was shocked by how clean this 1989 recording sounded. “Head Like a Hole” was downright fantastic, Reznor’s voice sounding far more refined and polished than any late-1980s recording ought to as the Constellation conjured up a healthy dollop of air for this atmospheric cut. The background drums sounded metallic and distant -- very period-appropriate -- and when I increased the volume even more they scaled perfectly, especially the kick drum. Unlike with the Norah Jones cut, which sounded dark and intimate, the sound of “Head Like a Hole” was far more expansive, again highlighting the Integrated 1.0’s uncanny ability to let a recording speak for itself. As I said, I suspect that Constellation’s spec of the Integrated 1.0’s power output is conservative -- despite administering repeated hammerings of loud music at high volumes, I heard no compression or distortion of any kind. Nor was the Integrated 1.0 ever more than slightly warm to the touch, even when sandwiched between other components on my rack.
If you’re into Australian busker music -- and who isn’t? -- I suggest Tones and I, aka Toni Watson. Her single “Dance Monkey” (24/48 MQA, Elektra/Tidal) went platinum in the US in 2019, and its seriously catchy hook sounded phenomenal with the Constellation in my system. This tasteless millennial listens to a lot of trashy pop mastered by engineers (in this case, Andrei Eremin) who clearly do not have $40,000+ hi-fi systems in mind as they place the finishing touches on fire new singles. Indeed, many pop musicians these days go for a hyperclean, unnaturally stark sound that probably sounds reasonable through earbuds, but doesn’t ring naturally through a pair of big KEF speakers. Artificial, digital-sounding, whatever you call it, “Dance Monkey” is a perfect example of this sort of mastering, and I kinda dig it. Through the Integrated 1.0, the boosted reverb on Watson made her voice really pop from the center of the soundstage, and the bass line had copious drive and impact. It was all very vibrant and high-contrast -- more evidence that the Constellation was something of an aural chameleon.
One of the nice things about the Integrated 1.0 was its low noise floor; it’s one of the quieter class-AB amps I’ve heard, and definitely quieter than my reference integrated, the Hegel H590. This revealed itself with such sweeping pieces as Arvo Pärt’s De Profundis, for male chorus, percussion, and organ, as performed by the male choir Theatre of Voices under the direction of featured baritone Paul Hillier (16/44.1 FLAC, Harmonia Mundi/Tidal). The men’s voices resounded in the enormous chapel of St. Stephen’s Church, in Belvedere, California, the Integrated 1.0’s terrific transparency letting me hear nuances in the organ part at rear left of the soundstage, and its interaction with the venue’s acoustic. And unlike some other amps, whose lack of noise and distortion can sound more stark and forward, the Constellation’s smooth but not necessarily laid-back sound made it an easy listening companion. I listened to De Profundis several times in a row, just to focus on different aspects of the performance.
The headphone amplifier of my review sample was functional, but had the highest noise floor of any headphone amp I’ve ever used. Wanting to verify that the noise wasn’t dependent on the source or the headphones, I tried all four inputs, balanced and unbalanced, with no music playing, and three pairs of headphones: Grado’s 32-ohm SR125 open-back cans, NAD’s 32-ohm Viso HP50 closed-back ’phones, and PSB’s 16-ohm M4U 4 in-ears. The result was always the same. I sent the unit back to Constellation for testing and they verified that the headphone amp was not damaged. Rather, they said, it was designed for use with high-impedance headphones, whereas all of the ’phones that I used were of the low-impedance variety. Just to be clear, then, inexpensive headphones and earphones that can be driven by most any smartphone are effectively unusable with this five-figure integrated amp.
As good as the Constellation Inspiration Integrated 1.0 was, at $16,500 it has an awful lot of competitors, chief among them Simaudio’s Moon 700i v2 ($14,000). In many ways, the 700i v2 seems to offer more for less: it’s fancier (to some, more garish), 19 pounds heavier, and its ten-year warranty more than triples the Constellation’s three years. The 700i v2 also offers nearly twice the power, generating 175 or 350Wpc into 8 or 4 ohms, respectively, the first 5W in class-A. The Sim and Constellation trade blows on the connectivity front -- or rear, actually. The 700i v2 offers two more pairs of unbalanced inputs, unbalanced outputs, and a tape monitor input and output. The Integrated 1.0, meanwhile, has an extra pair of balanced inputs, balanced outputs, and that built-in headphone amp.
Sonically it was a near wash. Each amp was an excellent example of what, in 2020, a top-flight class-AB integrated amp should look, feel, and sound like. Each had an extremely transparent sound that let me hear deeply into recordings of all genres. And each of those sounds was superbly neutral -- in tech terms, each had a ruler-flat frequency response.
There were two subtle differences. The Simaudio sounded a little airier and more extended in the treble, which made its sound seem bigger and, seemingly (though not actually), more transparent. By fine margins, the Constellation traded that spacious top end for a touch of smoothness through the mids that lent it a more robust tangibility.
But depending on the music I played, I preferred the Constellation. Then the Simaudio. And then the Constellation again. As I said: sonically, a near wash.
Constellation Audio’s Inspiration Integrated 1.0 is everything you’d want in a fashion-forward, nearly state-of-the-art integrated amplifier. Its inspired industrial design will be appealing to many, as will its remote control, one of the very best I’ve used. But it’s the Integrated 1.0’s sound that places it in the upper echelon of integrated amplifiers I’ve spent time with. It serves up equal and healthy helpings of clarity, smoothness, linearity, and dynamics without sacrificing anything along the way. For that reason, it proved one of the more difficult products to review of my experience: it gave me effectively nothing to glom on to -- to my thinking, an emphatically good thing.
For those, like me, who can’t comprehend the appeal of big separates, the Integrated 1.0 is a convenient way to get a substantial taste of the Constellation sound without having to pony up tens of thousands of dollars more. If their entry-level product sounds this good, how much better can it get? Ignorance is bliss.
. . . Hans Wetzel
- Speakers -- Focal Diablo Utopia Colour Evo; KEF LS50 and Reference 3; Xavian Classic Quarta
- Headphones -- Grado SR125, NAD Viso HP50, PSB M4U 4
- Integrated amplifiers -- Hegel Music Systems H590, Simaudio Moon 700i v2
- Digital-to-analog converters -- dCS Bartók, Mytek Brooklyn DAC+
- Sources -- Intel NUC computer running Roon, Tidal HiFi; Apple iPhone 11 Pro smartphone
- Speaker cables -- AudioQuest Rocket 33, DH Labs Q-10 Signature, Dynamique Audio Caparo
- Analog interconnects -- Dynamique Audio Shadow (unbalanced, RCA), Nordost Blue Heaven LS (balanced, XLR)
- Digital link -- DH Labs Silver Sonic (USB)
- Power conditioner -- Emotiva CMX-2
Constellation Audio Inspiration Integrated 1.0 Integrated Amplifier
Price: $16,500 USD.
Warranty: Three years parts and labor.
Suite 1, Level 6
580 St Kilda Road
Melbourne, Victoria 3004
3533 Old Conejo Road, Suite 107
Newbury Park, CA 91320
Phone: (805) 201-2610