Hardware Reviews

Constellation Audio Inspiration Preamp 1.0/ Mono 1.0


I have long been a fan of the sculpted forms produced by the Neal Feay company, Resolution Audio’s beautiful Cantata first brought this Californian metal worker to my attention but it was Constellation Audio that showed just how finely they can machine aluminium, with creases that fade to nothing like a piece of silk. It should come as no surprise perhaps to discover that Alex Rasmussen, the guy behind the Constellation designs is the president of Neal Feay, it would take someone deeply embedded in the computer aided design and manufacturing world to understand how much more could be done with the technology than is usually attempted.

It did the trick and drew me to Constellation, a company that’s unusual in that it pools the talents of a range of industry experts to produce electronics that in my experience sound at least as good as they look. Those experts include Peter Madnick of Audio Alchemy, phono stage guru John Curl and digital audio maverick Demian Martin. The people who gathered the Constellation team also brought the Continuum turntables to the market, so it’s safe to say that they know a thing or two about high end audio.


preamp 1.0 2 display


The Inspiration range is Constellation’s entry level, the casework is still beautifully sculpted in matte aluminium but it’s not quite as luxurious as the Performance and Reference models and the individual components are not as difficult to move, a bonus in my book. There is even an integrated ampilifer in the Inspiration range that looks very similar to the Preamplifier 1.0. The latter is a fully balanced, line stage with six inputs, three on XLR the rest via RCA, there is also a USB input on the back but it’s for control purposes, there is no digital to analogue converter in the box. Outputs are available in both flavours and two of each should you feel the urge to run four power amps.

It has a touch sensitive LCD display and is supplied with a suitably crafted remote handset to match. This proved to be the best thing to change level with as the rotary on the preamp itself is geared to work slowly, which is nice for fine volume changes but less good if you want big jumps. Each input remains at the volume level it was last used with so there’s not need to compensate for source variations, which is a nice touch.


constellation inspiration preamp rear


Under the lid the Inspiration Preamp has a lot of similarities to the Altair II and Virgo II in the upper echelons of the company’s catalogue, it is based on the same circuit and shares many of the same parts. It’s interesting and encouraging to note that the circuit boards are isolated with compliant mountings, a technique that you find in the top Naim electronics but which is not common even in the high end. The power supply is heavily shielded to give the audio signal a quiet electrical environment, and uses separate R-core transformers for each channel – this is a fully dual mono line stage after all – plus a third transformer for the control circuits.

The Inspiration power amplifier comes in stereo and mono variants, the stereo being the same price as one monoblock. At a ‘mere’ 36 kilos these are the lightest power amps that Constellation makes, which gives you some idea of the situation further up the line. But the Mono 1.0 is no lightweight in any respect, it is specified to deliver 400 Watts into eight Ohms and twice that into four from a balanced bridged output stage. This topology means that Constellation only uses N-type output devices rather than N and P-type pairs as found in unbridged designs, the purpose being to avoid differences in transistors that can undermine transparency, timing etc. On the back panel are RCA and XLR input sockets alongside two pairs of cable terminals for spade or bare wire connections. You’ll notice that there are two XLRs, one is simply marked ‘balanced’ while the other is called ‘direct’. This is because the balanced connection takes the signal through an extra stage of gain compared to direct, both deliver the same amount of power but you need to turn the volume up further with the direct input.


constellation inspiration mono rear


Comparing the two inputs makes it pretty clear that ‘direct’ is the way to go. When I first reviewed a Constellation pre/power (Virgo and Centaur in 2013) I found that I preferred the balanced input, the extra dynamics and pace it delivered via B&W 802 Diamond loudspeakers was captivating. This time around I happened to use the new and quite significantly revised 802D that has replaced that speaker for much of the listening and kept coming back to the direct input. The results were essentially the same, direct gives greater subtlety and insight while balanced produces a more visceral experience, so the new 802s are clearly more revealing and perhaps my taste for volume has calmed because the reduction in perceived distortion using the direct input was easily the winner.

The combination of Inspiration amplifiers delivered on of the most subtle and revealing results I have had the pleasure of hearing, initially it seems unduly soft but after a short while it becomes clear that this is because there is so much less distortion than most amplifiers. There is a tendency to turn the volume up higher as a result which is fine until you put on something with real dynamic range and find the drive units in your lap. OK, it’s not that extreme but there is a direct connection between perceived volume and distortion, the lower the latter the more level you can comfortably enjoy. In fact it’s not like high volume in the usual sense at all for this reason, it’s just more realistic music. It’s a visceral sound all right but the cleanest sound you are likely to encounter, and thus takes a bit of getting used to. Not to mention a lot of coming down from once it’s gone and you have to live with regular amps again, all of which sound bright, grainy and opaque.


constellation inspiration mono intern


What does this do for the music, well it lets it expand out into the room and take up a physical presence that’s underpinned by the most natural tonal balance I’ve heard from solid state electronics in a long time. The transparency on tap means that all the nimbleness, solidity and depth of the music is revealed alongside depth of image that’s breathtaking. Inevitably the Inspiration trio produce the most convincing music with the best recordings, and when these are of acoustic instruments all the better. Arvo Pärt’s ‘Fratres for cello and piano’ is a good example, an ECM recording that is extremely quiet as these amps make abundantly clear, the cello is placed well back in the stage to begin with but comes forward when the volume rises, it’s distinctive timbre evoking tragedy in true Pärt style and its reverb sounding totally real and natural. You realise after a while that there is no sense that speakers are producing the sound, it just seems to be there in front of you, unrelated to the actual source. Credit due to the speakers as well of course but they can’t do this so convincingly with most amplifiers. The other instrument in this piece, the piano, is also convincing because it has such a strong sense of gravitas and body, this amplifier has huge power but does not call attention to itself which is difficult trick to pull off.

This is also a very revealing, even analytical amplifier that manages to present every facet of the recording without losing hold of the musical message. All sorts of subtle details appear in familiar pieces of music, Laura Marling’s ‘Friends’ has a strange phasey character applied to all the instruments but not the voice. Giving it a psych rock feel that is normally only hinted at. The activities of bass and drums on ZZ Top’s ‘Enjoy and Get It On’ are exposed to full effect as well, normally they provide a funky blues drive for the guitar and vox but the Constellations expose just what goes into creating that vibe. With a Rega RP10 turntable, Aphelion cartridge and Music First Classic MM phono amp 632, you get a sense of limitless headroom. With a source this clean there is no apparent distortion and tendency to go on pushing the volume further than normal. The idea that you might need more power seems bizarre, yet this is the least powerful amplifier that Constellation makes. Which is a relative state of affairs of course, it’s more powerful than most even at this price point. And a lot more subtle too, I imagine that some might find it a shade soft, certainly going over to the more affordable amps I usually use makes them seem hard edged. But it’s the lack of grain in the Monos that makes them so transparent, that makes string sections so natural yet also delivers the power and muscle of electronic music like Kraftwerk and Infected Mushroom.


amp 1.0


They work extremely well with quiet music too, sensitivity to micro dynamics – the change in level from one note to the next – is very high indeed, the music offering up new layers of subtlety as a result. Listening becomes a deep immersion experience with these Constellations, they open up music that you think you know and expose all the nuances. But it’s also a lot of fun playing heavy tracks, the monster bass of modern German dub (Burnt Friedman and Jaki Liebezeit’s Secret Rhythms) is unusually painless, most amps struggle to control the depth and magnitude of low end on this, these do not. Here it’s clean, clear and more musical than it’s sounded in a long while. I read a review of this album saying that the rhythms were perhaps a little too secret, but in fact they are just too heavy for most systems to deliver in coherent fashion.

The list of revelations goes on for several pages in my notebook, these amplifiers keep you coming back for more late into the night. I’m still not quite sure why the direct input sounded so much better this time around, but it certainly does. It’s a pity that you can’t access this mode via the single ended connection but I did discover that you can use a single ended output with a cable that has an XLR at the right end. However for best results stick with balanced from Preamp 1.0 to Mono 1.0s and you will discover just what it means to be totally in thrall to the music.


Preamp 1.0
Type: One box, solid state, fully balanced line-stage preamplifier
Analogue inputs: 3 balanced via XLR, 3 single-ended inputs via RCA
Analogue outputs: 2 pairs balanced via XLR, 2 pairs single-ended via RCA
Input impedance: balanced 20 kOhms, unbalanced 10kOhms
Output impedance: <50 Ohms
Frequency response: 10Hz – 100 kHz ±0.5dB
Distortion: <0.001%, 20 Hz – 20 kHz @ 2V out, <0.1%, 20 Hz – 20 kHz @ 10V out
Signal to Noise Ratio: >-105 dB, A-weighted
Dimensions (HxWxD): 133 x 432 x 381mm
Weight: 11.3kg

Mono 1.0
Type: solid state mono power amplifier.
Analogue inputs: direct XLR, balanced XLR, single ended RCA
Analogue outputs: 2 pairs metal binding posts
Power output: 400W @ 8 Ohms, 800W @ 4 Ohms
Frequency response: 10Hz – 80 kHz ±0.5dB
Gain: 4dB Ddirect, 26 dB balanced & RCA
Distortion THD+N (1 kHz @ up to 90% of rated power): <0.05%
Signal to Noise Ratio: >-95 dB, A-weighted
Dimensions (HxWxD): 216 x 432 x 483mm
Weight: 36.3kg

Price when tested:
Preamp 1.0 £11,998
Mono 1.0 £12,998 each
Manufacturer Details:

Constellation Audio


Preamplifier and monoblock power amplifiers


Jason Kennedy

Distributor Details:

Absolute Sounds
T: +44 208 971 39 00

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