A Bookshelf Amp?

SX25i Integrated AmplifierWith the measurements of 216mm x 58mm x 192mm (8.5” x 2.3” x 7.6”) this Perreaux SX25i integrated amplifier is above all - NOT A MACHO! So the idea for above picture came quite easy – I would not want to miss this motive, simply too close is the association "pocket amp".

Not only the measurements, but also the power of the Perreaux SX25i with it’s 25 watt into 8 Ohm, don't really show this amp as a “heavyweight”. So this amp might not deliver enough punch to fill big lofts with sound, but smaller up to medium-sized rooms will rarely need more power. Only if they use speakers with a very low degree of efficiency, which would fulminate too much of the little power this nice amp delivers. A medium-sized room with a pair of sensitive compact speakers is my idea of a perfect ambience for this little Perreaux. Maybe the “library room”?

Now seriously, respect to the Perreaux engineers. Not only that they show their bare, cold shoulder to the so called REAL HIGH END guys, but also a more design orientated audience will find this little amp very "chic" – although some of them will be surprised by the lack of features. Exactly one source can be connected to this Perreaux. That’s it. Okay, the volume can be controlled but that’s about it with the tribute to modern times. Bass, treble or balance, nope. A remote? Don’t be so lazy. iPod dock? Gee, we are doing hi-fi here guys! In general I find that very attractive, but at least a second source input would not have been too much of decadence. What if I would like to hook up a tuner next to the CD player?

SX25i Integrated Amplifier InputAnd then, dear Perreaux engineers, why is there an unbalanced line output on a product such as this? Are you real hi-fi fundamentalists, or what…

Perreaux is a New Zealand based high-end audio brand, producing high-end audio equipment for more than 30 years now. In Germany Mr. Joerg Henning Reinelt – head of Expolinear – shows responsible for the marketing since two years.

Product line of Perreaux

1. Prisma series – One preamp and two differently powered stereo power amps are available in this line as well as mono-blocks, a 6-channel power amp, an integrated amp and a CD player. Prices are between 3.000 and 4.000 euros (excluding the 6-channel power amp which is 5.400 euros).

2. Radiance series – This line includes just one product. The state of the art integrated amplifier R200i. 6.900 euro.

3. Silhouette series – With 8 different components this is by far the line covering the widest range. Next to a CD player and a D/A converter, there are six different components within the line-up, an MM/MC phono pre, a headphone amp, a line stage buffer, a passive preamp, as well as mono-blocks and our test item the SX25i integrated amplifier (798 euros). The prices of these components are between 648 euros for the headphone amp and 1.400 for the CD player.

The special characteristic of the Silhouette line is the fact that all components have the same very compact design. From the engineering side – so Perreaux – all components benefit from long experience the company achieved with their high-end lines and offering a reasonably priced entry into the hi-fi world of the New Zealand company at the same time. Let’s get back to our test amp.

Features and Tech Specs

SX25i Integrated Amplifier RearLike mentioned above, there is only one source input, which eliminates a source input switch automatically. The pre-amplified signal can be piped out through the line out (RCA unbalanced), in addition there is a pair of speaker binding posts on the back side of course. Although there is not much space here, due to the size of the amp, the speaker binding posts are easy to reach and use, thanks to an offset of the posts.

Like one can see on the picture, the power switch can be found on the back side of the SX25i. Maybe some of you might complain now, but with a power consumption of 10 watts, when in idle state, the switch will have to be used only once anyway. Your ecological conscience won't leave you sleepless.

SX25i Integrated Amplifier FrontBack to the front panel, the volume knob can be found on the right side, on the left side there is the countersunk logo and a blue LED signals “on”. That’s it.

The power is 25 watts with 8 ohm and 35 watts with 4 ohm. A 98VA toroidal transformer, as well as a whopping 13,200 microfarad capacity are supposed to ensure an ample power supply and a realistic dynamic behaviour. Well, the hi-fi machos between you might laugh now… for a reason? Well, “white papers” and “listening rooms” are sometimes two pair of shoes. Let's see...

Well the kiwis claim to use an “ultra-short signal path” within their SX25i – a quick view inside the amp makes this very clear and trustworthy from the optical paint of view. There is no way of building up long signal paths within this housing.


Perreaux positions the SX25i very clearly as “high-end for the office” or more widely spoken “very suitable for a good second system”. We didn’t let us “wedge in” by this claim and used this baby with speakers that were supposed to be two shoe sizes bigger. We just wanted to know where the limits of this amp are. Honestly, an experiment with partially very perplexing results. More later.

Well, indeed, the right league of speakers for this amp should be compact 2-way systems. The combination Perreaux SX25i / Spendor S3/5 were the starters for our test.

With 84dB, the degree of efficiency of the little Spendor speakers is not overwhelming – and then driven by this small Perreaux? It works, for most situations it is loud enough, even if the max level is limited, of course. That being said, quite a bit above the usual room volume is possible though. I would not recommend to crank it up all the way though – the sound quality really suffers – 3/4 should be maximum.

Within normal levels two things come to my mind instantly.

1. Quite kinky, this little Perreaux.
2. Projection, clarity and volume is sitting on wide shoulders… not bad.

Joe Jackson - Big WorldSaying in little more precise words I mean: Looking at the dynamics, especially the fine dynamics, this little SX25i is really good. Of course, extreme level amplitudes are not it’s strength but someone who is expecting something like “I look good and I can play music as well” will be pleasantly surprised. Not slowly and not hesitant – the Perreaux delivers fully and joyful, no matter if guitar, percussion or something else. If the music gains speed, the SX25i delivers easily. The playback is not blurry or washed out or even unclear. Does anyone remember “Survival”, track 10 on Joe Jackson’s album “Big World”? Speedy piece of music and the SX25i delivers full on.

Another thing is the volumetric distribution within the room: Horizontally I have no reason to complain at all. The stage is wide open, the instruments don’t wander around nor do they jam together in the middle of the room, if you increase the volume. The Perreaux makes it easy to locate the instruments in the room. Honestly, I was surprised how precise the SX25i places it’s hits. One thing though, the bass is a little thin. That doesn’t mean there is none, but there is not as much as I hoped. In addition, the available bass concentrates more or less towards the middle of the room. Well the little Spendor is (in my opinion) surely not a 3D projector, so it has to be seen how the Perreaux SX25i delivers with different speakers.

And tonal? Well the deep bass can’t be analyzed with this set of speakers nor can ultrasound. The rest though shows pleasantly unobtrusive, meaning that nothing obtrudes in an improper way, no unanticipated highlight on the one hand but surely no weak points on the other hand. All-in-all everything is there where it belongs. Well balanced and harmonious.

Nik Bärtsch’s Ronin - REATo be able to test the Perreaux a little better, another set of speakers will be needed, a set of speakers with more potential: Volent Paragon VL2. 2-way compact speakers again but playing within a totally different league than the Spendors (price wise as well – three times as expensive). To get an idea about ability to render the bass properly, I put in Nik Bärtsch’s Ronin album “REA” it play on track 1 and off we go. My dear lord, this little beast is not shy at all, was the first thought that struck my mind. Rhythmic, fast and full of impulse, that is how “Modul 27” is going to be placed into the room. And what a volume? The rendering quality of the bass adds to this impression. Juicy and with lots of fun – yeah that is the right description. Well, a harder texture of the lower octaves floats through my mind – m h it is a little soft but on the other side the range between upper-bass and lower-mids gets rendered perfectly.

Did I complain about a missing volume level at all? Well I guess my neighbours won’t be able to understand that… Seriously: I do not need more volume at the moment, the volume the Perreaux delivers is plenty. Well maybe it is the combination of the SX25i and the Volent VL2 with its slightly better degree of efficiency. That may be – but I rather think that it is the “fat tonal mixture” of this duo (Perreaux SX25i and Volent VL2) that is responsible for the punch. Subjective it just sounds louder because the acoustic pattern is very agile and at the same time bass has a lot of punch. In addition this counteracts the tendency of the Volent to become very hard when reaching high levels. So the slight weakness of the Perreaux – a hint of too much softness in the bass – becomes a good mixture with the Volent. That really shows what this little amp can accomplish when combined with real good speaker. Well a whole lot!

SX25i Integrated Amplifier InsideThe high frequencies render with a lot of detail, open and without annoying artifacts – well not microscopically clear – but in this class far more than just O.K. If there is something I can complain about a bit then it would be the upper-mids. Vocals sometimes seem to have the tendency to be rendered too rough and to prominent, horns sometimes sound too prominent as well and a little bit too metallic, guitars can sound obtrusive from time to time. Well, of course this has to take into account the quality of each individual recording and of the volume level when listening to these recordings. So maybe this characteristic is exactly the reason for the vividness of our little Perreaux SX25i. Well, but the tendency is definitely there. Maybe this is the sole significant point of critic of the SX25i. Missing sovereignty, missing maximum level and very hard texture of low bass. Well, but who demands these attributes in a class like this and therefore from our candidate?

SX25i Integrated Amplifier CapacitorsAt the end of the test our Perreaux SX25i should show it’s ability to feed floor-stand speakers. We didn’t want to raise the bar too high, so we decided to hook up the SX25i with a pair of ZU Audio Druid Mk4. Over 100dB degree of efficiency and 12 Ohm should be an easy game, we thought. Well, we did not have too much pleasure and we do not know why.

Maybe because the Druids are mids orientated speakers, which doesn’t go along with the previously mentioned weakness of our SX25i? Theoretically! Practically, I don't have anything to complain here. Well, bass really needs more punch here, but we could get over that. However the goodness of the ZU speakers is their fast tempo, their very high dynamic and their coherence but especially their ability to place the stage into the room wide open and volumetric. Well, that’s exactly what I am missing when driving them with our little SX25i. Some of the ZU speakers charm just goes missing. Mhh, could have worked out though.

Then why doing a further sound check with a pair of Thiel CS2.4? With respect to the equipment driving them there is often a chance that these speakers sound quite rheumy. Well, why then testing them? Maybe just to learn that a healthy common sense and acoustic performance doesn’t necessarily have to accompany with each other.

SX25i Integrated Amplifier Output NetworkQuite astonished, I was left sitting on my colleague’s sofa asking myself why the heck the mids don’t agitate me now, why (especially with this combination) the deep bass has a very healthy punch and why tunes dissolve in an very pleasant manner? This was definitely more than just “succès d’estime” what the little Perreaux SX25i delivered here. I pare myself a further enumeration on what else could be even better. Well, here you got it. The size of a car radio, not really designed to fill 30 square meter rooms and actually way too weak for speakers of such calibre. This little Kiwi shows itself very, very adult, mature and very hi-fi. Be it tonal, be it the tempo or be it the dynamic range or be it the great ability to dissolve within the room or it’s precise way of rendering the sound. Everything just mentioned I would have expected two classes lower.


Four things have to be clear, in case you decide to get this Perreaux SX25i integrated amplifier:

  • One source input is enough
  • You do not need a remote
  • The system this amp will be driving is not placed in a big gym
  • Max volume levels are not your ambition

If you can tick off these four points, then with this Perreaux SX25i you will get an amplifier that...

  • ...plays with lots of grip and very authentic upper-bass / lower-mids and which renders clearly but not aggressive at all in the high tunes. The little weaker deep bass playback falls within matter of taste. Only the higher-mids could be a little softer and less present here and then.
  • ...that has the ability to dissolve within the room very well, especially horizontally and with the ability of a very precise playback. The depth of the stage strongly depends on the combination amp / speaker. The middle of the stage tends to be the sweet point not it’s corners.
  • ...especially will be appreciated because of it’s vividness and it’s very dynamic behaviour. Impulse comes with a punch and spot on. The Perreaux does not even get thrown out of the curve by rhythmic pumping tunes. Instead of that the SX25i wants to give the listener a good dressing down!

The Perreaux SX25i delivers big time!

An acoustic dissection is one thing – a more realistic decision to buy or not to buy might be different though.

Mhh – how cute he is…

WOW – he knows how to play music…

Great – he doesn’t cost as much as the stuff you usually show up with…

I could imagine buying this thing very lively!

Feel free to view or download the SX25i Integrated Amplifier review (1.03MB) in .pdf format.

Original review written in German by Ralph Werner for online hi-fi magazine fairaudio.

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