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North Star Linestage Pre-Amp and Monoblock Mono Amplifier

Not Just Digital!

[Italian version]

Product: North Star Linestage Mono Amp, Pre-Amp and Monoblock Amplifier
Manufacturer: North Star Design - Italy
Approx. Price: 1500,00 Euro/$ (Linestage) 3000,00 Euro/$ (Pair of Monoblocks)
Reviewer: Stefano Monteferri
Reviewed on: October, 2003

[North Star Linestage + Monoblock Amplifier]
The excellent three-chassis North Star Amplifying System

North Star, with its digital equipment, and specially with the pair M192 CD-Transport + Model 192 DAC, has gained appreciation in the field from "fine hear" and budget conscious audiophiles.

Furthermore, TNT Audio had the opportunity to carefully test the aforesaid equipment with great and positive results. The tests have nothing but confirmed the quality of the products.

Given such sound background, I have welcomed with interest and curiosity Giuseppe Rampino's offer: "We got a couple of "almost ready" Monoblock Amplifiers, mono power amplifiers and we would love to hear TNT-Audio thoughts about them". After a while, the solid amplifiers were standing in my testing environment. A little bit later, the dedicated preamplifier, the Linestage Preamplifier, was lining with them. All in a rigorous silver finishing. (Available finishing: Silver, Silver/Black and Black).

Monoblock Amplifiers

Unpacking the boxes, I could not overlook the aesthetic value of the equipment that, despite the unusual look, shows a neat assembly. In particular, the thick aluminium front panel appears well finished and it's completed by a status LED (red light for stand-by, blue light for normal operation) and its related selection button.

What definitely will attract your attention is the Monoblock shape, clearly developed in depth. This seems to suggest the positioning of the unit close to the speakers, rather than inside a standard and common hi-fi rack.

On the rear panel, we find two input connectors (a balanced XLR and unbalanced RCA), an input selection switch, a pair of WBT connectors for speakers cables, a communication port (Trigger) to connect the Linestage, to control the amplifier stand-by function directly from the preamplifier and the main switch to turn the equipment completely off.

[Monoblock Amplifier]
Inside the Monoblock Amplifier

Looking inside the Monoblock, I have immediately appreciated the generous sizing of the power supply section, inclusive of a 500VA transformer (and armored toroidal that alone takes half of the available space) and a group of 8 capacitors with an overall filter capacity of 80.000 uF. The power transistors (4 pairs per each amplifier) are positioned beside the heat-sinks mounted on both sides of the equipment, spanning from the middle to the end of the chassis, almost reaching the rear panel.
In steady-state, the heat produced doesn't go unnoticed. A portion of the internal connections, and especially the ones dedicated to the signal, are manufactured using the prestigious Litz cabling from White Gold Electronics.

Here the Monoblock Amplifier factory technical specs:

The Linestage Preamplifier

It's a line-only preamplifier which, respecting the Northstar aesthetic standards, does show an unusual look: both CD Transport and DAC 192 are large and short, the Monoblock is long and narrow, and the Linestage of standard dimensions finally.

Center-positioned on the front panel, just above the status LED (that shows the Monoblock status if you use the Trigger connection), the volume knob. It is operated, similarly to the other functions, through the supplied remote control. On the right, there are two LEDs for selected source indication, a remote IR receive cell, two buttons for inputs selection and one for the stand-by function.

Inputs on the rear panel allow up to 6 sources (5 Un-balanced RCA inputs and 1 Balanced XLR input). The PRE OUT is both RCA (for simple passive biamping) and XLR (single). The rear panel is completed with a TAPE OUT, a Trigger OUT and the main power switch positioned just beside the IEC power socket.

[Linestage Preamplifier]
Inside the Linestage Preamplifier

Here the LineStage Preamplifier factory technical specs:


In the same period of time I was reviewing the North Star's components, I was also testing a pair of Sigma Acoustic speakers, the Overture model (Soon on TNT Audio!) and the excellent White Gold cables. Given the cooperation between the two vendors (NS and White Gold), I have also had available for testing, a set of CD Transport and 192 DAC (tried on TNT some time ago) provided with both the I2S standard cable and the new I2S Digital Link. The latter is custom made by White Gold for North Star only. North Star can in fact provide such cable on request to improve performances of the aforesaid set. The I2S Digital Link, result of a long and careful R&D and manual work, has been commissioned by North Star to White Gold and, later on selected among many Gianfranco Fanucchi's prototypes. We're hence talking about a dedicated CD + DAC cable that can only be purchased from NorthStar.

While I can only confirm what already expressed by Lucio Cadeddu in his review about the North Star CDT + DAC192 sound, I have also to underline that, using the I2S Digital Link cable, brings the set to a definitely much higher quality level.

The sound remains fluid and musical. The overall brightness increases providing a better sound image, with higher and more precise details. The improved microdynamics make the sound more vivid and impressive. The boost in the middle-high frequencies is clear and noticeable.

Therefore, the use of the digital cable I2S White Gold, provided as an upgrade by North Star, substantially improves an already valid system. One suggestion to the owners of the CDT and DAC 192 set: if you really want to explore the full sonic potential of your digital source, put aside any possible skepticism and test the cable. Whether possible, in the peace and quiet of your home.

Ain't Just Digital

Let's start then with the actual subject of this review. During the test, the synergy between the pre and the mono amplifiers was so evident that I decided to write the review considering the combo as a whole. The North Star system, once reached the steady-state, immediately captures the listener's attention for the way it manages to balance the emission of raw power with delicate sound. It appears immediately evident that the power amplifiers can drive, without any hesitancy, "tough" load speakers. This confirms North Star's statement about the Monoblocks stability and potential in managing tough loads. The bass is deep and energetic, consistent on long notes, strong when needed and lacking of any uncertainty.

Mid-low frequencies are lovely, well articulate and not intrusive at all. Such characteristic reminds me the same North Star CDT + DAC 192 tone settings. This feeling was later on confirmed by a fluid and delicate mid range associated with a charming well-refined mid-high range.

Very-high frequencies are neat and extremely detailed confirming the overall feeling of great definition that keeps the listener constantly concentrated and fascinated by the sound.

[Monoblock Amplifier's Detail]
Monoblock Amplifier's Detail

There's no sign of sound inconsistency then but a fluid and homogenous tonal response associated with a high level of musical transparency. With such interpreting ability, the amplifier is able to preserve the harmonic tones of all different instruments presenting them with a deep realist touch. In short, even if this is the first North Star amplifying system attempt, the sound quality revealed by the three-chassis system, cannot be an unexpected event, but rather the result of a coherent and determinate audio philosophy. Great! It means that at North Star they have a very clear understanding of which results they want to reach and how to achieve them.

The dynamic expressed is, with no doubt, satisfying. At low volume levels, the system releases a fluid and relaxing sound, similar to a powerful yet silent car engine that hums peacefully, letting you to enjoy the (musical) landscape which develops around you. The sound landscape is offered with kind and gentle manners but with extreme heed, in a way that every single microdynamic information reaches your ears intact. By just turning up the volume the music changes (so to say...). The Monoblock Amplifiers start to express their "torque and power" talent, pushing really hard without any hint of giving in. Full orchestras, choirs, dynamic modulations of more powerful instruments are released without any feeling of compression, without any evil distortion that could irritate the listener.

The North Star system takes you then into a deep holographic musical environment in which the the listener can feel the physical impact of the music. This is a very satisfying result. I smile recalling when, due to some mistakes I made connecting the pre and the amps, I doubted about the quality of this Made In Italy system (pay attention at how you connect the Linestage to the Monoblocks!).
Could it be any better? Absolutely! I have listened to other amplification systems that are excellent in situations in which the North Start performs just "good". However, to be honest, I do not recall too many competitors that, at the same price, offer a versatile and well finished premplifier and a pair of so powerful, well-made mono-amplifiers able to drive any load, delivering a valid and complete sound.


On the rear panel, the WBT clamps, CE compliant, are a real disaster when it comes to connect speakers cables spade-connectors fitted. Yes, it's true that this will prevent any accidental short-circuit but...what a hassle!

The narrow shape of the amplifier, developed in depth, can be considered critical if you intend to install it in a standard hi-fi rack (even though, given the feet are 40cm from each other, its stability on the shelf is not compromised). On the other hand, if the Monoblock is installed close to the speakers, the reduced front encumbrance could become an advantage.

At the end, a little complaint that, to be honest, should be made to many products on the market. It seems that the "standby-mania" is spreading all over the places. Well, I do not find (almost) anything wrong in this respect. However, I'm used to turn off all equipment when I do not use 'em and frankly, the idea of gropingly look for the main power switch on the back panel of the unit, it doesn't drag me along.
Oh, how much I'd like to use again fat and robust main power switches located on the front panel of amplifiers or on any other equipment!


What in the beginning was supposed to be just a the test of the Monoblock Amplifier, at the end of the day(s), it turned out to be a much wider review. Nothing to be sorry of. Rather the opposite. When I deal with interesting equipment I always manage to enjoy spending time on what, after all, is one of my favorite hobbies.

The ampliers appear to be able to drive everything, and the power (released power) is surely not missing. If you decide to buy this pair of monoamplifiers, it is unlikely you would then feel the need of anything different, unless you're looking for top notch stuff and money ain't an issue. Or you are sensitive to the brand appeal. Please don't misunderstand me, I do not see anything wrong in that.
What is important is to be conscious that usually, together with tubes, transistors, fancy stuff and sound quality, you pay for the brand as well.

I'm aware that, quite often, the audiophile loves and enjoys setting up his hi-fi system diversifying, as much as possible, the different system's components. For instance, some people state that a tubes pre-amplifier should be paired with solid state power amplifier. And they love such an intriguing solution.

I have no doubt that, in many cases, interesting results can be obtained in this way, but please consider that the whole system Linestage Preamplifier + Monoblock Amplifier has been designed specifically by North Star to achieve optimal performances. I strongly advise you to consider this aspect in case of listening sessions or tests.

Our compliments go to North Star for this, definitely well designed, first "stroll" on the Multi-Chassis subject. Special thanks to Eng. Giuseppe Rampino for his time and provided support.

© Copyright 2003 Stefano Monteferri - www.tnt-audio.com

Translation: Gabriele Galli

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