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This review first appeared in the February 2009 issue of hi-end hifi magazine High Fidelity of Poland. You can also read this review of the Belles IA-01 in its original Polish version. We publish its English translation in a mutual syndication arrangement with publisher Wojciech Pacula. As is customary for our own reviews, the writer's signature at review's end shows an e-mail address should you have questions or wish to send feedback. All images contained in this review are the property of High Fidelity. - Ed.

Reviewer: Wojciech Pacula
Review system: Go here
Review component retail: 22.000zl
The Belles model IA-01 is part of their Statement series. I never heard of the company or series though perhaps I saw some advertisement or read some text but don't remember when and if for sure. Belles is a small enterprise and the brand is owned by David Belles of Power Modules Inc. The company website states that the company has manufactured amplifiers for already 30 years and that most of them work in class A. During the review of the IA-01 I learned how much it costs (after the listening session incidentally), how it is named and that the output stage works in class AB.

There was no manual in the box and no information on the company page about one. A tad more information is supplied by its US distributor who states that this new integrated amp is based on the MB200 power amplifier and LA-01 preamplifier, that it outputs 180W (at 8Ω), is capable of 40A peak current and has a very wide frequency response from 0.2Hz to 125kHz (no -3dB points given). A look inside confirms very short signal paths (except for long flying leads conducting the signal to the potentiometer) and that the design is based on discrete solid state components with Mosfets in the power buffer.

Looking at its size and power, it's easy to guess that this device works in class AB. It is very well crafted, looks nice and is built in the USA from beginning to end. The unit is rather sparse on bells and whistles with four line inputs and one preamplifier output but sufficient for purist systems. All functions (volume, input switching and mute) are accessible from a small remote. Already at first glance, this really is a very nice amplifier. As you will see it, had tough competition from renowned companies like Pass, Accuphase and Luxman, which, while more expensive, are direct competitors.


Discs used for testing: Dire Straits, On Every Street, Vertigo/Universal Music Japan, UICY-93734, SHM-CD | Solveiga Slettahjell, Silver, ACT 9715-2, CD | Maria Peszek, Maria Awaria, Kayax Music, 24358521, CD | Porcupine Tree, On the Sunday of Life, WHD Entertainment, Inc., IECP-10137, CD | Genesis, Calling All Stations, Virgin Charisma/EMI Music Japan, TOGP-15019, SACD/CD+DVD-A | Harbie Mann & The Bill Evans Trio, Nirvana, Atlantic/Rhino, 90141, CD; Atlantic/Warner Music Japan, WPCR-13181, SHM-CD | Gerry Mulligan & Thelenious Monk, Mulligan Meets Monk, Riverside/JVC Music 0032-2, XRCD | Woong San, Feel Like Making Love, Pony Canyon Corea Inc. PCCY-50014, HQCD.


The integrated IA-01 Belles amplifier is a very nice sounding device crafted with love which has the luck/misfortune (cross out the unnecessary) to fall into a broad price category (about 15000 – 25000zl) that is occupied by many other, far better known and represented brands. Using my memory and archives, I would like to single out a few splendid amplifiers against which the IA-01 will have to compete:

I would like to point your attention at the Polish JAG in this group being four times cheaper - and the German Trigon at half the price. The first is based on 300B tubes and works in SET configuration. It is not as good as the Belles in absolute terms but presents midrange resolution and space in a way none of the others can match. It is similar for the Trigon, a fantastic but inexpensive amplifier whose coherence, timbre etc. are so good that even with a €20000 budget, we surely have to consider it on our quest and spend the money saved on a top-grade or almost power cable (no I'm not joking).


First things first. The Belles has great smoothness devoid of harshness and very good tonal balance (I am thinking about the whole picture). The upper treble and lower bass are not especially strong and resolved and in both cases the reference system (Leben RS-28CX + Luxman M-800A) showed much more information. On the other end of the price scale, only the C.E.C. AMP6300 (which could be added to the above list) played the treble in a comparable but not identical way. Despite appearances of what I already wrote, the Belles has nothing in common with restricted frequency response or dullness. The Trigon and JAG are much warmer. Ditto for the Accuphase units. The transparency of the IA-01 is very good and its vividness splendid. The American amplifier also shows off the vocals very well. The midrange walks a very thin line without hardening and thickening the contours but still very nice three-dimensionality with splendid accompanying decays. I noticed that already on the first disc On Every Street by Dire Straits. The comforting feeling of a job well done remained with me until the end of the session through discs like Maria Peszek's Maria Awaria or Solveig Slettahjell's Silver. The sound combines clarity and warmth yet this is no warm amplifier in the sense of describing the Accuphase E-450, Pass INT-150, Trigon Energy or JAG 300B. The 'warmth' of the IA-01 is only a manifestation of its lack of harshness, not outright embellished part of the frequency spectrum. A part of the midrange somewhere below 1kHz is slightly stronger however to make the attack of 't' and 'k' sounds stronger than the higher placed 's', 'c' and similar. This gives no harshness -- we are lower -- but it did dynamize the sound and you need to be careful with your loudspeaker choices. It is not about finding bright or vivid loudspeakers but those that are very even. I would not fight for opening up the sound as the Belles is not closed off. It simply plays treble in a delicate and soft way without disconnecting it from the rest of the bands nor damping it.