Atoll IN400 Integrated Amp, $7000 (180×2)

{5.11h, 17.32w, 14.17d, 43 lbs}

Atoll IN400

Atoll’s IN400 is a true contender for state of the art integrated amp!

It is built in Atoll’s factory in France with a three year warranty. It isn’t designed in France and built in China. Nor is it a pile of Chinese parts assembled in France to try to fake you out.

Atoll is an honest to gosh, family owned company in a day and age where most of its competitors are subsections of hedge funds. Atoll delivers a level of TLC that the other guys simply can’t.

The heart of IN400 is its power supply. It starts with a ginormous 1050VA transformer that Atoll has designed and has built for them in Spain. It is an internal dual mono structure. It has separate windings for each channel. It uses a second 1.6VA transformer for control logic.

The filter caps are also designed by Atoll and are custom built for them in Japan. IN400 uses almost 100,000uF in power supply caps to help deliver a rich and weighty musical character.

IN400 is mechanically stout. Its face plate is just under one half inch of micro-blasted and anodized aluminum, with high precision engraving. The chassis is made of steel. Heat sinks are machined aluminum construction.

IN400 runs 8, MATCHED MOSFET output transistors per channel. This is a vital part of Atoll’s TLC. Imagine you have a tuning fork tuned to middle C. Then you add another and play them simultaneously. If they’re not precisely the same- you incur distortion artifacts.

Relay this analogy to an amplifier’s performance. If you run, in this case, 16 output transistors, all buzzing away at their own whim, you’re guaranteed to get grainy results. Atoll takes the time to hand match its transistors so you’ll achieve a more ebullient character in your music. This explains why, historically, higher powered amps sound more grungy than their lower powered siblings. The more power and transistors you run, the more harsh the amp will sound. Twas ever thus.

Atoll takes assiduous effort to be sure its more powerful amps are just as mellifluous as the rest of the family. You pay no penalty for greater horse power with Atoll. With virtually everyone else, the bigger they are, the nastier they sound.

With this long-winded preface behind us… it is in a singer’s voice that IN400 first grabs me. Toss on a buoyant singer with acoustic guitar (Joan Armatrading “Love & Affection”) and be prepared to hear resolution and ambiance galore. Joan’s breathy presentation is a thrill to hear! Plenty of amps will play this “cleanly.” But to imbue the soundstage in front of you with so much space and air takes on ethereal beauty. It made me think of fireplace bellows of massive capacity vs flimsy ones. Run through a variety of great speakers (Bryston, Magnepan, Atohm) I know very well, they all sounded more capacious with IN400 than anything equal or less money.

IN400 delivers this lovely level of open/airy sound- without adding a hint of BRIGHTNESS up top. This weighs heavily in my recommendation of Atoll. We get the spacious soundstage without a sharp high end, or a darker slant- which typically occurs with tubes.

It would be absolutely fair to say IN400 will please any tube lover with its character! You’ll derive this flavor without the heat, hassle and noise endemic to tubes.

IN400 has a muscular low end- much weightier and more convincing than any D designs. Further, its balance is more hefty and impactful than amps that skew overly taut.

While no amp is perfect, we’re always looking for the best performance we can achieve at a given price point. What makes IN400 my fave is that it gets the MOST IMPORTANT vocal region (whether humans, pianos, acoustic instruments) done better than any integrated I’ve heard.

IN400 does this without a crispy top end or thin bass response. I don’t want tubes with their heat, noise, sluggish bass and poor reliability. IN400 is a ground breaking integrated at an attainable price for people (like us!) who value singers, pianos and the sound of exquisitely crafted acoustic instruments.