Audia Flight FLS10 integrated amplifier

The dogma of separates has long reigned supreme among audiophiles: If you're serious about sound quality, you're supposed to need a dedicated preamp and power amp. The logic goes that separates reduce interference and offer maximum control over your sound. But there's an argument to be made that integrated amplifiers are more practical ... and potentially better-sounding.

The beauty of an integrated amp lies in its synergy. Audio engineers know exactly how the pre and power sections will interact; the two are literally designed to work together. On paper at least, that means optimized impedance matching, and signal integrity that can rival and perhaps surpass separates. How do you know whether a standalone preamp is a great match for a power amp? For most of us, it's through trial and error. It isn't unusual for restless stereo aficionados to own multiple combos over the years, in search of the ideal one. That gets costly.

Then there's the fact that an integrated amp helps declutter a room, appealing to minimalists and people whose living spaces are less than cavernous. Another plus: no need to shell out for audiophile-grade interconnects.

The why and how
The Audia Flight FLS10, an Italian integrated, came into my life because I'd been scratching my head over a pair of top-of-the-line Diptyque panel speakers that I'm planning to review for this magazine. Once I had them in my home and properly set up, the Diptyques' midrange and treble was as lush and engaging as I remembered from the Tampa and Chicago audio shows where I'd heard them. Bass, however, was another matter. The lower octaves seemed on the lackluster side. I knew that the speakers weren't at fault, because on those previous occasions they'd reproduced bass frequencies superbly. The Diptyques seemed to cry out for something grippier than the tubed monoblocks with which I'd paired them.

I considered using a tube amp for the mids and highs and a solid state one for the bass, but each Diptyque Reference has only a single set of binding posts. The next best plan: a solid state amplifier fed by a tube preamp—to wit, my recapped Krell FPB 200c reference power amp paired with the wonderful Margules SF-220 tube preamplifier that's shone in multiple pairings in my room. Just in time, however, I remembered that Krell FPB amplifiers have a peculiar limitation: The manual cautions that before you can safely use an FPB with a valve preamp, "coupling capacitors must be inserted into the signal path" by authorized service personnel. Ugh.

I didn't have another power amp/tube preamp combo on hand—at least not of the quality that would do the Diptyques justice. As I started considering solid state solutions, I received sage advice from Michael Hoatson, a prominent Diptyque dealer in Maryland (footnote 1) and an indefatigable panel-speaker evangelist. He was blunt about it: "Audia Flight is the best you will ever hear a panel."

As it happens, Diptyque's US distributor, Fidelity Imports' Steve Jain, also carries Audia Flight's products. In fact, the Italian amps had been used to drive the Diptyques at the audio expos I'd visited. That settled it. A loan was arranged, and some weeks later, a wooden crate showed up at my door containing the Audia Flight FLS10 fully balanced integrated amplifier.

The PDF manual I'd already perused advised to simply unscrew the crate's lid, but there were no screws on the top, only nails. That necessitated using a hammer and a small crowbar, after which the rug in my room was full of splinters and woodchips, and the crate looked like it had been gnawed on by bears. Scusami tanto!

My friend Matt and I took the lid off the crate and manhandled the 79lb amplifier onto the top shelf of my audio rack, 3' off the floor. I made the necessary connections (footnote 2) and hit play. Presto: taut, deep bass, complete with slam and authority. From a pair of panel speakers, no less!

Over the next couple of months, the dual-mono FLS10 demonstrated its mettle and versatility by also coaxing terrific performances from my Focal Scala Utopia EVO reference speakers. Then the same amp made a pair of Estelon X Diamond MkIIs sing in full-throated but controlled fashion (see my appraisal of the Estelon in the January issue). I hadn't intended to review the Audia Flight, but it was clearly a worthy subject despite not being a recent release (the amp was introduced in 2017). Based on my enthusiasm for the Italian charmer, Editor Jim Austin agreed to a review, so here we are.

Getting acquainted
Funny thing: I hadn't especially liked the FLS10 when judging it purely on design and ergonomics. The large stepped volume knob on the right of the half-inch–thick fascia is recessed, sticking out only 0.18"—less than the length of a match head. It's not very easy to grab and spin.

Compounding my reservations was the FLS10's remote control. It has eight identical half-sphere buttons, each the size of a small ball bearing. The simple uniformity looks attractive, but it doesn't make the device a cinch to operate by touch. Over time, I made peace with the remote and learned to appreciate its pleasant heft (but not the fact that you have to remove five noncaptive screws to replace the CR2032 coin-cell battery).

A final niggle concerns the two-line blue OLED display on the FLS10, mounted inside a swoopy 11"-wide strip that looks a bit like the visor of a space trooper. Each line can display roughly 15 dot-matrix–like characters, providing handy feedback such as volume level, input selection, and other basics. But the swoop gives the top of the casework a slight overhang, a kind of brow, so that when you're viewing the display from a standing position, the top line is obscured. In fact, so is the bottom one if you're closer than a couple of feet. This means that when you press any of the controls on the front panel, the screen is practically invisible ... unless you've placed the FLS10 at eye level. If not, you'll have to bend down or crouch to see the readout.

But honestly, after a couple of months with the amp, I had come to regard all those things as charming quirks rather than deal-breaking shortcomings (footnote 3).

From left to right, the six small sunken controls on the fascia are the amp's on/standby switch (the actual off switch is on the back); the input selector; a menu button that lets you change various parameters via the volume knob; a mute button; a phase toggle; and a "disable speakers" switch that you press when you jack a pair of headphones into the ¼" input on the right. Except for that "SPK" button, all these functions are also available on the remote control. An LED near the bottom center lets you know if the amp is in standby mode (amber) or fully on (blue).

Around back we find eight gold-plated speaker terminals instead of the usual four, to facilitate biwiring. Then there are three sets of RCA inputs, two pairs of balanced inputs, RCA and XLR outs, a REC output, a power switch, and the usual receptacle for a three-prong IEC power cable. That's on the standard-issue FLS10. The removable covers on the back are for optional expansion boards, such as a user-installable MM/MC phono stage ($1499). The FLS10 I received also arrived with a DAC module ($2499), which features five galvanically isolated digital inputs: asynchronous USB, two TosLink optical, an S/PDIF coaxial, and an AES3. I made extensive use of the latter two, by feeding them the signal from an Aurender A20 and a Grimm Audio MU1, respectively. Audia Flight uses an ESS ES9028PRO DAC chip (the same one we see in the formidable Benchmark DAC3). The DAC's dynamic range is given as 133dB, THD+noise as <0.01%, while the music streams up to 32-bit/384kHz/DSD512.

Audia Flight says on its website that "the amplifier's main power supply is made by 16 18,000µF 50V low impedance capacitors and is then composed of two super high current power supplies per channel, as well as four stabilized independent stages per each channel: two for the input stages and two for the Audia Flight current feedback stage."

A 15VA toroidal transformer is dedicated to the logic control and protection circuit, keeping it isolated from the audio section. Inside the chunky aluminum chassis we also find custom-printed circuit boards made with extra–high-grade copper, and "a 2000VA toroidal audio transformer enclosed within two ferromagnetic shields and encapsulated by epoxy resin powering the output stage." Because the Audia Flight team believes that "fuses are like resistors and can negatively impact the sound," the company instead uses "a current sensor read by a microprocessor." The amplifier's output stage performs in class-A for the vital first 8W ... and runs pretty hot as a consequence. My digital infrared thermometer measured 103°F on the middle of the top plate and 115°F at the heatsinks on the sides.


Footnote 1: See listenroom.com.

Footnote 2: "The use of interconnect and speaker cables of the highest quality is strongly recommended," says the FLS10 manual. I mainly used cabling from AudioQuest's upper tiers: Thunderbird Zero cables for the speaker connections, a WEL Signature AES3 cable for the Grimm MU1 streamer, and AQ's Coffee coax and Vodka TosLink cables for other digital components.

Footnote 3: It reminded me of my 2008 Saab convertible, which I drive whenever the Maine weather allows. It has a button marked AC OFF; embedded in that button is an LED. When the LED is on, the air conditioning compressor is off. If you press the button, the light goes off—and that means the compressor is now on. How convoluted and unintuitive is that? But after a few months of ownership, that crackbrained control had become endearing to me. It somehow made me like the car more. And so it was with the idiosyncratic aspects of the FLS10.

COMPANY INFO
Audia Flight
Via Alfio Flores 7
00053 Civitavecchia (RM)
Italy
info@fidelityimports.com
(609) 369-9240
ARTICLE CONTENTS

COMMENTS
Glotz's picture

I want this for every reason elucidated in the review, but the 63hz hum gives me pause and the fascia/design for the casework isn't my style. But whatever, everything else about it is exemplary!

The price point is lofty, but one I think meets its performance envelope communicated from the review. For it to challenge a long held reference via the Krell's proves it's pedigree for RVB (and in kind is an insightful observation for the reader).

I will have to hear this again at this year's show!

John Atkinson's picture
Glotz wrote:
I want this for every reason elucidated in the review, but the 63hz hum gives me pause . . .

It's not hum at 63Hz but hum at –63dBV, ie, 0.07% ref. 1V into 8 ohms.

John Atkinson
Technical Editor, Stereophile

Glotz's picture

I was thinking 63dB down but was distracted at work. ;)

The 3rd photo made me pause earlier as there is another smaller logic transformer over the really huge transformer underneath. That thing is monstrous! As mentioned, but what can you do with a large integrated?

It was awesome when I heard it, but a few minutes isn't really enough time. I'll hold off on strong opinions. I'm sure I'll be smiling at AXPONA...

Glotz's picture

It does remind of Calatrava's Milwaukee Art Museum, but not enough! Lol. I would have loved even more sculpting! I think for $15k a little more artistic expression is important.

georgehifi's picture

Paul:"Moreover, there's sufficient capacity in that huge PSU to sustain 265W, 500W, 885W, and a full 1385W (37.2A) into 8, 4, 2, and 1 ohm, respectively, under dynamic conditions"

(37.2A)? Peak or continuous.
The use of the word "sustain" to me says (continuous) wattage, but after that you say it's just "under dynamic conditions"(peak)???

Cheers George

kai's picture

You wouldn’t want 37 A continuously run through your speakers.
It would make them shine bright - literally.

georgehifi's picture

"You wouldn’t want 37A continuously run through your speakers.It would make them shine bright - literally."

If it's 37a peak, old NAD 3020 will do something like that

All about running out of breath into very low impedance load, + it's a bridged amp which makes it even more less tolerant of low or low epdr loads, like Class-D's can also.
Amps like Gryphon and D'Agostino won't do that as they can go to 100+ amps.

Cheers George

kai's picture

At “a full 1385W (37.2A) into … 1 ohm” there’s not much to worry about this thing running out of steam.
I have yet to see a speaker that can handle this without going into overload one way or the other.

georgehifi's picture

When Gryphon's Krell's and Dagostino's etc etc can do 100A with less 8ohm wattage, we all know know which will be the one running out of breath first.
As for the 1385w, I can get a 6000w Crown amp for just $1000!!! but it won't drive high end speakers with nasty loads like the ones above can.
Cheers George

kai's picture

There might be a little misconception:

The 37 A, or 100 A or whatever Ampere are only drawn if an amp is driving a very complex load that goes down to 1 Ohm, at full power.

37 A into 1 Ohm equals 1,369 W.
100 A into 1 Ohm equals 10,000 W.

In reality both of these powers are way high enough to melt every existing speaker’s voice coil.
But at home use the quality of the first one Watt is what counts, most speakers need less than this for normal listening.

Like having a car that can go 250 mph, then asking for one that can go 500.
In reality driving at a max. of 55 mph.

High power semiconductors BTW are slower, it’s easier to build a quality smaller amp.

georgehifi's picture

Ah that's quite a big no!
Into speakers like the the Wilson Alexia a 150w 100A Gryphon/Krell/D'Agostino etc will sound more powerful with better drive/control and dynamics into that load than a Crown that has 6000w!!! and only <30a peak.

Cheers George

Cheers George

kai's picture

The 6,000 W Crown is made to power PA systems at live music events in big halls.
It‘s intended to be used in it‘s upper power range.

Typically those amps are not suited for home use, where their fan‘s noise might blow louder than the music sounds people want to listen to.

Reducing an amp to it‘s current capabilities falls very short anyway.
Tube amps e.g. don‘t have any current capability above their nominal power.
Does this make them sound weak?

The strongest Class D Crown amp I found on a quick glance was the Crown Xti 6002.
6,000 W into 4 Ohm, mono bridged.
At a price point around 2K take 2 and you got enough power to blow the roof from your house.
Current capability BTW at least 39 A RMS, for the nominal continuous power.

Is it this one you heard?

kai's picture

If you look at the densely stuffed internals, interconnected with a dish of spaghetti (wires), you know where the advantage of a separated pre-/power-amp design lies:
This thing is close to unrepairable once any of it‘s cramped parts breaks.

Ortofan's picture

... either the E-4000 or E-5000 (along with the optional analog disc and DAC boards) from Accuphase.

https://www.accuphase.com/model/e-4000.html

https://www.accuphase.com/model/e-5000.html

If the reviewer is going to be making a comparison to a Krell class-A amp, then he should be reviewing the Pass Labs INT-250 (along with the XP-17 phono stage and one's choice of DAC).

https://www.passlabs.com/products/int-250/

https://www.theabsolutesound.com/articles/pass-labs-int-250-integrated-amplifier/

https://www.passlabs.com/products/xp-17/

https://www.theabsolutesound.com/articles/pass-laboratories-xp-17-phonostage/

unitygain's picture

I had similar concerns during the time I owned mine, but it’s a great amp. Sonically, it was exceptionally vivid and controlled while I had it – with remarkable leading edge precision, a humongous soundstage, and unflappable control (at the aruguable expense of slam) when delineating even the lowest bass registers.

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