Luxman L-550AXII Integrated Amplifier Review

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Luxman L-550AXII integrated amplifier

By Steve Folberg

Memory Lane

Long before the Luxman L-550AXII ever graced my door, there was a stereo system. I bought my first real system just out of graduate school in 1985: a Systemdek turntable (with a glass platter and the worst suspension system ever slapped into a turntable), a used Linn Basik tonearm with some long forgotten Audioquest cartridge, a PS Audio Elite Plus integrated amp, and a pair of the original Vandersteen 2C loudspeakers, bi-wired with some fat, ugly, Monster Cable speaker wire scattered all over the floor. I also had – I kid you not – a Carver C9 Sonic Hologram Generator, which could simulate the experience of Fritz Reiner conducting the Chicago Symphony while you sat in the middle of the trombone section. Bizarre, but fun.

Anyway, back then, a female coworker stopped by the house, saw my living room and sneered, “You’d better enjoy this stereo while you’re single because no woman is ever going to put up with this mess.” But I didn’t care. Ugly as it was, I loved the music that system made and would spend at least two hours a night spinning LPs after work. I was happy and had no thought of upgrading (except when my frustration with the Systemdek ‘table skipping every time I took a step motivated an upgrade to a SOTA Sapphire, which I still use today).

Marriage, a cross-country move, and, especially, new parenthood left the rig mostly boxed up and unused, until an early 2000’s home remodel created a bit of space for the stereo once again.

The bad news: the room was small, the Vandersteen’s wouldn’t fit, and the amp had developed some problems (later fixed) in storage. The good news: I finally had an excuse to get back in the equipment game.

This led to a jaw-dropping discovery: Since I had last paid attention to the high-end audio scene in 1989, brick-and-mortar stereo stores seemed to have all but vanished. But this new invention called the Internet now made it easy to upgrade, by horse-trading gear on websites like Audiogon, eBay and (much later) US Audio Mart.

Within a few days, I was spending far too much time perusing the ads on said websites, with the goal of replacing those Vandy’s with something that didn’t need to be 5 feet out into the guest bedroom to reach their full potential.

From time to time, large boxes would go out the front door on their way to UPS, and other large boxes would come through the front door. My wife and daughter would tease me as I wrangled one of these massive cartons into the house: “New speakers again, Dad?” This frequent speaker swapping continued for the better part of ten years, as products by Merlin, LSA, Totem, Silverline, Reference 3A, Tekton, PSB and a few others I’ve probably forgotten, passed through that guest bedroom.

Seeking Simplicity

Flash forward to about six months ago. While writing a review of the Spatial M3 Turbo S speakers for my little audio blog, I was shocked to learn that my M3’s sounded much better powered by a borrowed, solid-state Krell amplifier than by my beloved Audio Note Kits “Kit 1,” an 8 W, single-ended triode (SET) 300B tube amp. It turns out that the Spatials were sensitive enough to be played loudly with 8 W of SET power, but the M3’s mountainous impedance curve would be too hard a load for any single-ended triode amp.

Since then, I’ve been searching for a solid-state, integrated amp that would allow my M3’s to really sing. I was therefore especially delighted to take delivery of my review sample of the Luxman L-550AXII integrated amp. As they say here in Texas, “I have a dog in this hunt.”

Why choose an integrated amp and not separates? Chalk it up to past frustration: At one point in the evolution of my system, I owned two Manley Mahi mono-blocks and a Manley Shrimp preamp, along with a DAC, turntable and CD transport. I tired of the fact that I had to flip 5 power switches and press three DAC buttons just to play a CD. I also tired of all the times I hit Play on the CD remote and heard nothing because I’d forgotten to select the right input on the DAC. It was time for simplicity.

Enter: Luxman L-550AXII

It was a pleasure to see how well the Luxman amp was packed, double boxed in the heaviest two-ply corrugated cardboard I’ve ever seen. Not surprisingly, the build quality of the amp itself is fantastic, as it should be at this price point – the MSRP is $5500 US. While the L-550AXII isn’t “audio jewelry” compared to, say, the “steampunk” look of some of Dan D’agostino’s latest amp designs, the fit and finish are exceptionally fine, from the half-inch thick faceplate, to the buttery smooth feel of the front panel rotary switches; from the satisfying click-thump of the detents on the input selector knob to the tactile refinement of the volume control. The aluminum, full function remote control (which will also control a Luxman CD player) is a pleasure to hold and use.

The Luxman L-550AXII is an analog-centric device, bucking the “Swiss army knife” trend of bundling DAC’s and all manner of digital inputs into a single chassis. Although I see the appeal of all-in-one preamp/power-amp/DAC solutions, I’d guess Luxman figures that at this price level, you’re going to want to pick your own DAC, anyway, so why stuff one into the box?

Luxman L-550AXII

Lookee-Loo, Lux

That said, the Luxman L-550AXII is no stripped-down, minimalist product, especially when it comes to connectivity. On the rear of the unit, we’re greeted by 4 pairs of line level inputs (RCA), one pair of balanced inputs (XLR) – which I used to connect my Musical Fidelity M1 DAC – and connections to a built-in phono stage with both moving coil and moving magnet settings, as well as in- and outputs for recording, and another pair for using a the 550 as a standalone power amp or preamp. All these physical connectors ship with protective plastic plugs to shield the inputs when not in use.

Outputs include binding posts for two pairs of speakers (labeled “A” and “B”). Just a note of caution that the actual metal posts of these high-quality, clear-plastic-shielded shielded binding posts were too thick to accommodate the spade lugs of my Supra Classic 6.0 speaker cable, and the plastic shielding didn’t allow me to poke one side of the spade through the bare wire hole in the post to get a connection, either. I tried attaching banana plugs to the cables, which fit just fine but didn’t sound as good as unterminated bare wire, so that’s what I used for this review.

Luxman told me that they source their binding posts from a couple of manufacturers and pay greatest attention to how they sound. I’m not a huge fan of those on the L-550AXIIdue to the fit issues I encountered, but as you’ll see shortly, they sounded great.

The front of the Luxman L-550AXII is festooned (love that word) with all manner of dials and buttons, all sporting the same, precision-machined aluminum goodness. These control tape monitor on and off, phono cartridge loading, recording out on or off, speaker selection, treble and bass tone controls and balance control. There is also a button which can engage or disengage Line Straight mode, which bypasses the tone controls, balance control, monaural mode and subsonic filter (to filter out rumble from warped LPs). According to the Owner’s Manual, Line Straight mode “enhances the purity of the sound quality” by sidestepping all these circuits. I did nearly all of my listening in Line Straight mode.

There is also a button labeled ‘Separate’, which allows you to bypass the preamp section (for use with a source with its own volume control). Finally, the Luxman L-550AXII sports a headphone jack. Note that plugging a pair of cans into the jack does not automatically mute the loudspeakers; you have to do that manually with the Speaker A/B/OFF dial.

Looking at the entire line of Luxman amps, a consistent design note is the presence of two large VU meters on the front panel. They have a cool, retro look, but they don’t provide much useful information and, as large as they are, the needles are so thin that I couldn’t read them from the listening position, anyway. If you find the meters distracting, a button on the remote control allows you to switch off the backlighting and, in a nice aesthetic touch, the backlights fadeout (and back on).

Classy Class

The Luxman L-550AXII is the entry-level model in their lineup of Class A integrated amps. In a Class A amplifier, the output devices (usually tubes or transistors) are running at full power, switched on all the time. In audio geek terms, Luxman “biases” the amplifier so that it operates in pure Class A mode. A Class A amplifier will be drawing maximum power all the time, even if there is no musical signal passing through the amp.

Where does that wattage go when there is no incoming signal? It is converted into heat, which is why Class A amps are sometimes referred to as “space heaters.” It’s also why you’re not going to find an “EPA Energy Star” sticker on a Class A amp, because they start sucking their maximum power out of your wall socket as soon as you switch them on. The Luxman under consideration draws 170 W at idle (switched on but no musical signal passing through).

Why, then, does Class A amplification have such audiophile cachet and command top dollar? Because well executed Class A designs don’t have to apply various engineering Band-Aids to compensate for the distortions inherent in other topologies that turn the output devices on and off (like Class A/B and Class D). This helps Class A designs produce a particularly sweet, musical sound.

Speaking of controlling distortion, the L-550AXII sports the latest iteration of Luxman’s proprietary ODNF, or Only Distortion Negative Feedback. Although Luxman holds the worldwide patent for global negative feedback as a distortion reduction technique, they don’t use it, substituting ONDF to apply negative feedback only where absolutely necessary to neutralize distortion. Also, Luxman’s volume control (which they call LECUA 1000, for “Luxman Electric Controlled Ultimate Attenuator”) is a proprietary mix of technologies said to reduce distortion in the volume control stage.

Use Me

You power on the unit by pressing the “Operation” button on the amp or remote. For fifteen seconds, a blue LED under the Input Select knob flashes (it also flashes when you adjust the volume with the remote) and then, with the click of a relay, you’re in business. Music sounds good at this point but gets better after 15 minutes or so of warm up.

Speaking of warmth, the Luxman L-550 AXII doesn’t run all that hot for a Class A amp, at least not as hot as some Class A tube amps that provide a tube cage to prevent serious burns. The most you’ll notice in typical operation is a steady current of warm air rising from the vents on top of the chassis. I never perceived the room getting at all warm (except for the couple of times I accidentally left the amp running overnight with the door closed).

Luxman L-550AXII rear

Listening to a Luxman

To my complete surprise, after breaking in the amplifier for about 120 hours and sitting down at last for some serious listening, the first word that came to mind was “powerful.” As in “mighty,” “thunderous” and “big.” With only 40 W into 4 ohms and 20 W into 8 ohms, this is not what I was expecting to hear.

Perhaps Luxman’s power output ratings are very conservative, or perhaps this muscularity is due to the “full throttle” nature of Class A amps paired with the 95 dB efficiency of my Spatial M3’s. Whatever the reason, the Luxman L-550 grabbed hold of those speakers and drove them with confidence and control.

This was particularly striking in the bass region. I’m talking about room-energizing, deep, tuneful bass response. This reminded me of something Clayton Shaw of Spatial said to me when I told him I’d be reviewing a Luxman Class A amp: “Oh, that’ll be plenty of power. Class A amps are a whole different deal.”

Basso Profundo

Jazz KaleidoscopeThe deep, nearly wall-shaking rumble that filled my room on the opening synth notes of “O Vazio” (from Reference Recordings Jazz Kaleidoscope (CD) shocked me. I didn’t know the M3’s could do that! This low-end prowess did great things for the realism and impact of all kinds of drums and percussion. It also clearly delineated the notes of bass guitar lines that I felt obscured by lesser amps (such as Verdine White’s ever-tasty plucking for Earth, Wind and Fire), but when powered by the Luxman, such proved easy to follow. In general, music with strong rhythmic content gained new, propulsive energy from the Luxman L-550AXII’s nimble low-end.

Truth and Excellence

The amp also had a way of bringing out the best in some recordings that had always impressed me as indifferently engineered, at best. Emerson Lake & Palmer, among the musical idols of my high school years, were about nothing if not shameless bombast, and “Tarkus” from The Essential Emerson Lake & Palmer 3 CD set sounded appropriately overblown and self-important, serving this progressive, “arena rock” music perfectly. “Right Down The Line,” a hit from Gerry Rafferty’s City To City LP, had vocal presence and soundstage depth that I hadn’t heard before.

And yet, the Luxman refused to sweeten truly putrid 1980’s pop recordings. For example, a miserably mastered, discount-bin Bangles greatest hits CD was still thin, harsh and nearly unlistenable. This amp speaks the truth.

Vocal power

Besides piano (and for some bass junkies, pipe organ), the reproduction of the female singing voice is a common touchstone of hi-fi performance. In this area, the Luxman acquitted itself admirably. On Be OK, Ingrid Michaelson’s voice is close and “dry,” with no reverb. The nuances of her technique on “Lady in Spain” were beautiful; I startled at the presence of her voice, and at the dynamic shift that emerged as bass, drums, accordion, and mandolin joined the instrumentals. Wonderful!

Got scale?

What the Luxman did with orchestral music was impressive. The last two sections of the Mussorgsky-Ravel “Pictures at an Exhibition” (from the Reference Recordings Tutti! anthology CD) sounded appropriately thunderous and dynamic. Also, these tracks displayed the Luxman’s ability to unravel complex passages at high volumes (“high” by my paranoid-about-my-middle-age-hearing standards) without congealing or glossing over instrumental lines.

Luxman and headphones

Just a few words about the headphone section. I’m not a big headphone guy. I have an iBasso DX-80 DAP and some terrific KEF IEM’s for on-the-go listening, but sitting tethered to the stereo wearing full-size cans isn’t part of my routine. However, for this review, I pulled out my pair of barely used NAD VISO HP-50’s, and they sounded fantastic connected to the Luxman L-550AXII’s headphone jack. I’d have to assume that the sound quality would scale upward with even better cans.

Vinyl Me

I must also mention the Luxman L-550AXII’s terrific phono stage. On LP after LP, the Luxman made my SOTA Sapphire with Ortofon 2M Blue cartridge sound better than ever. Tone and timbre were spot-on. The soundstage, depending on the recording, was huge in width and cavernous in depth, with reduced surface noise and silent backgrounds. Luxman says that the essential circuit design of the phono stage is identical in all Luxman integrateds, although parts quality climbs as you go up the ladder. LP spinners will love this thing!

Luxman L-550AXII

In Sum

I think the Luxman L-550AXII is an excellent amp. The $5500 isn’t cheap, but the quality of the workmanship, the pleasure and convenience of having the heart of your system contained in a single chassis, and the inclusion of a killer phono stage (and comparing that to the cost of separates of equal quality) the value of the L-550AXII is quite impressive.

Highly recommended!

Check out the following from Part-Time Audiophile:

  • Enter the Luxman: L-590a II Integrated Amplifier (review here)
  • Joseph Audio Pulsars revisited with Luxman L-505u Inte-grrrrreat-ed (review here)

Specifications: Luxman L-550AXII

Rated output 20W + 20W (8Ω), 40W + 40W (4Ω)
Input sensitivity / input impedance PHONO (MM): 2.5mV/47kΩ
PHONO (MC): 0.3mV/100Ω
LINE: 180mV/47kΩ
BAL.LINE: 180mV/55kΩ
MAIN-IN: 450mV/47kΩ
Output voltage RECOUT: 180mV, PRE OUT: 1V
Frequency response PHONO: 20Hz to 20kHz (±0.5dB)
LINE: 20Hz to 100kHz (+0, -3.0dB)
Total harmonic distortion 0.007% or less (8Ω, 1kHz)
0.02% or less (8Ω, 20Hz to 20kHz)
S/N ratio (IHF-A) PHONO (MM): 91dB or more,
PHONO (MC): 75dB or more
LINE: 105dB or more
Volume adjustment New LECUA1000
Amplification circuit ODNF 4.0
Output configuration Bipolar parallel push-pull
Damping factor 200
Max. amount of tone control BASS: ±8dB at 100Hz
TREBLE: ±8dB at 10kHz
Power supply 230V~(50Hz) / 115V~(60Hz)
Power consumption 230W
170W (under no signal), 0.5W (at standby)
External dimensions 440(W) x 178(H) x 454(D) mm
front side knob of 20mm and rear side terminal
of 27mm included in depth
Net weight 24.3kg (main unit)
Accessories Remote control (RA-17A)
Power cable
Speaker terminal Supported Y-lug terminal dimension Width of part a: 15mm or less
Width of part b: 8mm or more
* Connection may not be performed
depending on the shape of the
Y-lug terminal.

About the Author

Steve Folberg is a native Philadelphian who clearly remembers buying his first LP (Chicago Transit Authority) at the age of 12. He became fascinated with stereo gear shortly thereafter and has remained so ever since. His first “real stereo system” included a Technics by Panasonic 12 watt/channel receiver, a Technics direct drive turntable and a pair of Epicure 10 monitors. He has taken lessons on an embarrassing number of musical instruments over the years. As a high school trumpet player, he was devoted to the music of Blood Sweat & Tears, Chicago and the late, great Maynard Ferguson. He is also forever in love with all things Steely Dan.

Steve has his own little audio blog which debuted by documenting the entire build of an Audio Note Kits “Kit 1” 300B SET amp. New posts are still added “as time permits.”

In addition to the joys of being a husband and dad, Steve is blessed to be the Senior Rabbi of a truly wonderful congregation in Austin, Texas.




4 Comments

  1. Luxman gear has always been too underrated and it lasts. Good to see it getting more reviews. 1st Rabbi high-end reviewer. Kosher Ian thinks that’s pretty great.

  2. Hi Steve, I’ve been reading your blog for some time now, nice to see that you are contributing to PTA. The Carver Sonic Holography gimmick reminds me of a Hughes SRS box I used to have.

  3. Our musical tastes are hauntingly similar (I think CTA was my first album too), and I played trumpet through college, but I’m not a rabbi or jewish. Oh, and I still have a System Dek IIX turntable w/glass platter.

    My experience with a Luxman integrated was when Phillip O’Hanlon demo’d one for the Las Vegas audio club in my home. It was sublime.

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