Luxman L-505u (2007)

Name: Luxman L-505U
Brand: Luxman

It hums when you power it up—not from strain, but from readiness—like a luxury sedan with a V8 idling behind a quiet grille.

Overview

The Luxman L-505u isn’t just another integrated amplifier from the 2000s—it’s the Ultimate edition of a lineage that’s been Luxman’s best-selling single product for over three decades. Released in July 2007, this isn’t some understated workhorse; it’s a statement piece wrapped in Blaster White or limited Champagne Gold, with glowing VU meters under thick acrylic that look like they belong in a high-end watch. It’s “Luxman’s entry-level but heavyweight integrated amplifier,” a paradox that makes sense the moment you lift it—20 kilograms of precision engineering packed into a chassis that feels more like a vault than a stereo component.

Don’t let “entry-level” fool you. This is the model that took the L-505 series and pushed it into flagship territory without actually being the top of the line. It’s the successor to the L-505f (introduced in 2001), but with a full overhaul: ODNF 2.2 circuitry, a motorized Alps potentiometer, and a phono stage that handles both MM and MC cartridges with authority. It’s designed for people who want a single-box solution that doesn’t feel like a compromise—something that can drive demanding speakers, handle vinyl with finesse, and still look like a piece of industrial art on the shelf.

Specifications

Manufacturer	Luxman
Model	L-505u
Year of Release	2007
Type	Integrated Amplifier
Continuous Effective Output	100W + 100W (8 Ω), 140W + 140W (4 Ω)
Total Harmonic Distortion	0.008% (8 Ω, 1 kHz), 0.04% (8 Ω, 20 Hz – 20 kHz)
Frequency Characteristic	Phono: 20 Hz – 20 kHz ±0.5 dB; Line: 20 Hz – 100 kHz +0 -3.0 dB
Damping Factor	110
Input Sensitivity / Impedance	Phono MM: 2.5mV/47kΩ; Phono MC: 0.3mV/100Ω; Line: 180mV/47kΩ; Bal. Line: 180mV/47kΩ; Main In: 1V/51kΩ
Signal-to-Noise Ratio (IHF-A)	Phono MM: 91 dB or more; Phono MC: 77 dB; Line: 106 dB
Tone Control Maximum Change	Bass: ±8 dB (100 Hz); Treble: ±8 dB (10 kHz)
Subsonic Filter	15 Hz (-6 dB/oct)
Power Consumption	190W (max), 82W (no signal), 1.2W (standby)
External Dimensions	440 × 156 × 428 mm
Weight	20.0 kg

Key Features

ODNF 2.2: The Heart of the Matter

The L-505u runs on Luxman’s ODNF 2.2 circuit—short for “Only Distortion Negative Feedback.” It’s not just marketing jargon. This design feeds back only the distortion component from the output, leaving the music signal untouched. The result? An amplifier that claims “ultra-wide range, ultra-high slew rate, and ultra-low distortion” without needing phase compensation in the signal path. That’s rare. Most amps need phase compensation to stay stable, but Luxman’s engineers tuned this one to run clean and fast without it. Whether you hear that in the sound is subjective, but the specs don’t lie: 0.008% THD at 1 kHz into 8 ohms is exceptional for a Class A/B integrated.

Class A/B with Muscle and Manners

It’s not pure Class A—those things run hot and thirsty—but the L-505u runs warm, not scorching, and delivers 100 watts per channel into 8 ohms (140 into 4). That’s enough juice for all but the most insensitive speakers. Reviewers have driven Magnepans and Joseph Audio Pulsars with ease, praising its “bombast and delicacy” in the bass and “copious air and sparkle” in the highs. The midrange? “Nailed,” according to one listener. It’s a balanced performance—never shouty, never reticent.

Phono Stage That Punches Above Its Weight

For a box this size, having a built-in phono stage that handles both MM and MC is a big deal. The MM input gives you 35dB of gain, the MC a healthy 55dB, with impedance switching right on the back panel. And it’s not an afterthought—reviewers call it “excellent,” with enough clarity and low noise (77 dB S/N for MC) to make it competitive with standalone phono preamps. There’s even a subsonic filter at 15 Hz to clean up rumble from warped records or turntable resonance.

Build Quality That Feels Like Legacy

This thing is built like a bank vault. Glass fiber circuit boards, OFC internal wiring, a high-capacity EI transformer, and a chassis layout that isolates the power supply, output stage, and sensitive preamp sections with shielding panels. The volume control? A motorized Alps pot, the kind you’d expect on a preamp twice the price. The input selector is a trickle-down from the flagship C-1000f preamp, using an IC-based electronic switch to avoid contact wear. And those meters—oh, those meters. Calibrated from -60dB to +3dB, covered in 8mm acrylic, glowing blue or yellow depending on the finish. They’re not just functional; they’re theater.

Tone Controls That Don’t Ruin Everything

Most high-end amps skip tone controls, assuming you’ll want a straight wire with gain. But Luxman included them—±8 dB at 100 Hz and 10 kHz—and they’re implemented well enough that you can actually use them without degrading the signal path. They’re not for drastic EQ, but for fine-tuning room anomalies or speaker voicing. And they’re defeatable, of course.

Historical Context

The L-505u arrived in 2007 as the “Ultimate edition” of a series that had already been Luxman’s sales leader for over 30 years. It replaced the L-505f, bringing modern refinements without losing the DNA of the line. It wasn’t the biggest Luxman—bigger models had larger power supplies and more headroom—but it was the sweet spot: a full-featured, high-performance integrated that didn’t require a second mortgage. It was also a bridge between eras, offering balanced XLR inputs and robust digital-era build quality while still catering to analog lovers with its dual phono inputs.

Collectibility & Value

As of its release, the L-505u carried a price of ¥225,750 in Japan—about $3,700 in 2009—and was considered a screaming bargain by Stereophile’s John Marks, who called it “addictive” and “sonic authority in spades.” Reviewers noted it outperformed even the $10,000+ Class A L-590a Mark II in some systems, preferring its balance and drive. One even said, “when compared to the $10k+ Class A Luxman L-590a Mark II, I dramatically prefer the $4k Class A/B Luxman L-505u.”

Today, it’s discontinued, succeeded by the L-505uX and later the L-505uXⅡ. Used units have been listed around $1,795, though prices vary by condition and market. It’s not a rare unicorn, but it’s respected—a “fantastic anchor for a high quality, no fuss, hifi system.” The build quality is identical to Luxman’s flagship models, and the phono stage alone makes it a contender for vinyl lovers. Just be aware: it was originally configured for 100VAC operation. Some units have been modified for 115V, but if you’re buying one, check the power supply setup—biasing may need adjustment for stable long-term use.