Luxman introduced the L-550A and L-590A in 2005—since then we have celebrated our 80th anniversary with commemorative components that have reaffirmed Luxman’s status at the pinnacle of high-end audio. In these latest integrated models, the gorgeous texture and three-dimensional performance of our original Class A amplifiers have been retained and further refined. For example, the amplifiers feature a new electronic selector switch, adopted from the input section of the C-1000f control amplifier; the internal circuitry has been revised to include customized OFC wiring and a high-speed Schottky barrier diode has been selected for the power source section—improvements that have notably enhanced the sound quality for greater musical enjoyment.
The Luxman L-350AII is a rebadged L-550AII with all the critical Japanese audio parts, sourced from Luxman in Japan but assembled in China. As a result we were able to lower the retail price from $5000 to $3500 – a 30% decrease.
Loopless chassis bases have superb vibration absorption in order to suppress noise levels. The power transformer, electrolytic capacitors and amplifier output stage (see amp block below) are laid out so as not to interfere with each other. To reduce interference further, the block construction isolates each section using shielding panels, and extensive internal filtering to reject magnetic flux interference.
Luxman holds many patents for audio engineering, amongst them is the application of Global Negative Feedback to the output stage, which while widely used throughout the audio industry, they no longer use themselves.
Luxman nowadays use a distortion reduction circuit called Only Distortion Negative Feedback (ODNF). This system works by isolating noise and distortion at the output from the music signal and sparingly applying negative feedback to suppress them. Conventional negative feedback systems can have an adverse effect on the music, introducing phase distortion. “The circuit features such an ultra-wide range, ultra- high slew rate and ultra low distortion that it does not use phase compensation for the music signal amplifying circuits.” This new technology also ensures that need for a DC servo circuit is alleviated, again improving sound quality.
Pure Class A
Thanks to the always-on nature of the topology and the removal of an entire type of distortion, allied to sound that excels in a midrange liquidity, low-level detail, superb dynamics and transparency, its devotees are more than happy to put up with low efficiency and heat. What Class A always seems to offer above everything else is a tube-like sound without the maintenance hassle of tubes.
The power supply was beefed up, the L-550A used to consume 160W of electricity, the L-350A II has raised this to 190W; delivering more drive and a firmer grip over your loudspeakers.
The L-350AII and the L-550AII feature the new high quality electronic selector switch, which is the heart of the C-1000f pre-amp (one of Luxman’s 80th anniversary commemoration models). The sound quality deterioration using the new electronic input switch is now minimal, while channel separation and crosstalk efficiency were raised substantially in comparison with the previous L-550A / L-590A. In addition the illuminated position indicator around the input selector knob, makes it much easier to view the selected position even from afar.
Electronic Volume Control
The integrated amplifiers have a motorised volume control, addressable from the remote control. The less devices in the signal path, the purer the sound, the cleaner the music.
The amplifier section has not been ignored either; noise and distortion has been kept to a minimum with the introduction of ODNF version 2.2A. The deep, rich Class A tone is available here in Luxman’s entry level Class A integrated amplifier.
Pure Copper Cabling
Extensive listening was applied to the high purity, oxygen free copper (OFC) cables which are used to transmit the signal throughout the amplifier. These cables have a minimal audible signature and minimal electrical effect on the audio waveform. Linear wide bandwidth frequency response is achieved by the low measured values of both inductance and capacitance. The result, the cables do not color the sound, but pass it through, quickly.
Enjoy the ability to play or record your LP collection with the built-in phono stage which accommodates both Moving Magnet and Moving Coil cartridges. The MM input has approx. 35dB of gain. While the MC input has 55dB of gain (that’s a multiplication of 550x). We recommend MC cartridges with an output >.25mV. Lower than that you might consider using the MT-88 moving coil step-up transformer. Click here to be redirected.
A subsonic filter is also easily accessible on the front panel in order to remove unwanted low-frequency noise while you are listening to a record. When the stylus hits the groove, you might notice the woofers modulating in and out, even though there is no music playing yet. This is due to the ultra low-frequency information (below the music), this unnecessary information places a strain on the amplifier and is best filtered out. A mono switch is also available for both loudspeaker setup as well as mono record playback.
There is also a high quality headphone amplifier, accessible from the front panel, ideal for late night listening. You can turn off the speaker output by a simple click of the Speaker Selector.
Two Pairs of Speaker Terminals
Large speaker terminals for driving two individual sets of speakers. At the turn of the speaker switch, it is possible to change between the two pairs of speakers easily. In addition, if the A+B function is used; Takasina capacitors are used to parallel the output which permits bi-wiring a single pair of speakers.
The large-sized power meters, calibrated in decibels are easy to read even from a distance. The logarithmic compression system is easy to grasp and also how this applies to the music. The meters are calibrated from -60dB below full rated power to +3dB above rated power. An 8mm thick acrylic covers the meters, which are normally backlit, though the illumination may be turned off from the remote control.
Easy to use, intelligently laid-out, aluminum remote control; all of the primary functions of the L-350AII and L-550AII, including power on / off can be controlled from the comfort of your listening chair. Besides the electronic volume control, there is also a mute feature. The display meters’ back light can also be turned on / off from the remote control.
The tone controls might seem like an anachronism in this day and age of minimalism, but they can be remarkably effective in bring to life a less than perfect music collection. We all have music gems in our collection that are sonically challenging. A lot of the 1980’s CDs are quite harsh sounding and the digital glare can be quite fatiguing. Reduce the treble slightly and while the harsh CD is not going to suddenly sound like a reference recording, at least it will now be perfectly listenable. Sit back relax, enjoy the music & forgot about the Hi Fi. When you want to bypass the tone controls, just engage the Line Straight switch.
NOTE: You might also use the Tone Controls for room acoustics’ correction. They are in effect simplified room equalization controls.
Line Phase Sensor
Here is a clever device found on the back of every Luxman powered product. You press the button and it will check the phase of the electricity it is receiving. If the AC outlet in the wall is incorrectly wired, meaning the live and neutral are swapped, a red LED will turn on to warn you. You only need to press it once, when you are installing a product to check that everything is in order. It’s a simple mistake, that occurs often, and one that can seriously undermine your listening enjoyment.