Luxman MB-3045 Tube Monoblock Amplifiers

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For your consideration is a classic pair of original, unmolested, Luxman mono-block amplifiers.

This is the last set we have out of the three we originally listed.

The 3045 is a classic tube design capable of incredible detail, authority, and holographic imaging.

These are both in beautiful condition with very little signs of use. I've tested them thoroughly at full power without any issues or hiccups. The tubes were all tested on our modern and professional Amplitrex tube tester and passed with flying colors.

These amps also use the desirable and original Luxman/NEC tubes and have not been converted to KT88's. These tubes are highly sought after.

Many feel the MB-3045 sounds way better that the McIntosh MC30’s and outperform them in every way. These were designed by the famed engineer Tim DeParavicini.

Both amps will be carefully packed to ensure safe arrival in their original boxes. All tubes will be labeled, removed and packed separately.

SkyFi Tube Notes:
All driver tubes are original Luxman branded 12AX7, 12AU7, and 6240G. The 8045Gs are a NOS (New Old Stock) set sourced directly from Japan.

TECHNICAL DETAILS From the amazing Vintage Knob Website so you're know these are really something special!
High-end tube amplifier representing Luxman's heyday in the mid 1970s which quite probably existed in fifty slightly different versions and also had LuxKit equivalents.

Primary is made of four windings wound together to reduce leakage and distortion inherent to Class AB or Class B amplifiers ; the GX100-3.6 transformer can deliver more than 35W at 35Hz.

8045G power triodes
Specially developped in collaboration with NEC.
In Class B, the power dissipated on the plate can amount to 60W at 1Khz, thanks to its structure and high heat-dissipation metal.

Push-pull stage
Made of two 8045G triodes on which a negative feedback loop is applied.

DC driver stage
Of the cathode-follower type, uses newly developped 6240G double-triodes.

Pre-driver
To rise the gain obtained by the driver stage, another 6240G double-triode is used here, with a 200V tension applied to the plate. A 5dB NFB is applied between the cathode and the 4th winding of the output transformer.

Differential amplifier
Its first stage uses a 12AX7 (ECC83) double-triode ; the second stage, DC-coupled with the first, gives an out-of-phase signal which is sent to the driver stage.

Power-supply section
GX100-3.6 Quadra-Filar output transformer (specially developped for the 8045G), C1744 low resistance choke self, two 220µF electrolytic caps.
After this stage, the filtered tension is applied to a bridge rectifier.

The Luxman MB-3045s are relatively compact, measuring just 8.5 inch deep, 14 inches wide and 6 inches tall. The front panel has only a bright-orange power indicator (the lit vacuum tubes also indicates that the juices are flowing). Around back, the configuration is relatively Spartan: a simple barrier strip for speaker output, with 4-, 8-, and 16-ohm taps, a solitary RCA input jack and a level control, along with a two-prong power cord receptacle.

The SkyFi Testing Process for Tube Amplifiers:
We start with a visual inspection of all internal components to make sure there are no signs of stress or aging. Capacitors are checked for telltale sings of bulging or leaking, resistors are checked for signs of overheating or cracking, and tubes are inspected for signs of stress overheating or cracking.

We then power up the unit carefully and run a simple 1k sine wave while monitoring the output on an oscilloscope for signs of distortion or noise. Finally we run the amplifier to its full rated power into the appropriate resistive load provided by our Sencore amplifier tester. If there is an issue, it will usually be noticeable at this point. If it all looks clean we will often test for THD (Total Harmonic Distortion) measured by our Keithley distortion meter, and compare it against the original manufacturers specifications. The amplifier the remains powered on to "burn in" on our test bench for a few hours to make sure there are no heat related issues. If there are balanced inputs available they will also be tested.

We also test all tubes for output gain and leakage on our calibrated B&K 747 tester against the original manufacturers specifications. If needed, the tubes will be replaced from our vast NOS (New Old Stock) vintage or modern inventory.

Final testing involves pushing actual music thorough the amplifier. We've learned over time that some issues are only noticeable to a trained ear while listening to familiar source material. Our test bench has reference vintage KEF speakers that we're very familiar with which quickly reveal any discrepancies. Some amplifiers will then move into our listening room where they are tested with our in-house reference speakers of choice.

Please click here for detailed specifics regarding our specialized packing process that separates us from the rest.