Luxman M-700u Stereo Power Amplifier
M-700u, a power amplifier, is a new middle range model that inherits our powerful drive circuit including the latest version, ODNF 4.0 circuit whose distortion characteristics and S/N performance have been significantly improved and with which the top-end model, M-900u, has been equipped and also including 4-parallel push-pull structure with 3-stage Darlington to pursue Luxman's development philosophy for power amplifiers, "satisfying both high drivability and sound quality of high density". The output from 120 W/8Ω to up to 840 W/1Ω instantaneously exploits the full potential of speaker characteristics under any load conditions. M-700u is a new-generation stereo power amplifier that combines richly expressive sound and high power without losing the music dynamism.
High-power 4-parallel module, ODNF circuit, version 4.0
A powerful drive circuit is necessary to amplify sound signals from a control amplifier with high fidelity and to exploit the performance of various speakers. M-700u has achieved the output of up to 840 W + 840 W (1Ω) instantaneously from the rated output of 120 W + 120 W (8Ω) and 210 W + 210 W (4Ω). Speakers can be driven with its sufficient power under any load conditions. Moreover, the BLT mode allows the user to use the unit as a monaural amplifier with the rated output of 420 W(8Ω). A 4-parallel push-pull structure with 3-stage Darlington is used in this circuit to acquire such high power. The latest version, ODNF 4.0 circuit, that has achieved primary slew rate speed indicating the startup performance by feeding back only distortion components, ultra-wide bandwidth, and low level of distortion is adopted for the amplifier circuit, which is inherited from M-900u, our top-end model. Precise reproduction of a small sound signal has enhanced the elaborate sound expression and the expressive capability of tranquillity. Setting up to 6 W with which sound range can be practically and sufficiently acquired to the Class A operation range, it has made its high power consistent with sound expression of high density.
* ODNF is an abbreviation for "Only Distortion Negative Feedback".
Large-capacity power supply circuit
M-700u is equipped with high-performance EI type power transformer whose rated capacity is as much as 550 VA with a reputation for its tone quality full of dynamism including bass range perseverance to support overwhelmingly powerful power supply unit. A high level of regulation ability that is unshakable by any load fluctuation has been achieved.
Low impedance transmission
In order to transmit the powerful drive force generated by the large-scale output circuit without any loss, super-thick wires for major current systems and large-capacity speaker relays with low resistance in which 4 contacts are connected in parallel are equipped. Transmission of thoroughly low impedance has been achieved, and 350 of the damping factor has been accomplished.
Large-capacity block condenser
The combination of block capacitor with high-capacity of 80,000μF (10,000μF x 8) whose right and left channels are independent and a power transformer configures high-inertia power supply that offers both instantaneous force and a sense of stability. This unit supports the performance of M-700u from the bottom and delivers the sound dynamism amazingly.
|Rated output||120W + 120W (8Ω)/at stereo
210W + 210W (4Ω)/at stereo
420W (8Ω)/at monaural
|Instantaneous max. output||840W + 840W (1Ω)/at stereo
1,680W (2Ω)/at monaural
|Input sensitivity||1.1V/120W (8Ω)
|Input impedance||Unbalanced 51kΩ
|Frequency response||20Hz to 20kHz (+0, –0.1dB)
1Hz to 130kHz (+0, –3.0 dB)
|Total harmonic distortion rate||0.009% or less (1kHz/8Ω)
0.1% or less (20Hz to 20kHz/8Ω)
|S/N ratio (IHF-A)||115dB|
|Amplification circuit||ODNF 4.0|
|Output configuration||Bipolar 4-parallel push-pull|
|Power transformer||EI type 550VA|
110W (under no signal)
0.4W (at standby)
|External dimensions||440(W) x 190(H) x 427(D) mm
front side knob of 2mm and rear side
terminal of 38 mm included in depth
|Accessories||Dedicated remote cable
|Speaker terminal Supported Y-lug terminal dimension||Width of part a: 14mm or less
Width of part b: 7mm or more
* Connection may not be performed
depending on the shape of the
* Reprint from Manufacturer's website