The Audioresearch Reference 750 SEL monoblock amplifier continues the story to create the ultimate, vacuum tube amplifier with enough power to drive any speaker, and to provide a musical experience unlike any before it.
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The Reference 750 SEL redefines all expectations of what is possible from an amplifier in a music playback system. It is the culmination of everything Audio Research knows about amplifier design and manufacture, High Definition in its purest, most dynamic form. Listening to Reference 750 SEL monoblocks in a high performance system is a transformative experience; under total control, speakers disappear from the listening room and the listener is transported into a three dimensional realm where music takes on a palpable, tangible form
Details from source material are resolved against a black background, painting images in space with vivid reality. Bass becomes the foundation on which this living performance develops, produced with startling temporal and timbral accuracy. Here is the breath of the performer, the pick against the string, the brilliance of a full orchestra. The Reference 750 SEL delivers over 750 watts of power into speaker loads of 4 to 16 ohms. This is achieved by the use of massive, custom built power and output transformer delivering current from sixteen KT150 vacuum tubes in each channel.
Thanks to 48 hours of burn in, followed by thorough testing and careful matching of tubes, the amplifier requires little maintenance. Power supply regulation is also achieved by 6550WE and 6H30 vacuum tubes. Tube bias is controlled by two KT150 tubes, each driving a bank of eight KT150 output tubes. The SEL is the last version of the 750 series, produced in a limited edition of ten pairs. Using the latest and best parts available, the SEL version includes 23 new wires and 26 new capacitors as part of a stunning sonic transformation. The best vacuum tube amplifier in the world just got better.
Power Output: 750 watts per channel continuous from 20Hz to 20kHz. 1kHz total harmonic distortion typically 0.5% at 750 watts, below .04% at 1 watt. Approximate actual power available at “clipping” 850 watts (1kHz). Note that actual power output is dependent upon both line voltage and “condition” i.e. if power line has high distortion, maximum power will be affected adversely, although from a listening standpoint this is not very critical. Weight: 170 lbs. (77.2 kg) Net; 395 lbs. (180 kg) per pair shipped weight. ■