When it comes to amplifiers, there have always been two construction principles: Tubes and transistors. While tubes produce a captivating euphoria, because the technology used enables them to add harmonic overtones to the music signals, transistors deliver brute power to drive even the most demanding speakers.
Tube amplifiers, or rather tubes in the audio sector, have an inherent flaw. This, however, is an extremely pleasant flaw. They produce harmonic overtones. This means that a signal of 1,000 Hz is also reproduced with harmonics of 2,000 Hz, 3,000 Hz and so on. In doing so, the harmonics are naturally much quieter than the actual sound. The ears perceive these harmonics as being very pleasant. The disadvantage of tubes, however, is that they are neither particularly powerful nor particularly efficient. This means you cannot really coax a lot of output power from them.
This is where the tried and tested transistors come into play. They are able to produce an impressive performance with an unadulterated sound, provided that you choose the right models of course. For these reasons, two ECC 81 tubes are used in the preamplifier of the MA 900. These are selected prior to installation. This ensures every MA 900 is equipped with two tubes that are perfectly identical in terms of their values. In addition, the tubes are also "burned-in" before installation. This is a process that takes several hours, during which the ECC 81 tubes are able to reach their final performance values. This ensures MA 900 is capable of producing the sound for which good name stands - as soon as it is unpacked.
Audiophile qualities are only part of what´s required today. 5 analogue low-level inputs and an additional jack input at the front of the unit offer sufficient connection options for all manner of audio equipment. The optical and coaxial digital inputs also support high-res audio with a sampling rate of up to 192 kHz and 24 bit. In addition, the MA 900 also comes complete with Bluetooth functionality. The state-of-the-art chip supports Bluetooth 5.0 and the high-end audio standard aptX®HD, thereby enabling optimum quality audio transmission from smartphones, tablets and laptops.
Vinyl is by no means neglected either. The phono preamplifier, which offers separate inputs for MM and MC systems, has been constructed with extremely high-quality operational amplifiers from Texas Instruments. The "Source Gain" function allows all of the inputs to be increased or decreased in terms of level by up to 6 dB, so that jumps in volume can be avoided when switching inputs. In addition, the inputs can be individually named by using the "Source Rename" function, meaning that the days of cryptic abbreviations are a thing of the past.
The MA 900 naturally has typical grid dimensions and measures 433 mm wide, which enables it to be perfectly combined with other components. The sturdy solid metal housing provides a robust framework for the high-quality electronic components. The solid aluminum front panel and operating elements are made to last and convey the feeling of quality with every touch.
This is also reflected by the components inside the unit. An elaborate power supply unit, generously dimensioned capacitors and a low-leakage toroidal transformer, together with the rest of the electronics, add up to a weight of almost 12 kilograms.
