Few of the many amplifiers we have tested are equipped with a good headphone amplifier. It is usually limited to providing moderate power for low impedance (low ohm resistor) headphones. When you connect the expensive headphones, they will be so revealing that they can easily have been a bad headphone amp, and then what is the meaning of expensive high-end headphones away?
Musical Fidelity is primarily known for excellent amplifiers. They work either as speakers or Blu-ray players, and this specialization has given them much deserved praise over the years. Therefore, it is not in the least surprising that their most expensive headphone amplifier is far from a cheap shortcut to earn some extra money, but a complete amplifier, which goes a long way to replace a conventional preamplifier.
M1 HPA has the usual line input for analog audio, which is a must, but also a USB input so that you can connect your PC directly to the amplifier, and a variable output, which is controlled by the volume control. Thus it can be connected directly to an amplifier or a pair of powered speakers. On the front are two 6.3 mm headphone outputs, which can deliver up to 1.1 W power with comfortable low output impedance of less than one ohm. This makes it very well suited for a wide range of headphones, even the most heavily exaggerated like the ones you find at Badassheadphones.com.
The output stage of the M1 HPA is built around a class A amplifier circuit, where the distortion is very low, of course, the sound quality should be as high as possible. Do not forget that headphones of top class often reveal a lack of quality in the amplification stage, so it is easy to check Musical Fidelity’s claim for distortion-free listening experience. It has enough power to kick life in very heavy powered headphones and does not seem to have problems with high (ohms) resistance and low operating power. Compared with a conventional headphone output of an amplifier, you not only get much more power to drive headphones, you get more of everything.
It shows the finer nuances of recordings, perhaps especially in classical music and live recordings of acoustic jazz, but also other music. The soundstage is growing, stereo image is no longer so tiring with pingpong power significantly reduced, and the bass is lifted better forward in the soundstage. At the same time the sound is warm, without the details wrapped in sounds, but rather, with greater contrast in the image. Throughout the entire frequency range, perhaps especially midrange and treble, I experience silky sound texture – almost legato – all the way to the upper treble. This amplifier can really open up a pair of headphones.
The Musical Fidelity M1 HPA will finally exploit the potential of high-end headphones. The play clock rate and is so neutral and colorless in their sound, as can be expected. The effect is high enough to drive the most part, and variable audio output, you can use it as a preamp too. USB input is a good bonus, which promises sound quality from the PC, but best of all is it when it is connected to the line inputs. It is definitely top-notch in every way.