With the presentation of the REF10 SE120, a 10 MHz reference clock generator, MUTEC claims nothing less than the technological as well as audiophile top position within this device category for itself. Strong words – we want to see if this is followed by corresponding sonic deeds.

When I read this announcement in MUTEC's press release, I was skeptical and curious at the same time. Skeptical, because I had reviewed the "normal version" of this clock generator, the REF10 , intensively some time ago. The qualities of the REF10 and especially the sound experience achieved had really excited me at that time and I could not imagine how at first sight rather slightly improved phase noise values should still top this. Curious, because I found Mr. Peters, managing director of MUTEC, as an extremely competent partner from many discussions, to whom the otherwise often usual marketing blah-blah-blah is quite foreign. He prefers to argue with hard technical facts. As so often curiosity prevailed, and the end of the story was that both the REF10 and the new REF10 SE120 ended up in my listening room. But what are the differences between the REF10 and REF10 SE120? Both devices are externally and technically identical except for the oscillator used. Already during the development of the REF10, MUTEC had realized how important the choice of the central oscillator is, and that its quality determines the technical and acoustical end result of a reference clock generator to a considerable extent.

The "tuning" version of the REF10 SE120 therefore offers an even more elaborately manufactured and selected oven-controlled crystal oscillator (OCXO). With the help of highly specialized and cost-intensive measuring technology, individual specimens of the oscillator are selected from larger production quantities. These have extremely low phase noise values of at least -120dBc measured at 1 Hertz offset from the carrier frequency of 10 Megahertz and clearly surpass the basic REF10 model (-116dBc at 1 hertzt) in this key aspect metrologically unambiguous.