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Blog-zine / Reviews / Hifi & Musik Journal: “MU1, Nothing is more beautiful than naturalness”

Hifi & Musik Journal: “MU1, Nothing is more beautiful than naturalness”

January 31, 2020

We are proud to let you know that yet another enthusiastic review of the MU1 is published. Joachim Pfeiffer of the German Hifi & Musik Journal printed magazine gave it ‘5 stars’! We took pleasure in translating part of his story to English:

“Most audio components on this globe are almost self-explanatory: a quick look at the device and its controls, as well as connections on the back, and the connoisseur can tell the function and often the quality level. Exceptions confirm the rule and the most exciting one that I have come across in recent years is probably the Grimm MU1 from the neighboring Netherlands.

(…)

Hardware and in particular the software of this stroke of genius, which Grimm developed in-house, serve only one purpose: to simply switch off external influences tutto completo and to pass on the signal with the greatest possible “purity”. One of the main enemies of digital music processing is the so-called “jitter”. These “digital timing fluctuations” damage the structure of music. In the MU1, the signal is rebuilt in such a way that a mediocre or even “bad” source – as delivered by a questionable CD drive – is raised to reference level. It goes without saying that Grimm uses its own high-precision clock. Next comes upsampling. If word widths of conventional 16 bits are supplied, the MU-1 increases them to 24 bits, from 44.1 kHz it conjures 176.4 and from 48 kHz 192 kHz. Can you hear that? The honest answer is: in principle yes, but not always with the same intensity. In “Across the Stars” with Anne-Sophie Mutter and John Williams (Deutsche Grammophon), from Tidal in “Master” MQA 96 kHz quality, rather less. A direct comparison to the Elac Discovery with Accuphase DP-560 as converter almost resulted in a stalemate situation for the Grimm / Accuphase team: in both cases it was a captivating recording that explores the dynamic limits of the hi-fi system.

But the less “perfect” the streaming files were, the more important the work of the MU-1 was. That even led me to listening to productions that I no longer want to hear on the Elac – because the structure in the music seems to be disturbed or even destroyed. In particular, I noted this effect on classical music: piano keystrokes, in particular the expression in the rise and fall of the tone, can offer unique, emotional moments. If they are changed by even a tiny nuance, the illusion gives way to disillusionment. You do not need bat ears or decades of listening experience to hear this, anyone will notice it in the comparison. And you get used to this sound quality very, very quickly. It is only when a component with true reference strengths leaves the test setup that you realize how good it really is. 

Since I have never heard streamed music of any genre better, more authentic and more breathtaking, I would like to pay my utmost respect to the people responsible for designing the Grimm MU1. Those who can afford it will live a happy life with it. It achieves the performance of the very best CD players. This is how fairy tales come true.”

Read about MU1 >

“I would buy it immediately if I could afford it”

Joachim Pfeiffer, Hifi & Musik Journal
Hifi & Musik Journal Grimm Audio MU1 review pdf (in German)
Read more about: Reviews · Grimm MU1 · Hifi
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Joachim Pfeiffer, Hifi Musik Journal, Wuppertal (MU1)

I have never heard streamed music of any genre better, more authentic and more breathtaking.

Joachim Pfeiffer, Hifi Musik Journal, Wuppertal (MU1)
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Designed & made in the Netherlands

Designed & made in the Netherlands

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