Steinmusic Ground Cube Silver Signature

One of the whatsbestforum.com commenters left the following message about SteinMusic’s Ground Cube: [It] is like replacing the water in an aquarium; suddenly everything is clear, no haze, no cloudiness left. Although it may seem like another typical audiophile hyperbole on an internet forum, the comment is actually very spot on. The Cube does it, and more.

Cleaning the water in my aquarium

The SteinMusic Ground Cube that I received for this review was a “Silver Signature” version. It is a small black box with 130×130mm footprint and 120mm tall. I expected something heavy and dense, but it is just above a kilo.

There is nothing but textured surfaces with a single gold-plated binding post to which the provided grounding connects with a hollow banana. The cable is a part of the game. It is braided from 61

individually insulated strands and wrapped in cotton braid. The other end is terminated with the same banana. Nothing else is needed as the Ground Cube is supposed to be connected to you main power distribution or filtering block. It usually comes with a grounding post that accepts bananas. If not, you can attach it to any bolt that is connected with the chassis ground or to free Schuko outlet -- a crocodile clamp and a Schuko plug are included the packaging.

Before you ask – no, I won’t tell you what’s inside. SteinMusic has been in business since 1982 and the company portfolio includes loudspeakers, amplifiers, phonos, vinyl cartridges, and many more products. They are an engineering-based company, rather than trial and error manufacturer. But of course, some trial and error is a part of the development. As Holger Stein puts it, the process for new products in SteinMusic is a lengthy one; not every day they have good results with what they think should work on paper. It takes months to re-iterate, validate and finalize the final offering. The gained know-how is certainly not something you’d put on the internet at everyone’s disposal. The Ground Cube is not expensive by high-end standards (less than 2k€ for its standard version) and nothing prevents anyone for having it demoed. Be ready for an ear-opening experience.

Bria

I have no idea where I got signed versions of Nothing Never Happens and Bria albums from. And why is there a heart hand-drawn on the sleeve? I wish it had a deeper meaning as Bria Skonberg is a gifted Canadian jazz singer and a trumpetist and a beautiful woman. I like how easy I am able to see into the recording ambience of Figure 8 Studio and the intimate and somewhat muffled production with the Cube; after all the Figure 8 recording room is more a well-damped living room rather than a reverberant acoustic space. This is in contrast with the Bria album which was taken in Sear Sound, NY, and is certainly more polished, reverberant, and produced. The SteinMusic Ground Cube as if erased all the hash that obscures subtle nuances and let the music and the air in the studios speak. How big the Ground Block contribution is can be appreciated especially in very soft parts, like the wonderful intro of Trust In Me, or not less wonderful outro of My Shadow, where silence plays an equally important role as the bass, the percussions, and the piano. The sounds emerge from a velvety thick background, previously a digital zero, now a backdrop where you feel how air shifts and how the electronics used to record the instruments hum. Again, compared to other similar [grounding] devices I am getting a heightened sense of being there and an amazing depth of image without the unwanted hi-resolution artifacts like etched transients, too much presence and forwardness, and – consequently – fatigue for ears. In this sense, I find SteinMusic’s own description of how the Ground Cube demonstrates itself completely competent.

In the past 12 months, I hosted in my reference set-up other two virtual grounding concepts: Diamond Sound’s E1 and E2 units and TweakGuru’s Horizonta Megas system. Each is great, each different. Diamond Sound units each have their own little way to shift the spectrum towards lush romanticism or airy precision, or anything in between, depending on how you combine them and how many. They are chunky, bold, and aluminium. Horizonta Megas provides many degrees of freedom as it is a highly tunable system, provided that you know what you are doing. Made from Panzerholz, they can wrap your system in a well-thought ‘grounding’ network. Each subtly shifts the sound spectrum in one or another way. The SteinMusic Ground Cube does nothing like that and out of the three it is the most flavourless.

I was listening to Ultravox’s 2000 re-issue of Vienna (EMI Gold) when I noticed how much the instrumental Astradyne grew with the SteinMusic Cube. The album was released in 1980 with the usual hotter top end energy to compensate for rather muffled sound of compact cassettes that were the playback standard of the time. The Ground Cube preserved the high-octane energy but made the sound better organized and less right-to-my-face without sacrificing the tinniest bit of transparency or dynamics. The presentation with the Ground Cube did not get warmer, fuzzier, or sweeter; the transients remained crisp and sound, the bass remained punchy and textured, but everything just got more relaxed and less irritating, while preserving the deepest layers of resolution including the faint buzzing of recording equipment that found its way into the synth track.

As mentioned, the SteinMusic Ground Cube Silver Signature is quite a lightweight apparatus. All virtual grounding units, with no exception, rely on the relationship between their size and weight and the size and weight of the piece of electronics that is to be grounded. It has something to do with the amount of active materials inside (usually rare earth mineral mix) and its saturation capacity. At least this is what they say. SteinMusic has not jumped on the same bus and – imagine – the whole audio system’s performance depends on a this mini-cube and it works as good as any sandbox-sized grounders.

Unlike the SteinMusic H2 Room Acoustic system that needs certain time to connect to the room and bloom in it, the Ground Cube provides most of its contribution right out of the box. Yet, it settles down and slightly improves in couple of days of being connected. So, if the H2 Harmonizers are like 20/80 in terms of the initial/stabilized ratio, the Ground Cube is 80/20. Still, exactly like with other grounding units that I tested, it is worth experimenting with where the unit is placed. The speakers and the electronics radiate often strong electromagnetic fields and even the passive units like this are sensitive to it. I usually end up with a clear marking on the floor with the direction of where the unit is pointing. The Ground Cube Silver Signature is not different. You even find a small compass in the packaging to help me with orientation of the unit. I cannot say whether the compass works a rule of thumb, because after I found the best spot for the Cube (interestingly it was very close to the place where my other passive grounding block ended up before), I let a track play on repeat and rotated the unit to identify the best sound balance.

The longer the SteinMusic Ground Cube stayed in my reference system, the more I appreciated the most important feature of it: the ability to delicately enhance the spatial cues, provided that they are encoded in the recorded material.  It is very hard to put in words what the Cube does. For example, take the way the bass, the vocal, the piano, the violin, and the shakers are captured in the realistic and spacious recording of Spanish Harlem (Rebecca Pidgeon, Chesky Records). Even without the Ground Cube it is a fantastic track. With the Cube, it was as if during the studio performance the lights went off and the musicians were only illuminated. The eyes are not distracted by décor of the studio and ears thus can better concentrate on how the music develops and wraps around the ears. The music gets very tangible and present, the voice and the instruments unambiguously locked in the space that is not defined by what you see, rather by what you reconstruct from ambient clues that surround the performers. Are you still with me? I don’t think so.

This is how the effect of the SteinMusic Ground Cube Silver Signature can be visualized.  

Wherever I May Roam from the last true Metallica album (Black Album) before the band went landslide towards weirdness was recorded as a short crunchy track to please radio stations who complained that the band composes too long songs for radio broadcast. The track base was recorded at One on One Studios in LA, but when the band was invited to Vancouver, they found inspiration in the instrument collection of local Little Mountain studio. Thus, the track got the intro of Hetfield playing Danelectro Coral, an instrument that emulated Indian sitar sound, while Hammet accompanied him with oriental-flavoured guitar solo. These additions are beautifully rendered with SteinMusic Ground Cube. The Coral acquires better depth of colour, at the same time more vivid and real and relaxing, and the track entagles me long before the rhythm guitar kicks in and the song becomes a thrash-fest. I am getting the same ‘be-thereness’ with strings and rolling drums that start Enter Sandman. These subtle transformations give the music fresh perspective.

To me, the SteinMusic Ground Cube Silver Signature is a deceptively simple accessory, that has the ability to focus the sound and build the image depth in the finest resolution. It works behind stage, does not affect the main character of the audio system, and exhibits itself as unforced and completely natural without adding or subtracting anything. It will not fix problems in your system, though. But if you really like how your audio system already sounds, add the SteinMusic’s Ground Cube. There is a high chance that you will hear your music like never before.

Associated components:

• Source: Accuphase DP-720 SACD
• Amplifier: TAD M2500 koncový zesilovač
• Interconnects and speaker cables: Ansuz Signalz C2, Velikinac Audio Synapse and Eonix, Signal Projects Andromeda, Next Level Tech NxLT Ether, AudioQuest Dragon Zero|Bass
• Loudspeakers: TAD Revolution One, Sonus Faber Gravis I, PSI Audio AAVA, Synergistic Research Black Box
• Power conditioning: Stromtank S-1000, Shunyata Research Denali, Ansuz Mainz8 D2, Ansuz Mainz C2, AAI Maestoso and Estremo, Synergistic Research Atmosphere Level 2, Nordost Qk1, Qv2, Qsine and QWave, Diamond Sound and TweakGuru Horizonta Megas grounding boxes

Up to date prices are available in SteinMusic online store: https://www.steinmusicstore.com

Contact: Stein Music Pro GmbH, Mülheim an der Ruhr, Germany, + +49 (0)208 32089

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