Grun.
Grun Coherent Earthing System.
The benefit of an independent system earth.
One of the biggest obstacles to achieving the performance levels our equipment is capable of is noise. Low levels of RFI (radio frequency) and EMI (electro-magnetic interference) and noise on the signal ground all subtly modulate and degrade the overall noise levels of the system.
Ironically, this is generally only noticeable when eliminated – even though much of this ‘noise’ is theoretically at frequencies beyond the range of our hearing. The main sources are noise in the mains supply and component ground connections – mobile phones, ‘wallwart’ chargers and wifi networks are major offenders – while a percentage is actually generated within the equipment itself. Generally things have got worse with the advent of computer audio.
The Grun Coherent Earthing System addresses these issues by providing an ‘independent’ earth for users of Mavros and Asimi Ultra interconnects and Mavros speaker cables* with the new Grun configuration.
![Atlas Asimi with Grun adapters](https://www.atlascables.com/assets/images-featured/hero-grun-panel-asimi.jpg)
MAVROS ULTRA RCA INTERCONNECT WINS HIFI NEWS ‘PRODUCT OF THE YEAR’ AWARD
![HFN Editor's Choice](https://www.atlascables.com/assets/images-reviews/hfn-editorschoice.png)
Our latest generation Mavros Ultra and Asimi Ultra interconnects and Mavros speaker cables with ‘Grun’ compatibility offer a further step forward with clear performance gains (the cable specification is otherwise unchanged).
![grun](https://www.atlascables.com/assets/images-vector/grun-coherent-320.png)
*Speaker cables are part of low impedance circuits and as such are not as susceptible to electrical interference as analogue interconnects. However, speaker cables often radiate interference, consequently it is good practice to ground the screen if available to minimise any ‘antenna’ affects.
Grun interconnects are easily identified by the blue-green Ultra RCAs (interconnects) and ‘flying’ earth connectors.
Asimi/Mavros Ultra Factory Upgrade
The great news for existing owners of the Ultra versions of the Asimi and Mavros interconnects is that can be factory upgraded to incorporate the Grun Coherent Earthing System. Please contact Atlas direct for more information.
Getting Started: Basic Configuration
![grun-default-amp](https://www.atlascables.com/assets/images-vector/grun-amp-default.png)
Mavros and Asimi interconnects are now configured with a flying ground lead on each channel. A basic Grun adapter is supplied as standard with these cables, and should typically be connected to a spare RCA input socket on your amplifier.
Getting Started: Speaker Cable Basic Configuration
![grun-amp-speaker-ground](https://www.atlascables.com/assets/images-vector/grun-amp-speaker-ground.png)
Why ‘earth’ a speaker cable?
Generally speaking, loudspeaker cables don’t potentially pickup interference in the same manner as an interconnect, but they may ‘broadcast’ interference, effectively acting as an antenna. In today’s extremely (electrically) noisy world, it’s important to minimise the adverse effects of noise on system performance – this can be addressed very effectively by providing a grounded screen on the cables.
Mavros speaker cables are now configured with a flying ground lead on each cable. Grun termination should be made to the amplifier’s ground terminal via 1–1 (×2) or 2–1 spade adapters.
Add an Adapter: Optimum Configuration
![grun-amp-ground](https://www.atlascables.com/assets/images-vector/grun-amp-ground.png)
The preferred configuration is to create a direct ground, either to the ground terminal on your amplifier (if fitted) or via a Grun mains adapter to a spare socket on your mains distribution block.
Warning
![electrical-hazard icon](https://www.atlascables.com/assets/images-extras/electrical-hazard.png)
Please not that the Atlas Grun topology is intended for audio signal earth only. Grun products are not to be used as a replacement for the ‘safety earth’ facilitated by the original equipment manufacturer and in no circumstances should you use these connections for sole earthing of any type of equipment connected to the mains power supply.
![Atlas Mavros with Grun adapters](https://www.atlascables.com/assets/images-featured/hero-grun-panel-mavros.jpg)
Grun Configuration Options
![pseudo-balanced](https://www.atlascables.com/assets/images-vector/grun-configuration-pseudo.png)
Pseudo-balanced
connected to spare RCA input via Grun RCA – female adapter
![earth via ground adapter](https://www.atlascables.com/assets/images-vector/grun-configuration-ground.png)
Independent Ground
Grun adapter connected via amplifier ground tag or Eos Modular 4.0 ground
![earth via power adapter](https://www.atlascables.com/assets/images-vector/grun-configuration-power.png)
Independent Ground
Grun cables connected via power adapter to system ground
![power adapters](https://www.atlascables.com/assets/images-vector/grun-power-adapters.png)
Grun power adapters are available in Nema, Schuko & UK 13A versions.
Your local Atlas dealer/distributor will normally supply Grun power adapters with the appropriate plugs for your country.
The Eos Modular 4.0 distribution block has an additional ground post designed to accept a Grun spade adapter. Alternatively. a Grun power adapter may be utilised in a spare socket on your mains block
![eos modular mains block](https://www.atlascables.com/assets/images-vector/tech-eos-uk-600.png)