MRes Ultra MREU30 Folienwiderstand

Mundorf MRes Ultra MREU30 film resistor

Mundorf’s finest audiophile film resistor for the signal path, with a tolerance of ±1%.

The MRes Ultra resistors have been developed based on the well-known superior sonic qualities of copper-manganin film. Compared to all wire-wound resistors, this foil exhibits inductance that is several orders of magnitude lower. Copper is significantly softer than the metal oxide used in MOX resistors.

The natural resonances of the copper-manganin foil are therefore much less pronounced, meaning that distortions caused by crystallographic and electroacoustic factors are significantly reduced. Consequently, resistors of this design have secured a leading position amongst audio components in recent years: they are free from many of the distortions characteristic of other resistor designs.

For the MRes Ultra, in collaboration with a specialist in high-quality laboratory resistors, the most acoustically balanced resistors were first identified from a wide range of film and foil resistors to serve as the basis for further development.

In a further, very extensive development cycle, the micromechanical-electroacoustic distortions caused by feedback from electromechanical vibrations and microphony were minimised. To achieve this, the mechanical structure of the resistor was dampened against micro-vibrations, amongst other measures, by using heavier and more inert copper instead of aluminium as the carrier plate.

A whole range of adhesives and insulating materials were tested from a micro-acoustic perspective and optimised in combination, so that the overall micro-electro-acoustic distortions of the MRes Ultra are significantly below the level of other resistors available on the market.

As a result, significantly fewer musical details are lost in the microdynamics of the electrical signal. The subtle nuances of typical instrumental characteristics, the richness of timbre in the human voice and the lifelike staging of the musical performance can be experienced with the MRes Ultra in a purity that remains unrivalled to this day.