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FM Acoustics

The FM 255-MKII-R features a cute remote that allows the important functions to be controlled remotely. Handcrafted at FM ACOUSTIC'S Swiss facility it provides an additional great feature that is unique: slow and fast speed volume control.

  • The upper two controls "FAST" will cause the level to increase or decrease rapidly.


  • The lower two controls "SLOW" will cause a more gradual change of level, thereby allowing very precise audio level setting.



New switchable true-impedance attenuators - unique to FM ACOUSTICS -  are included on the balanced inputs. These are very useful with some of today's high level components (Download servers/CD/DVD players/converters etc.) that  deliver excessive voltages - often far above the standardized level ratings. Such excessive input levels can overload input stages (not the ones of the FM 255-MKII-R though...). They force the user to set the Level control on the line stage to very low settings, so low that it actually works as an attenuator instead of a pre-amplifier. The new input attenuator lowers such excessive levels whilst guaranteeing perfect balancing (not an easy feat). This in turn results in optimal Level control setting (around 12 o'clock position for normal listening levels).


To allow optimization of the total system gain - which differs widely from one system to another - further level switches allow tuning of the internal gain of the FM 255-MKII-R. This allows more flexibility in system gain optimization.

Any system can be set to an optimal gain structure - which improves total system performance.

"HR" Modules

The new "HR" modules are used on the inputs. They help to achieve an astounding 100dB of rejection of interference, hum, noise etc.) making the FM 255-MKII-R immune against disturbances.

This rejection is not achieved with cheap op amps but with a fine-tuned discrete Class A configuration which guarantees the phenomenal resolution FM ACOUSTICS equipment is world renown for.

TYPE 19200

The new "HR" type 19200 modules are employed for the true balanced outputs. These new "HR" modules are the result of a multi-year development.


They achieve a superb level of reproduction and reliability. Never before has such a level of accuracy been achieved.

Resonance-Eliminator Support

To avoid negative influence from spurious resonance and guarantee positive connection the FM 255-MKII-R employs FM ACOUSTICS' unique resonance-eliminator supports.

These isolate the unit from potential resonances which are absorbed.


Hand-selected precision Output Level and Balance controls in combination with proprietary interference rejection and singular shielding/grounding techniques achieve the highest level of musical accuracy.

  • Music reproduction to dream of

  • Featuring two true balanced inputs and three unbalanced inputs

  • 100-1000 times better interference rejection than other so-called "balanced" equipment.
    The result - total silence in between the music. 


  • Proprietary enhanced Class A circuitry

  • Tremendous headroom and reserves in input signal handling capability

  • Identical balanced input paths

  • Discrete Class A tape auxiliary send and return guarantees superior recordings and connection to auxiliary equipment.

  • Unparalleled freedom from noise & interference

  • Unique, true balanced outputs automatically optimize performance with balanced, pseudo-balanced or unbalanced loads

  • Outputs drive any load and long cables with perfect reproduction and stability

  • Fully discrete individually tuned circuitry built with special curve-tracer analysed and listening-selected semi-conductors

  • Precision "Balance" and "Output Level" controls guarantee freedom from noise & interference.

  • Internal transformer utilises a special dual shield that prevents stray fields.

  • Internal ultra low impedance power supply

  • Multiple on-board stabilisation and further stabilisation next to individual amplification stages

  • Hand-selected and individually matched components of DIN, IEC & MIL standards

  • Modular concept guarantees that the FM 255-MKII-R does not become obsolete

  • Superior in all aspect

  • The Resolution Series® 255 MK-II-R is THE ultimate precision line stage for use with true-balanced, pseudo-balanced and unbalanced sources

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