Ferrum OOR Headphone Amplifier Front - Douglas HiFi Perth
Ferrum OOR Headphone Amplifier Rear - Douglas HiFi Perth
Ferrum OOR Headphone Amplifier with optional Hypsos Power Supply - Douglas HiFi Perth

Ferrum OOR Balanced Headphone Amplifier

Regular price $2,999.00
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Ferrum OOR Balanced Headphone Amplifier

With the world of Headphone listening growing in popularity and even spawning it's own category - HeadFi... there is an increased need for high quality specialised headphone amplifiers. The Ferrum OOR is a true balanced fully discrete analogue headphone amplifier with selectable gain settings and both single ended and balanced inputs and outputs. The Ferrum OOR also has the ability to upgrade the sound quality utilising the award winning Ferrum Hypsos power supply as an optional add on.

OOR, the only headphone amplifier with a soul

OOR will redefine the category of headphone amplifiers. OOR will drive any headphones effortlessly to the max of their potential, while preserving the essence of the music it amplifies. Ultra low distortion, zero fatigue, huge dynamics and unrivaled detail result in ultimate enjoyment. OOR actually makes something that is very difficult to accomplish, seem like the most natural thing on earth. The most important features are:


Truly Balanced

The signal path stays truly balanced using the XLR inputs and becomes truly balanced using the RCA inputs.


Ease of use

only three knobs on the front panel to control the most important settings.


Ferrum Power Link

OOR performs very, very good right out of the box. But OOR is made to excel above and beyond when used together with HYPSOS. We use what we dubbed our Ferrum Power Link (FPL in short) to connect the two. HYPSOS then will perform to its maximum, unleashing unheard musicality from the combination with OOR.


Superior control

perfected steering of output transistors protect them and never let them turn off, therefore reducing distortion to inaudible levels and keeping them in a state where they can instantly unleash all their power, crucial for high dynamics, superlative control and authority in sound.


Enhanced transparency

The whole design is focussed on a balanced and very transparent sound signature, making listening fatigue something of the past.


Discrete design

The discrete power amp technology is developed in-house to achieve the best possible analog quality.

Ferrum OOR Headphone Amp Specifications

  • Gain (dB): balanced -4 dB, + 6dB, +16 dB / single ended -10 dB, 0 dB, 10 dB
  • Operation: Fully balanced, proprietary discrete power amp technology
  • Inputs: XLR, RCA, 2.5 mm DC connector centre positive, proprietary 4-pin DC connector
  • Outputs: Balanced 4-pin XLR, 6.35 mm jack
  • Frequency Response:  20 Hz – 100 kHz 0.1 dB
  • Output Power Single Ended: 400 mW into 300 Ω, 2 W into 60 Ω
  • Output Power Balanced: 1.600 mW into 300 Ω, 8 W into 60 Ω
  • THD + Noise: TBA
  • Input Impedance: 94 kΩ
  • Output Impedance Single Ended: 22 Ω on pre-amp
  • Output Impedance Balanced: 44 Ω on pre-amp
  • Output headphones Impedance: < 0.3 Ω
  • Power Consumption: Idle <15 W
  • Power Adapter: 100/240 V AC to 22-30 V DC
  • Dimension (W x D x H) (In/cm): 8.6 x 8.1 x 2.0 inch / 21.7 x 20.6 x 5 cm
  • Weight (kg/lbs): 1.8 kg / 3.97 LBS