Ønsker man det absolutte reference instrument i produktion af musik eller bare en audiophil schweizerkniv får man det i m903 hovedtelefonforstærkeren fra Grace Design.

Reference-hovedtelefonforstærkeren m903 byder på en lang række inputs – balancerede/ubalancerede analoge og digitale (inklusiv USB), ligesom den er udstyret med et ”Natural Crossfeed Filter”, der gør den i stand til at simulere forskellige akustiske miljøer (HRTF – Head Related Transfer Functions). 

Grace Design om m903:

Professionals and audiophiles alike will be simply floored by the m903’s latest generation, high performance 24/192 DAC, which includes our unique s-LockTM dual stage PLL (Phase Lock Loop) for extremely low intrinsic jitter and rock solid digital performance. A full complement of analog and digital inputs are available (AES3, S/PDIF, TOSLINK and USB), which are all selectable via a front panel rotary switch.

The core of the m903 is a meticulously designed high-current transimpedance amplifier circuitry, which is designed to effortlessly drive even the lowest impedance headphones and provide the high-resolution and low-level ambient detail. Familiar recorded material becomes at once transparent and alive, and critical details in editing and mastering become obvious and easy to manipulate.

The m903 includes a crossfeed circuit, or XFeed, which simulates the natural acoustics of a loudspeaker listening environment and HRTF (Head Related Transfer Functions). 

The m903 also cleverly adds stereo unbalanced analog line outputs for connection to studio monitors or any speaker system, allowing it to double as an elegantly simple high fidelity monitor controller or even a purist audiophile preamplifier / DAC.

Specifikationer:
• Headphone amplifier with digital and analog inputs. 
• Input sample rates: 32–192kHz. 
• Maximum voltage gain: 0dB (Normal), 10dB (Boost). 
• Frequency response at 0dBu output: 4Hz–600kHz, ±3dB. 
• Maximum output level: 21.4dBu (9.11V RMS). 
• Input impedance: 106k ohms balanced, 53k ohms, unbalanced. 
• Output impedance: 1 ohm. 
• THD+N: <0.08% at 10dBu into 50 ohms, headphone output; <0.002%, at 10dBu into 50 ohms, line output. 
• IMD (SMPTE 4:1): <0.08% at 10dBu into 50 ohms.

Dimensions: B: 21,59 cm D: 20,95 cm H: 4,45 cm. Vægt: 2.2kg.

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