khaos974
Headphoneus Supremus
- Joined
- Mar 19, 2008
- Posts
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From http://www.gracedesign.com/products/m903/m903.htm
It seems like a m902 update with better USB support, otherwise the specs are very close to the m902.
Price point: 1700/1800 $


Updated Specs from m903_manual_RevA.pdf
[size=9pt]SPECIFICATIONS ANALOG IN[/size]
[size=9pt]Gain – Balanced Input[/size]
[size=9pt]Headphone output, volume at maximum 0dB[/size]
[size=9pt]Balanced Line output, volume at maximum +4dB[/size]
[size=9pt]Unbalanced Line output, volume at maximum -8dB[/size]
[size=9pt]Frequency Response – Unbalanced In > Unbalanced Out[/size]
[size=9pt]@ 0dBu out +/- .25dB 27Hz – 54kHz[/size]
[size=9pt]@ 0dBu out +/- .5dB 18Hz – 80kHz[/size]
[size=9pt]@ 0dBu out +/-3dB 6.5Hz – 226kHz[/size]
[size=9pt]Maximum Input Level[/size]
[size=9pt]Balanced Input +22dBu[/size]
[size=9pt]Unbalanced Input +16dBu[/size]
[size=9pt]Maximum Output Level[/size]
[size=9pt]Unbalanced output @1kHz, 100k Ohm load +21.5dBu[/size]
[size=9pt]Balanced output @1kHz, 100k Ohm load +27dBu[/size]
[size=9pt]Headphone output @1kHz, 50 Ohm load +20dBu[/size]
[size=9pt]Impedance[/size]
[size=9pt]Balanced Input 106K Ohms[/size]
[size=9pt]Unbalanced Input 53K Ohms[/size]
[size=9pt]Balanced Output 95 Ohms[/size]
[size=9pt]Unbalanced Output 47.5 Ohms[/size]
[size=9pt]Headphone Output 1.2 Ohm[/size]
[size=9pt]Dynamic Range[/size]
[size=9pt]@ 0dB gain, Balanced In > Balanced Out 117dB[/size]
[size=9pt]@ 0dB gain, Balanced In > Headphone Out 116dB[/size]
[size=9pt]THD+N Balanced Input[/size]
[size=9pt]Headphone Out @ +10dBu, 50 Ohm load, SMPTE 4:1 <0.020%[/size]
[size=9pt]Headphone Out @ +10dBu, 50 Ohm load <0.0060%[/size]
[size=9pt]Unbalanced Line Out @ +10dBu, 100k Ohm load <0.00026%[/size]
[size=9pt]Balanced Line Out @ +20dBu, 100k Ohm load <0.00036%[/size]
[size=9pt]Attenuator[/size]
[size=9pt]Channel matching <0.05dB[/size]
[size=9pt]Attenuator Range 97.5dB[/size]
[size=9pt]Output Noise Floor, Balanced Input[/size]
[size=9pt]Balanced Output, volume at maximum, 22-22kHz -90dBu[/size]
[size=9pt]Balanced Output, volume at minimum, 22-22kHz -103dBu[/size]
[size=9pt]Unbalanced Output, volume at maximum, 22-22kHz -101dBu[/size]
[size=9pt]Unbalanced Output, volume at maximum, 22-22kHz -105dBu[/size]
[size=9pt]SPECIFICATIONS D/A CONVERTER[/size]
[size=9pt]Input Sample Rate 32, 44.1, 48, 88.2, 96, 176.4, 192kHz[/size]
[size=9pt]THD+N[/size]
[size=9pt]44.1kHz, 24bit, 1kHz, -1dBFS, Unbalanced Out @ +15dBu <0.0009%[/size]
[size=9pt]44.1kHz, 24bit, 1kHz, -1dBFS, Balanced Out @ +15dBu <0.0006%[/size]
[size=9pt]Output level[/size]
[size=9pt]Unbalanced Output @ 0dBFS, Volume at maximum, trim at 0 +9dBu[/size]
[size=9pt]Blanced Output @ 0dBFS, Volume at maximum, trim at 0 +21dBu[/size]
[size=9pt]Power Requirements[/size]
[size=9pt]120VAC 0.16A[/size]
[size=9pt]230VAC 0.08A[/size]
[size=9pt]DIMENSIONS AND WEIGHT[/size]
[size=9pt]Dimensions H1.7” x W8.5” x D8.25”[/size]
[size=9pt]Weight 5 lbs (2.2kg)[/size]
It seems like a m902 update with better USB support, otherwise the specs are very close to the m902.
Price point: 1700/1800 $
- Balanced and unbalanced analog inputs
- 24bit/192kHz digital stereo inputs- AES3, S/PDIF, TOSLINK and USB
- High speed USB interface - completely asynchronous transfer mode allows for bit-perfect playback with zero interface induced jitter
- Driverless operation on Windows & Mac up to 96kHz/24bit
- Supports USB Class 2 audio specification for 192kHz/24bit operation on Windows & Mac (drivers needed for 192kHz operation under Windows)
- New generation DAC's and ultra low noise balanced current to voltage converter yields more musical performance compared to the m902
- Mono mode for checking mix phase issues (or listening to Pet Sounds)
- s-Lock™ phase lock loop sample clock regeneration for ultra-low jitter and rock solid digital stability
- High-current transimpedance headphone amplifier circuitry built to effortlessly drive low impedance headphones
- Balanced and unbalanced variable level analog line outputs
- Improved power supply architecture isolates headphone power amplifiers, line amplifiers, DAC's and digital logic
- Precision level control with a 99.5dB range in 0.5 dB steps
- Channel level matching accuracy of 0.05dB
- Improved x-feed circuit eliminates perceived loss of low frequency content
- Optional infrared remote control available
- Internal linear power supply with custom wound toroidal transformer
- Sealed gold contact relays used for all signal switching
- Five year transferable warranty on parts and labor
Updated Specs from m903_manual_RevA.pdf
[size=9pt]SPECIFICATIONS ANALOG IN[/size]
[size=9pt]Gain – Balanced Input[/size]
[size=9pt]Headphone output, volume at maximum 0dB[/size]
[size=9pt]Balanced Line output, volume at maximum +4dB[/size]
[size=9pt]Unbalanced Line output, volume at maximum -8dB[/size]
[size=9pt]Frequency Response – Unbalanced In > Unbalanced Out[/size]
[size=9pt]@ 0dBu out +/- .25dB 27Hz – 54kHz[/size]
[size=9pt]@ 0dBu out +/- .5dB 18Hz – 80kHz[/size]
[size=9pt]@ 0dBu out +/-3dB 6.5Hz – 226kHz[/size]
[size=9pt]Maximum Input Level[/size]
[size=9pt]Balanced Input +22dBu[/size]
[size=9pt]Unbalanced Input +16dBu[/size]
[size=9pt]Maximum Output Level[/size]
[size=9pt]Unbalanced output @1kHz, 100k Ohm load +21.5dBu[/size]
[size=9pt]Balanced output @1kHz, 100k Ohm load +27dBu[/size]
[size=9pt]Headphone output @1kHz, 50 Ohm load +20dBu[/size]
[size=9pt]Impedance[/size]
[size=9pt]Balanced Input 106K Ohms[/size]
[size=9pt]Unbalanced Input 53K Ohms[/size]
[size=9pt]Balanced Output 95 Ohms[/size]
[size=9pt]Unbalanced Output 47.5 Ohms[/size]
[size=9pt]Headphone Output 1.2 Ohm[/size]
[size=9pt]Dynamic Range[/size]
[size=9pt]@ 0dB gain, Balanced In > Balanced Out 117dB[/size]
[size=9pt]@ 0dB gain, Balanced In > Headphone Out 116dB[/size]
[size=9pt]THD+N Balanced Input[/size]
[size=9pt]Headphone Out @ +10dBu, 50 Ohm load, SMPTE 4:1 <0.020%[/size]
[size=9pt]Headphone Out @ +10dBu, 50 Ohm load <0.0060%[/size]
[size=9pt]Unbalanced Line Out @ +10dBu, 100k Ohm load <0.00026%[/size]
[size=9pt]Balanced Line Out @ +20dBu, 100k Ohm load <0.00036%[/size]
[size=9pt]Attenuator[/size]
[size=9pt]Channel matching <0.05dB[/size]
[size=9pt]Attenuator Range 97.5dB[/size]
[size=9pt]Output Noise Floor, Balanced Input[/size]
[size=9pt]Balanced Output, volume at maximum, 22-22kHz -90dBu[/size]
[size=9pt]Balanced Output, volume at minimum, 22-22kHz -103dBu[/size]
[size=9pt]Unbalanced Output, volume at maximum, 22-22kHz -101dBu[/size]
[size=9pt]Unbalanced Output, volume at maximum, 22-22kHz -105dBu[/size]
[size=9pt]SPECIFICATIONS D/A CONVERTER[/size]
[size=9pt]Input Sample Rate 32, 44.1, 48, 88.2, 96, 176.4, 192kHz[/size]
[size=9pt]THD+N[/size]
[size=9pt]44.1kHz, 24bit, 1kHz, -1dBFS, Unbalanced Out @ +15dBu <0.0009%[/size]
[size=9pt]44.1kHz, 24bit, 1kHz, -1dBFS, Balanced Out @ +15dBu <0.0006%[/size]
[size=9pt]Output level[/size]
[size=9pt]Unbalanced Output @ 0dBFS, Volume at maximum, trim at 0 +9dBu[/size]
[size=9pt]Blanced Output @ 0dBFS, Volume at maximum, trim at 0 +21dBu[/size]
[size=9pt]Power Requirements[/size]
[size=9pt]120VAC 0.16A[/size]
[size=9pt]230VAC 0.08A[/size]
[size=9pt]DIMENSIONS AND WEIGHT[/size]
[size=9pt]Dimensions H1.7” x W8.5” x D8.25”[/size]
[size=9pt]Weight 5 lbs (2.2kg)[/size]