While 5.1 surround has become well established in film and HD production, stereo is still king and remains the standard for producing and delivering music. Accordingly, we offer our monitor controller in stereo only versions - the m904 (and m904b).
The m904 combines all the same features and technology found in our flagship m906 surround controller, and is the perfect nerve center for any type of audio production facility - from project studio to world class mastering facility.
The m904 offers a full complement of balanced and unbalanced stereo analog and digital inputs, the latter featuring our latest generation reference 24bit/192kHz DAC technology with our proprietary s-Lock¢â PLL for rock solid digital stability (more info can be found in the technical discussion). All inputs and outputs are easily user calibrated for seamless integration into any playback environment with all types of playback equipment.
The m904 is configured as a 2U rack chassis, with all system controls built into the front panel, or is available as the m904b, with a blank 2U mainframe which is controlled by a separate remote control unit (m904RCU sold separately). Additionally, a standard m904 can be used with the m904RCU, so the user can select between local and remote control.
Included as a standard feature is our critically acclaimed reference headphone amplifier circuitry (as featured in our m902), with two output jacks on the mainframe or one jack on the m904b and one on the m904RCU. This circuitry provides absolutely pristine audiophile headphone amplification for critical monitoring, mixing and mastering.
While the m904 provides an unparalleled list of useful features, the real achievement for us was to implement all of this while maintaining our trademark musical, high fidelity audio performance. All components are selected and design decisions made for absolute audio transparency and long term reliability, making this the perfect link between your mix and monitors.
The m904 is here to empower audio professionals with the highest performance and most comprehensive feature set that any stereo monitor control system has to offer.
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- multiple stereo analog inputs
- 24bit/192kHz digital stereo inputs- AES3, S/PDIF, ADAT and TOSLINK
- s-LockTM phase lock loop sample clock regeneration for ultra-low jitter and rock solid digital stability
- precision speaker and headphone level controls with a 100dB range in 0.5dB steps
- every electrical and mechanical design element maximized for absolute purist, audiophile performance
- available as the m904b, which has a blank panel mainframe unit and is controlled via m904RCU (sold separately)
- all I/O and audio are routed in the 2U rack mount mainframe powered by an internal AC supply
- multiple speaker set selection - up to 3 stereo sets
- m902 style high-current audiophile headphone amplifier built in with two outputs on front panel
- complete system level calibration (inputs, outputs, inter-channel balance, dim)
- balanced talkback microphone input and activation switch with additional external foot switch control jack
- fixed level stereo DAC output for direct audio transfers
- five year warranty on parts and labor
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ANALOG INPUT |
THD+N @ 0dB gain, 1kHz |
|
+20dBu out |
<0.001% (0.00075% typical) |
+10dBu out |
<0.003% (0.001% typical) |
0dBu out |
<0.009% (0.005% typical) |
Intermodulation Distortion SMTPE/DIN 4:1 50Hz, 7kHz |
@+20dBu out |
<0.002% (0.0015% typical) |
@ 0dBu out |
<0.008% (0.006% typical) |
Frequency Response |
+/-3dB |
3Hz - 250Khz |
Dynamic Range |
20-22kHz bandwidth |
112dB |
20-22kHz bandwidth and A weighting filter |
115dB |
Output Noise |
20-22kHz bandwidth, -20dB gain |
|
High gain mode |
-89dBu |
Low gain mode |
-98dBu |
20-22kHz bandwidth and A weighting filter, -20dB gain |
|
High gain mode |
-91dBu |
Low gain mode |
-99dBu |
Phase Deviation |
20Hz to 20kHz |
< 4 |
10Hz to 100kHz |
< 15 |
Crosstalk any channel |
100Hz |
< 100dB |
1kHz |
< 100dB |
20kHz |
< 85dB |
Balanced Input CMRR |
60Hz |
> 65dB |
1kHz |
>65dB |
10kHz |
>60dB |
Gain Range |
Low gain mode (0.5dB steps) |
-105.5dB to +20dB |
High gain mode (0.5dB steps) |
-95.5dB to +30dB |
Channel Tracking Accuracy |
Any channel |
+/-0.05dB |
Maximum Output Level |
Low gain mode (balanced) |
+15dBu |
High gain mode (balanced) |
+27dBu |
Maximum Input Level |
Balanced inputs |
+30dBu |
Unbalanced inputs |
+20dBu |
Impedances |
Balanced inputs |
30k Ohms |
Unbalanced inputs |
50k Ohms |
Balanced outputs |
300 Ohms |
Minimum load impedance |
300 Ohms |
DIGITAL TO ANALOG CONVERTER FIXED OUTPUTS |
Output Levels |
User selectable (0dBFS) |
+16dBu / +24dBu |
Fixed output trim range (0.5dB steps) |
-95.5dB to +30dB |
THD+N |
1kHz, -1dBFS, 20-22kHz bandwidth (44.1kHz) |
0.00% |
Dynamic Range |
20-22kHz bandwidth |
>111dB |
Input Lock Range |
AES3/SPDIF |
32kHz to 192kHz |
TOSLINK |
32kHz to 96kHz |
ADAT LIGHTPIPE |
30kHz 55kHz |
S-Lock Sample Clock Intrinsic Jitter |
20-22kHz bandwidth |
<25ps |
s-Lock¢â Sample Clock Jitter Rejection |
1kHz sine jitter |
-40dB |
S-Lock Supported Sample Rates |
AES3, SPDIF |
44.1, 48, 88.2, 96, 176.4, 192kHz |
TOSLINK |
44.1, 48, 88.2, 96kHz |
ADAT LIGHTPIPE |
44.1, 48kHz |
S-Lock Capture Range |
44.1, 48kHz |
+/- 10Hz |
88.2, 96kHz |
+/- 20Hz |
176.4, 192kHz |
+/- 40Hz |
Word Clock / Superclock Input |
Impedance (switchable) |
75 Ohms / 1M Ohms |
Minimum Voltage |
3V peak to peak |
Maximum Voltage |
5V peak to peak |
Word clock frequencies supported |
44.1, 48, 88.2, 96, 176.4, 192kHz |
Superclock frequencies supported |
11.2896MHz, 12.288MHz (256x fs) |
POWER SUPPLY / MECHANICAL SPECS |
Power consumption |
30W |
Input Voltage 50-60Hz |
100, 120, 220, 230-240VAC |
Dimensions |
Main chassis IEC 2U |
3.5" x 10.5" x 17" |
Remot control unit |
1.6" x 8" x 5.25" |
Weight |
Main chassis |
14.1lbs / 6.4kg |
Remote control unit |
2.3lbs / 1kg |
All specifications are subject to change without notice |
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