Grace Design m906 5.1 Monitor System w/ Downmix Option
Grace Design's m906 High Fidelity 5.1 Monitor System is a premium surround monitor control system with intelligent ergonomics to match it's superior fidelity and purity of design. This m906 comes with the DOWNMIX Option module factory installed. The DOWNMIX creates a stereo L+R mix of a 6 channel surround source. All standard Dolby mix ratios can be calibrated by the user for both the center and surround channels.
The Grace Design m906 High Fidelity 5.1 Monitor System satisfies the more and more vital need for a high quality studio monitor controller, while the computer increasingly becomes the de-facto tool for audio production, and the need for the traditional large format console becomes muted.
The original concept for building the m906 was simply to provide a high fidelity level control for engineers working with 5.1 surround playback systems. From there, however, Grace Design became blissfully carried away and ultimately obsessed with creating the most full featured and highest quality monitor controller available.
So at its core, the m906 is a purist level control for monitoring surround audio sources. But a closer look reveals a totally comprehensive feature set that makes this system the essential nerve center for any large recording facility centered around a high-definition digital audio workstation.
The m906 offers a full compliment of balanced and unbalanced analog 5.1 and digital 5.1 and stereo inputs - the latter featuring Grace Design's latest generation reference quality 24/192 DAC technology. All inputs and outputs can be user calibrated for seamless integration into any playback environment with all types of playback equipment.
The m906 is configured as a 2U rack mount mainframe controlled by a sleek, convenient desktop control. All audio is kept in the mainframe and all control is via the remote control.
Also included as a standard feature is our critically acclaimed m902 headphone amplifier circuitry, with one output jack on the mainframe and one additional output on the remote. This circuitry provides true audiophile headphone amplification for critical monitoring, mixing and quality control.
While the m906 boasts a remarkable compliment of useful features, the real achievement for Grace Design is to provide all of this while maintaining the impeccable, transparent audio performance for which all of their products are famous. The m906 is designed to empower audio professionals with the highest performance and most comprehensive feature set that any monitor control system has to offer.
Grace Design's DA and AD converters employ their proprietary s-Lock circuit, a two stage PLL (phase lock loop) system to provide practically jitter-free recovered clocks with extremely high incoming jitter attenuation. The first stage is a wide lock range ultra low noise analog PLL, which can lock to incoming word clocks and Avid/Digidesign Loop Sync signals with a +/-8% lock range. Rather than using standard CMOS based PLL chips for the first stage PLL, Grace Design uses an extremely quiet, discrete VCO (voltage controlled oscillator). When using a quality external clock source, this PLL alone will provide a nearly crystal quality clock. The incoming jitter rejection of this PLL begins at 500Hz and increases at 12dB/octave with rising frequency. The wide lock range allows for the converter to actually operate in vari-speed applications without a sacrifice in audio performance, provided that the external clock source is relatively low jitter.
When the incoming sample rate is within +/-200 ppm of the selected sample rate, the secondary (our proprietary s-Lock) crystal based PLL will lock to the first stage PLL, providing the quietest possible recovered sample clock to the converters. The s-Lock PLL is capable of extreme rejection of incoming jitter, which begins at less than 0.1Hz and is better than 60dB at 1kHz.
While it is very easy (and economical) to provide "jitter free" sample clocks by routing the audio data through an ASRC (asynchronous sample rate converter), Grace Design believes that the convenience of these circuits does not outweigh the potential sonic degradation caused by additional signal processing. The performance of the s-Lock PLL renders even the worst case interface jitter artifacts to a level well below the noise floor of the converter.
The Downmix Option
This m906 can be equipped with an optional DOWNMIX module that creates a stereo L+R mix of a 6 channel surround source. All standard Dolby mix ratios can be calibrated by the user for both the center and surround channels. If installed, operation is as followes:
To toggle the DOWNMIX mode, press and hold the MUTE/SOLO button. Once enabled, the top line of the System LCD will display “DOWNMIX ACTIVE” (the display will toggle between this and the current input setup). Press and hold the MUTE/SOLO button again to exit DOWNMIX mode.
Once DOWNMIX is enabled, the composite stereo mix is routed to the corresponding Left and Right Control Room Outputs and the surround outputs are muted. Additionally, the downmixed signal is present as the Headphone Left and Right source and the MON->CUE source. The DOWNMIX ratios are variable and adjusted in CAL mode. The factory default settings are as follows:
CENTER Channel DOWNMIX Ratio = -3.0dB
LEFT and RIGHT Surround channel DOWNMIX ratio = -6.0dB
To Adjust the DOWNMIX Ratios:
- Enter CAL mode by pressing the CAL switch. The switch LED will begin to flash, indicating that you’re now in calibration mode.
- Press the MUTE/SOLO switch. The switch LED will begin to flash.
- DOWNMIX will be engaged and the LCD will display “DOWNMIX RATIO – CENTER LEVEL”.
- “CAL” will be displayed in the headphone level LED display while the current ratio is shown in the main level LED display.
- Rotate the ‘main level/edit’ rotary encoder in a counter-clockwise direction to increase the amount of attenuation. Rotate the encoder in a clockwise motion to decrease the value. Available ratios are --- (mute), -6.0dB, -4.5dB, -3.0dB, -1.5dB, 0.0dB, 1.5dB and 3.0dB.
- Press the MUTE/SOLO button again to access the DOWNMIX ratio for the LS and RS surround channels. The LCD will display “DOWNMIX RATIO – LS AND RS LEVEL”.
- Once you’re satisfied with the new DOWNMIX ratios, you can select a new function to edit or exit. Exit CAL mode and return to the normal operating state by pressing the flashing CAL switch.
MUTE/SOLO Functionality with DOWNMIX:
When DOWNMIX mode is enabled, the SOLO/MUTE buttons function in an alternate fashion. This functionality is very useful for quickly referencing each surround channel’s contribution to a downmix.
When DOWNMIX is enabled the LEFT, RIGHT and SUB MUTE/SOLO buttons are disabled and the LEFT and RIGHT channels are always ON. The SUB channel is always OFF.
The CENTER, LS and RS MUTE/SOLO buttons function as follows:
When SOLO mode is active, soloing a channel will cause non-soloed channels to be muted (not added to the downmix).
When MUTE mode is active, muting a channel removes it from the downmix.
Grace Design m906 5.1 Monitor System w/ Downmix Option
- Multiple 5.1 and stereo analog inputs
- 24bit/192kHz digital 5.1 and stereo inputs- AES3, S/PDIF, ADAT and TOSLINK
- s-Lock 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
- All controls are built into an elegant, convenient desktop remote control unit
- All I/O and audio are routed in a 2U rack mount mainframe powered by an external 1U 1/2 rack power supply
- Control up to three speaker systems - two 5.1 or up to three stereo
- m902 style high-current audiophile headphone amplifier built in with one output on remote control unit and one on the mainframe unit
- Complete system level calibration (inputs, outputs, inter-channel balance, dim) and individual channel solo/mute
- Balanced talkback microphone input and activation switch with additional external foot switch control jack
- Fixed level 5.1 DAC output for direct audio transfers
- Optional downmix module supports all standard Dolby mix ratios
- Optional AES Loop-thru feature provides four AES digital outputs for passing signals to other devices downstream
- FIVE YEAR transferable warranty on parts and labor
- The digital AES Loop-Thru Option outputs are derived as follows:
- L+R (AES5): This output provides the LEFT and RIGHT channels of the selected digital input.
- LR+RR (AES6): This output provides the LEFT REAR and RIGHT REAR channels of the 5.1 AES input when this input is selected.
- C+LFE (AES7): This output provides the CENTER and LOW FREQ channels of the 5.1 AES input when this input is selected.
- 2CH2 (AES8): This output provides the signal present on the 2CH2 AES input regardless of input selection.
- NOTE: The digital loop-thru outputs do not function for ADAT sources.
Grace Design m906 5.1 Monitor System w/ Downmix Option Specifications
- GENERAL ANALOG SPECIFICATIONS
- 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
- 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
- Maximum Output Level
- Low gain mode (balanced) +15dBu
- High gain mode (balanced) +27dBu
- Maximum Input Level
- Balanced inputs +30dBu
- Unbalanced inputs +20dBu
- 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
- 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
- S-Lock Sample Clock Jitter Rejection
- 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 60W
- Input Voltage 50-60Hz 100, 120, 220, 230-240VAC
- Main chassis IEC 2U 3.5" x 10.5" x 17"
- Remote control unit 1.6" x 8" x 5.25"
- Power supply unit 1.7" x 8.5" x 8.5"
- Main chassis 14.1lbs / 6.4kg
- Remote control unit 2.3lbs / 1kg
- Power supply unit 6.5lbs / 2.9kg
Grace Design m906 5.1 Monitor System w/ Downmix Option Includes
- m906 2 RU Mainframe
- m906 Remote
- m906 Remote Cable
- Power Supply w/ DC Power Cable
- IEC Power Cable
Grace Design m906 5.1 Monitor System w/ Downmix Option Downloads
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