m908 User Manual, Rev. G
Setup as HD I/O #2 and receive audio from Pro|Tools on the first 16 channels of the m908
Digilink interface.
7.4 Phono Preamp Option Module
The m908 phono module is a high performance RIAA preamplifier. This option is available on
new and existing units. Please contact your Grace Design dealer or distributor for details.
The phono amplifier can be optimized for a wide range of phono cartridges via a number of
internal jumper settings. Moving magnet cartridges can be accommodated with the 40dB gain
setting and 47k Ω input impedance. Low output moving coil cartridges can be accommodated
with the 60dB gain setting and 100 Ω input impedance. The phono module also provides variable
input loading from 0-500 Ω with VR1 and VR2. Connect an Ohm meter to the unbalanced input
jacks to set the input loading to the cartridge recommended setting.
To access these jumpers, remove the top cover of the m908 and refer to the Jumper Location
diagram below. Be sure to unplug the AC power cord before removing the m908 top cover.
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