Grace Design proudly presents the model 901 reference headphone a

mplifier, designed to provide engineers and musicians with the finest

quality headphone amplification available for tracking, mixing and ma

stering. Born of the same inspiration and attention to detail as our aw

ard winning microphone preamplifiers, the model 901 is a truly uniqu

e tool designed to help studio professionals achieve better results an

d hear sonic detail like never before. The model 901 was designed w

ith difficult to drive, low impedance headphones in mind. With its hig

h current transimpedance output amplifier, the 901 is can control the t

ransducers in your headphones with dramatically better accuracy an

d resolution than the amplifiers in a typical console, tape recorder, C

D player or sound card. The 901 hosts analog and digital inputs whic

h make it convenient to monitor from several sources, and the ultra pr

ecise volume control ensures that you will hear your recordings with

perfect stereo balance at any monitor volume. Simply put, the model 9

01 is able to present a soundfield so well balanced and articulated, y

ou will discover new details and nuances in familiar tracks you have

never heard before. Now imagine how this will empower your ability t

o hear and manipulate subtle, yet critical elements in your work. GAI

N DISTORTION Normal Mode 10dB THD N Boost Mode 20dB 10dB

u out, 50 Ohm load 0.0051% FREQUENCY RESPONSE SMPTE 4:1 @ 0

dBu out /- .25dB 22Hz - 120kHz 10dBu out, 50 Ohm load <0.012%

@ 0dBu out /- .5dB 12Hz - 260kHz ATTENUATOR CHANNEL MATCHI

NG @ 0dBu out /-3dB 4Hz - 600kHz 24 position switch <0.05dB MAX

IMUM OUTPUT LEVEL D/A SPECIFICATIONS @1kHz, 50 Ohm load 2

3dBu (10.9Vrms) Input sample rate 32, 44.1, 48, 88.2, 96kHz IMPEDAN

CE THD N INPUT 40K Ohms balanced 44.1kHz, 24-bit, 1kHz, 20dBu

out 0.0016% 20K Ohms unbalanced NOISE FLOOR OUTPUT 1 Ohm 0d

B gain, 22-22kHz -95dBu DYNAMIC RANGE 0dB gain, A-weighted -1

02dBu @ 0dB gain 116dB POWER REQUIREMENTS @ -10dB gain 121

dB 115VAC .16A 100VAC/120VAC/220VAC/240VAC