Grace Design m103 Channel Strip – mic preamplfier Grace Design

The m103 starts with the tried and true m101 microphone preamplifier circuity. For many engineers, the m101 is an introduction to what quality mic preamplification is all about, and the perfect starting point for a channel strip – musical, transparent and pure. Headroom, detail, clarity – its all there. Complete with our exclusive ribbon mic mode, a 75Hz HPF and 48V phantom.

The 3 band EQ section is built around single stage parallel tuning architecture, which minimizes circuitry and delivers natural tonal shaping from 20Hz to 20kHz. Controls include a fully parametric mid, with sweepable high and low bands which can be operated in shelving or peak modes. Because of its accuracy of this design, smaller increments of cut or boost can be heard, providing a greater level of control over tone shaping.

The compressor circuit is based on an optical attenuator – the purest, high fidelity gain control mechanism available. It provides gentle limiting to fairly heavy compression, while remaining neutral and transparent. The perfect way to zip it all up and send it downstream – clean, intact and alive.

10 segment gain reduction and output meters make monitoring compression and output levels simple. The front panel accessed HI-Z input makes this an amazingly high quality instrument preamp. Comprehensive I/O options allow the mic pre and EQ/COMP sections to be accessed independently of each other, and the order of the EQ/COMP is switchable.

A dual function link/ sidechain input on rearpanel is provided for inserting external sidechain signals (for de-essing, ducking) or connecting two m103’s together for stereo compression applications. Predictably, the m103 is built to last, and proudly backed by our 5 year transferable warranty. So there it is, we’ve done it. The m103 – a channel strip by name, a powerful tool by design.

 

Features:

Fast and musical transimpedance microphone preamplifier architecture

Updated audio path with 0.5% precision metal film resistors

New 12 position gold plated rotary gain switch

High performance output line driver amplifier and HPF amplifier

Ribbon mic mode (also great for dynamic mics) -Relay bypass of phantom power decoupling capacitors, increased input impedance, and 48V lockout

3-band presicion EQ, fully parametric mid band, peak and shelf mode for hi and low bands

newly designed optical compressor

Mic amp direct output

EQ/COMP section line input

Bombproof laser-etched black anodized frontpanel

Sealed gold contact relay for Hi-Z input switching

Built in power supply

Led indicators for +48V, Ribbon mode, and HPF

powerful 10 segment meters for gain reduction and output level

Five year transferable warranty on parts and labor

Made in the USA

Specifications:

GAIN RANGE (5dB steps)
Mic input	10-65dB
Hi-Z input	-10-45dB
THD+N 1kHz, 22Hz-22kHz BW
@ 20dB Gain +20dBu out	<0.00085%
@ 40dB Gain +20dBu out	<0.0010%
@ 60dB Gain +20dBu out	<0.0050%
INTERMODULATION DISTORTION
@ 40dB Gain +20dBu out
SMPTE/DIN 4:1 7kHz/50Hz	<0.0020
NOISE – REFERRED TO INPUT @60dB Gain 22Hz-22kHz BW
50Ω source	<-130dB
150Ω source	<-128dB
600Ω source	<-124dB
CMRR @60dB Gain, 3.5Vcm
100Hz	>60dB
1kHz	>75dB
10kHz	>65dB
FREQUENCY RESPONSE
Mic input @ 40dBm Gain -3dB	3.7Hz-140kHz
Hi-Z input @ 20dB Gain -3dB	1.2Hz-112kHz
IMPEDANCE
Mic input	8.1kΩ
Mic input, Ribbon mode	20kΩ
Hi-Z input (unbalanced)	2.5MΩ
Hi-Z input (balanced)	5MΩ
Balanced Output	300Ω
Unbalanced Output	150Ω
PEAK LED METER
Green threshold	-10dBu
Red threshold	+16dBu
MAXIMUM OUTPUT LEVEL
100k Ohm load, 0.1% THD	+28dBu
EQ/COMP Section
GAIN RANGE
Output Trim	-10 – +10dB
EQ: 3 Bands of 0-12dB Cut or Boost
Low Frequency Range	20Hz – 750Hz
Mid Frequency Range	500Hz – 4kHz
Mid Frequency Q	0.5 – 5
High Frequency Range	3kHz – 20kHz
Low and High Frequency Peak/Shelf switches
Compressor – Inserts Pre or Post EQ
Threshold Range	-15 – +15 dBu
Attack Range	3 – 200 ms
Release Range	0.03 – 3 s
Ratio Range	1:1 – 12:1
Gain Reduction	0 – 10dB
THD+N 1kHz, 22Hz-22kHz BW
@ 0dB Gain +20dBu out	<0.002%
INTERMODULATION DISTORTION
@ 0dB Gain +20dBu out
SMPTE/DIN 4:1 7kHz/50Hz	<0.002%
OUTPUT NOISE 22Hz-22kHz BW
@0dB Gain	<-78dB
CMRR @0dB Gain, 3.5Vcm
100Hz	>75dB
1kHz	>75dB
10kHz	>75dB
FREQUENCY RESPONSE
@0dB Gain -3dB	0.016Hz-150kHz
IMPEDANCE
Line In	24kΩ
Main Out balanced	350Ω
Main Out unbalanced	150Ω
Link In – sidechain mode	100kΩ
LEVEL METERS
EQ Peak threshold	6 dB below interstage clipping
Output Level VU Meter	0dB VU = +4dBu output
Gain Reduction Meter	0-10dB Gain Reduction
MAXIMUM OUTPUT LEVEL
100k Ohm load, 0.1% THD	+28dBu
WEIGHT and DIMENSIONS
4.5 lbs	H1.7” x W19” x D9.0”
2.05 kg	H4.3cm x W48.3cm x D22.9cm
POWER CONSUMPTION
85-264VAC / 120-370VDC	14 Watts Max