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Mackie HM-400 Rack-Mountable, 4-Channel Headphone Amplifier

Key Features

XLR & 1/4" Stereo Inputs and Outputs
Three Headphone Outputs per Channel
Per-Channel 1/4" Stereo Aux Input
2-Band EQ, Balance, and Output Controls
L/R Mute Switches
Stereo/Mono Mode Switches
LED Metering
Includes Power Cable

Overview

The Mackie HM-400 is a rack-mountable, 4-channel headphone amplifier designed to provide versatile headphone amplification for artists, musicians, and engineers monitoring through headphones in live stage applications and home, project, commercial, and mobile-recording studios. It features a stereo main output via XLR and 1/4" jacks and twelve 1/4" TRS stereo headphone outputs—three per channel—fed by a customizable blend of inputs.

One stereo main input via XLR and 1/4" jacks can be mixed with a per-channel 1/4" stereo aux input. Each channel offers 2-band EQ for quick tone shaping, stereo balance or main/aux input mix control, and output level adjustments. Also on each channel are switches for muting left and/or right signals and operating in stereo or mono. 7-segment LED meters display main input and per-channel output levels.

Key Specs

Number of Headphone Channels	4-Channel
Headphone Output Power	550 mW per Side into 47 Ohms (Max)
Analog Audio I/O	2x XLR 3-Pin Balanced Input (1 Stereo Pair) 2x 1/4" TRS Balanced/Unbalanced Input (1 Stereo Pair) 1x 1/4" TRS Unbalanced Stereo Input 4x 1/4" TRS Unbalanced Stereo Aux Input 2x XLR 3-Pin Balanced Output (1 Stereo Pair) 2x 1/4" TRS Balanced Output (1 Stereo Pair) 12x 1/4" TRS Unbalanced Headphone Output
Power Requirements	AC Input

Number of Headphone Channels	4-Channel
Headphone Output Power	550 mW per Side into 47 Ohms (Max)
EQ	2-Band EQ per Channel
Display	5x Multi-Segment LED Meter

Connectivity

Analog Audio I/O

2x XLR 3-Pin Balanced Input (1 Stereo Pair)
2x 1/4" TRS Balanced/Unbalanced Input (1 Stereo Pair)
1x 1/4" TRS Unbalanced Stereo Input
4x 1/4" TRS Unbalanced Stereo Aux Input
2x XLR 3-Pin Balanced Output (1 Stereo Pair)
2x 1/4" TRS Balanced Output (1 Stereo Pair)
12x 1/4" TRS Unbalanced Headphone Output

Performance

Frequency Response	20 Hz to 20 kHz ±1 dB
Gain/Trim Range	Inputs: -66 to +18 dBu
Maximum Input Level	Line Inputs: +15 dBu Aux Inputs: +20 dBu
Maximum Output Level	Headphone Outputs: +21 dBu
Impedance	Inputs: 20 Kilohms (Balanced) 10 Kilohms (Unbalanced) Aux Inputs: 10 Kilohms (Unbalanced) Headphone Outputs: 3 Ohms (Unbalanced)
THD	< 0.01% (at +4 dBu, 1 kHz, Unity Gain)
Noise	-66 dB
CMRR	Line Inputs: > 42 dB (1 kHz)

Power

Power Requirements	AC Input
AC Input Power	100 to 120 VAC, 50 / 60 Hz 220 to 240 VAC, 50 / 60 Hz
Power Consumption	24 W

Physical

Rackmount Size	1 RU
Dimensions	19 x 8.8 x 1.8" / 483 x 224 x 46 mm
Weight	8.0 lb / 3.6 kg

Packaging Info

Package Weight	9.75 lb
Box Dimensions (LxWxH)	20.8 x 10.6 x 4.1"

What's in the Box:

Mackie HM-400 Rack-Mountable, 4-Channel Headphone Amplifier
Power Cable
Limited 1-Year Manufacturer Warranty

Product Information

Shipping & Returns

Mackie HM-400 Rack-Mountable, 4-Channel Headphone Amplifier

Key Features

XLR & 1/4" Stereo Inputs and Outputs
Three Headphone Outputs per Channel
Per-Channel 1/4" Stereo Aux Input
2-Band EQ, Balance, and Output Controls
L/R Mute Switches
Stereo/Mono Mode Switches
LED Metering
Includes Power Cable

Overview

Key Specs

Number of Headphone Channels	4-Channel
Headphone Output Power	550 mW per Side into 47 Ohms (Max)
Analog Audio I/O	2x XLR 3-Pin Balanced Input (1 Stereo Pair) 2x 1/4" TRS Balanced/Unbalanced Input (1 Stereo Pair) 1x 1/4" TRS Unbalanced Stereo Input 4x 1/4" TRS Unbalanced Stereo Aux Input 2x XLR 3-Pin Balanced Output (1 Stereo Pair) 2x 1/4" TRS Balanced Output (1 Stereo Pair) 12x 1/4" TRS Unbalanced Headphone Output
Power Requirements	AC Input

Number of Headphone Channels	4-Channel
Headphone Output Power	550 mW per Side into 47 Ohms (Max)
EQ	2-Band EQ per Channel
Display	5x Multi-Segment LED Meter

Connectivity

Analog Audio I/O

Performance

Frequency Response	20 Hz to 20 kHz ±1 dB
Gain/Trim Range	Inputs: -66 to +18 dBu
Maximum Input Level	Line Inputs: +15 dBu Aux Inputs: +20 dBu
Maximum Output Level	Headphone Outputs: +21 dBu
Impedance	Inputs: 20 Kilohms (Balanced) 10 Kilohms (Unbalanced) Aux Inputs: 10 Kilohms (Unbalanced) Headphone Outputs: 3 Ohms (Unbalanced)
THD	< 0.01% (at +4 dBu, 1 kHz, Unity Gain)
Noise	-66 dB
CMRR	Line Inputs: > 42 dB (1 kHz)

Power

Power Requirements	AC Input
AC Input Power	100 to 120 VAC, 50 / 60 Hz 220 to 240 VAC, 50 / 60 Hz
Power Consumption	24 W

Physical

Rackmount Size	1 RU
Dimensions	19 x 8.8 x 1.8" / 483 x 224 x 46 mm
Weight	8.0 lb / 3.6 kg

Packaging Info

Package Weight	9.75 lb
Box Dimensions (LxWxH)	20.8 x 10.6 x 4.1"

What's in the Box:

Mackie HM-400 Rack-Mountable, 4-Channel Headphone Amplifier
Power Cable
Limited 1-Year Manufacturer Warranty

$258.41

Mackie HM-400 Rack-Mountable, 4-Channel Headphone Amplifier—

$258.41

Mackie HM-400 Rack-Mountable, 4-Channel Headphone Amplifier—

$258.41

Product Information

Shipping & Returns

Description

Key Features

XLR & 1/4" Stereo Inputs and Outputs
Three Headphone Outputs per Channel
Per-Channel 1/4" Stereo Aux Input
2-Band EQ, Balance, and Output Controls
L/R Mute Switches
Stereo/Mono Mode Switches
LED Metering
Includes Power Cable

Overview

Key Specs

Number of Headphone Channels	4-Channel
Headphone Output Power	550 mW per Side into 47 Ohms (Max)
Analog Audio I/O	2x XLR 3-Pin Balanced Input (1 Stereo Pair) 2x 1/4" TRS Balanced/Unbalanced Input (1 Stereo Pair) 1x 1/4" TRS Unbalanced Stereo Input 4x 1/4" TRS Unbalanced Stereo Aux Input 2x XLR 3-Pin Balanced Output (1 Stereo Pair) 2x 1/4" TRS Balanced Output (1 Stereo Pair) 12x 1/4" TRS Unbalanced Headphone Output
Power Requirements	AC Input

Number of Headphone Channels	4-Channel
Headphone Output Power	550 mW per Side into 47 Ohms (Max)
EQ	2-Band EQ per Channel
Display	5x Multi-Segment LED Meter

Connectivity

Analog Audio I/O

Performance

Frequency Response	20 Hz to 20 kHz ±1 dB
Gain/Trim Range	Inputs: -66 to +18 dBu
Maximum Input Level	Line Inputs: +15 dBu Aux Inputs: +20 dBu
Maximum Output Level	Headphone Outputs: +21 dBu
Impedance	Inputs: 20 Kilohms (Balanced) 10 Kilohms (Unbalanced) Aux Inputs: 10 Kilohms (Unbalanced) Headphone Outputs: 3 Ohms (Unbalanced)
THD	< 0.01% (at +4 dBu, 1 kHz, Unity Gain)
Noise	-66 dB
CMRR	Line Inputs: > 42 dB (1 kHz)

Power

Power Requirements	AC Input
AC Input Power	100 to 120 VAC, 50 / 60 Hz 220 to 240 VAC, 50 / 60 Hz
Power Consumption	24 W

Physical

Rackmount Size	1 RU
Dimensions	19 x 8.8 x 1.8" / 483 x 224 x 46 mm
Weight	8.0 lb / 3.6 kg

Packaging Info

Package Weight	9.75 lb
Box Dimensions (LxWxH)	20.8 x 10.6 x 4.1"

What's in the Box: