The KH 420 is designed for use as a mid-field or main monitor in stereo and multi-channel systems. It can be used in project, music, broadcast centers, and post production studios for tracking, mixing, and mastering.

The KH 420 three-way analog active studio monitor features a Mathematically Modeled Dispersion™ Waveguide (MMD™), flexible acoustical controls, various input options, analog class-AB amplifiers, and an extensive range of mounting hardware. This allows the loudspeaker to be used in diverse acoustical conditions, with any source equipment and in a wide variety of physical locations. The KH 420 represents the latest in acoustic and electronic simulation and measurement technologies to ensure the most accurate sound reproduction possible.

The KH 420 is designed for midfield applications and as main monitor in project, music, broadcast and post-production studios for recording, mixing and mastering. And in a multi-channel system, it can also be freely combined with all other Neumann studio monitors.

With its tri-channel amplifiers the KH 420 also realizes sound pressures of up to 122.4 dB. And it thereby retains high-resolution and neutral representation across the entire frequency response. This also includes an exceptional bass response down to 26 Hz. Despite using ports, there is no “overhang” or audible resonance in the low frequency range and the transient response is precisely controlled at all times.

The computer modeled chassis is constructed of LRIM™ materials which eliminates standing wave resonances and suppresses intermodulation distortion, especially in the midrange.

For demanding treble, our own specially developed, powerful alloy fabric dome ensures distortion-free reproduction. The fabric dome captures the midrange with utmost precision. Its ultralight material and the powerful neodymium magnet enable a significantly better transient response with considerably less distortion than comparable midrange drivers.

The Digital Input Module DIM 1 expands the loudspeaker electronics by a digital XLR input, a digital BNC input and a digital BNC output (192 kHz/24 Bit) for flexible digital signal links. With the delay function (adjustment range 0 - 400 ms) of the DIM 1, the audio signal can be delayed to ensure audio-visual synchronization (lip sync). In addition, the high resolution of the delays (0.1 ms) allows equalization of the propagation delays. The delay can be added to both inputs (digital and analog). The KH 420 can be retrofitted with a DIM 1.

The KH 420 has also been developed true to the Neumann philosophy for monitor loudspeakers. Every component, every shape, every signal and every wave motion is a consequence of this philosophy. No form or component is there without reason. There are hundreds of tangible reasons built into the KH 420, which all stand for exceptionally pure and neutral sound. These include, for example, curvatures of the housing that reduce edge diffraction. Also included is the pistonic output of the bass driver which does not give rise to harmonic distortions, even with the highest sound peaks. Some of these reasons are obvious in the KH 420. Others Neumann prefers to keep to itself. But together, each can be heard – sound professionals in both large and small studios all around the world can testify to this.

Neumann KH 420 G Features

Computer-modeled cabinet design using Low Resonance Integral Molding (LRIM™) materials
Extraordinary bass depth (26 Hz) with high sound pressure (122.4 dB)
Precise dispersion in the midrange and high frequencies
As a stereo system with KH 750 DSP and optional tools, controllable and alignable to the room
10" woofer, 3" soft dome midrange, 1" alloy fabric dome tweeter and protective grille
330 + 140 + 140 W class AB-amplifiers with thermal protection
Vented enclosure with rotatable Mathematically Modeled Dispersion™ (MMD™) Waveguide
Input gain control, output level control, ground lift
Fourth-order crossover and 4-position bass, low-mid and treble acoustical controls, and parametric EQ
Self-generated noise level <0 dB(A) at 1 m
Independent thermo limiters for woofer, midrange dome and tweeter. Woofer peak and excursion limiters.
Two-color dimmable Neumann logo
Magnetic shielding
XLR-balanced analog input
Optional digital inputs with delay feature
Universal switched-mode power supply
Full range of accessories and mounting hardware

Neumann KH 420 G 3-Way Active Midfield Studio Monitor1

Free field frequency response ±6 dB25 Hz … 22 kHz
Free field frequency response ±3 dB26 Hz … 22 kHz
Free field frequency linearity deviation between 100 Hz and 10 kHz± 1.2 dB
Self-generated noise at 10 cm (with input gain set to 100 dB SPL for 0 dBu)<20 dB(A) SPL
Sine wave output with a THD < 0.5 % at 1 m in half space 95 dB SPL (>100 Hz)
Max. SPL calc. in half space at 3% THD at 1m (averaged between 100 Hz and 6 kHz) 122.4 dB SPL
Max. SPL in full space at 3% THD at 1m (averaged between 100 Hz and 6 kHz) 116.4 dB SPL
Bass capability: Max. SPL in half space at 3% THD at 1m (averaged between 50 Hz and 100 Hz) 109.9 dB SPL
Max. short term SPL with IEC-weighted noise (IEC 60268-5) at 1 m, in typical listening conditions 109 dB(C) SPL
Reproduction accuracy between 100 Hz and 10 kHz: 100%, 80%, 50% of loudspeakers produced ±0.78; ±0.36; ±0.22 dB
Max. short term SPL with music material at 2.3 m in typical listening conditions (pair / full range) 103 dB(C) SPL
Max. short term SPL with music material at 2.3 m, in typical listening conditions (pair with subwoofer) 109 dB(C) SPL
Max. long term SPL with pink noise at 2.3 m, in typical listening conditions (single / pair full range) 90 / 96 dB(C) SPL
Max. long term SPL with pink noise at 2.3 m, in typical listening conditions (single / pair with subwoofer) 90 / 96 dB(C) SPL
Equalization: Mid 0; -1.5; -3; -4.5 dB
Equalization: Parametric EQ: Gain '+4 ... -12 dB
Equalization: Parametric EQ: Frequency Bypass, 25 ... 80 Hz; 50 ... 160 Hz; 100 ... 320 Hz
Equalization: Parametric EQ: Q 1 ... 8
Display Brightness
- White: 100%/60%/30%/off
- Red: 100%/60%/30%
Output power midrange amplifier (THD+N with limiter deactivated: 10%) 140W
Output power midrange amplifier (THD+N with limiter deactivated: 0.1%)130W
Midrange75 mm (3") with magnetic shielding
Cabinet weight when electronics remote located30.3 kg (66 lbs 13 oz) (+ 100 g (3 oz) with DIM 1 fitted)
Bass Extension (Hz, -6 dB)25
Maximum output level (dB SPL) 116.4
Max. Listening Distance up to (m) 11
Analog input(s) XLR: analog electronically balanced
Analog input impedance >14k Ohms
Max. input level +24 dBu (DIM 1: 18 dBu for analog delayed)
Common mode rejection ratio (CMRR) >56 dB @ 15kHz
Input gain control (sensitivity) 0 dB ... -15 dB
Output level control (output level in 1 m based on 0 dBu input level) 94; 100; 108; 114 dB SPL
Equalization: Bass 0; -2.5; -5; -7.5 dB
Equalization: Treble +1; 0; -1; -2 dB
Controller design Analog; active
Crossover frequency 570 Hz and 2.0 kHz
Crossover slope 24 dB/oct; 4th order
Protection circuitry Independent thermo limiters for woofer, midrange dome and tweeter. Woofer soft clip and excursion limiters. Amplifier overheat.
Infrasonic filter: frequency; slope 9 Hz; 18 dB/oct.
Display: On; Normal Operation Neumann logo “White”
Display: Limit / Clip / Errors / Protection /Boot Mute / Shut Down Mute Neumann logo “Red”
Output power woofer amplifier (THD+N with limiter deactivated: 10%) 330W
Output power tweeter amplifier (THD+N with limiter deactivated: 10%)140W
Output power woofer amplifier (THD+N with limiter deactivated: 0.1%) 295W
Output power tweeter amplifier (THD+N with limiter deactivated: 0.1%) 130W
Mains Power Supply: input voltage; frequency 100-240V; 50/60 Hz
Power consumption (230 V / 100 V): Idle 60W (+5W when DIM 1 fitted)
Power consumption (230 V / 100 V): Full output 800W
Cabinet material Wood cabinet, polyurethane waveguide, aluminum electronics panel
Cabinet surface finish; color (front / back) Painted; metallic anthracite (RAL 7021) / black (RAL 9005)
Operating conditions +10° C to +40° C (+50° F to +104° F); <90% RH, non-condensing
Transport/storage conditions -25° C to +70° C (-13° F to 158° F); <90% RH; non-condensing
Woofer 10" (265mm) with magnetic shielding
Tweeter 1" (25mm) with protecting black metal grille
Mounting points 8 x M5 on rear panel
Product dimensions (HxWxD) 25 3/8" x 13" x 17 1/2" (645x330x444mm)
External net volume 93 liters
Packed dimensions (HxWxD) 30 1/2" x 15" x 14 1/8" (775x610x590mm)