NEUMANN KH 420

Product overview

The NEUMANN KH 420 is a three-way, tri-amplified active midfield studio monitor with a rotatable Mathematically Modelled Dispersion (MMD) waveguide, a dedicated midrange dome, a parametric equaliser and bass down to 26 Hz: the gold standard in the midfield range.

Designed for working distances of 1.5 to 3 m, the KH 420 handles this space effortlessly thanks to great power reserves and precisely concentrated dispersion. Even in diverse acoustical environments it remains neutral and clear in every detail, and every sound element can be localised. Thermally protected Class AB amplifiers deliver 330 W and two times 140 W.

Key features

• Rotatable elliptical MMD waveguide for upright or horizontal mounting
• 75 mm fabric dome midrange with neodymium magnet and low stray field
• Bass down to 26 Hz without overhang; up to 122.4 dB SPL
• Computer-modelled LRIM cabinet: no standing waves, low midrange intermodulation
• 4-position bass, mid and treble controls plus a parametric equaliser (25 - 320 Hz)
• Accelerated Heat Tunneling (AHT) electronics panel; dual switched-mode power supplies
• Optional DIM 1 digital input and delay module; optional REK 4 remote electronics
• Any KH 420 is pair-matched to any other KH 420

Ports and high dynamics: no longer a contradiction

With its tri-channel amplifiers the KH 420 reaches sound pressures of up to 122.4 dB while retaining a high-resolution, neutral representation, including an exceptional bass response down to 26 Hz. Despite the ports there is no overhang or audible resonance in the low frequency range, and the transient response is precisely controlled at all times.

Precisely concentrated dispersion

The dispersion of the KH 420 is deliberately narrower to guarantee reference sound at longer working distances. Horizontally precise dispersion gives flexibility in the listening position, the narrower vertical dispersion reduces reflections from desks or consoles, and the waveguide can be rotated when the cabinet is mounted horizontally.

Digital input and delay option

The optional DIM 1 digital input module adds a digital XLR input, a digital BNC input and a digital BNC output (192 kHz / 24 bit), with a delay of up to 409.5 ms in 0.1 ms steps for lip sync and propagation delay compensation. The KH 420 can be retrofitted with a DIM 1.

Applications

Midfield applications and main monitoring in project, music, broadcast and post-production studios for recording, mixing and mastering; in multichannel systems it can be freely combined with all other Neumann studio monitors.

In the box

• KH 420 studio monitor
• 3 mains cables (European, UK and US)
• Operating manual
• Getting started quickly supplement

NEUMANN KH 420: frequently asked questions

How far away should I sit?

The recommended listening distance is 1.5 to 3 m; the feasible range is 1.25 to 11 m.

Can the KH 420 be mounted horizontally?

Yes. The MMD waveguide is rotated within the cabinet (90° the opposite way to the cabinet) so that the dispersion stays correct.

Does it have a digital input?

Only with the optional DIM 1 digital input module, which adds AES3 / S/PDIF inputs, an AES3 output and a delay function.

What does the parametric equaliser do?

It compensates for low and low-mid anomalies such as desk loading, boundary interference and room resonances: gain +4 to -12 dB, ranges 25 - 80, 50 - 160 and 100 - 320 Hz, Q 1 to 8.

Where can I buy the NEUMANN KH 420 in India?

The NEUMANN KH 420 is available from Shivansh Electronics, Kolkata, West Bengal, India, with delivery across India.

Workflow 1: Main monitoring in a control room

Studios that mix at 1.5 to 3 m.

Connections

Setup

1. Place the pair at ±30°, 1.5 - 3 m from the listener.
2. Point the acoustical axis (midpoint of midrange and tweeter) at the listening position.
3. Set bass, mid and treble for the room.
4. Correct room resonances with the parametric equaliser.

Tip: Avoid 0.8 - 2 m from the wall behind the monitors.

Workflow 2: Flush mounting

New control room builds.

Connections

Setup

1. Have the flush mounting designed by an experienced acoustic engineer.
2. Isolate the cabinet from the wall and avoid a 'picture frame'.
3. Use more bass attenuation for heavier walls.
4. Keep the electronics panel and its cabinet together (serial number behind the woofer ring).

Tip: Flush mounting reduces edge diffraction and rear-wall cancellations.

Workflow 3: Horizontal mounting

Rooms where the monitors lie on their side.

Connections

Setup

1. Lay the cabinet on its back on a soft surface.
2. Undo the four bolts and rotate the MMD waveguide 90° opposite to the cabinet.
3. Tighten to 2 Nm and refit the logo the right way round.
4. Check the sealing with a loud 32 Hz sine wave.

Tip: The rotation table is printed on the rear panel.

Workflow 4: Digital input and lip sync

Post production and broadcast rooms with picture.

Connections

Setup

1. Have the DIM 1 installed by an authorised Neumann service partner.
2. Select the input with SIGNAL SELECT.
3. Set the DELAY rotary switches for lip sync or time of flight.
4. Check the level.

Tip: Delay is adjustable up to 409.5 ms in 0.1 ms steps.

Workflow 5: Setting the acoustic level

Anyone calibrating a monitoring level.

Connections

Setup

1. Set OUTPUT LEVEL to 94 dB SPL and INPUT GAIN to -15 dB.
2. Play pink noise at -18 dBFS (Europe) or -20 dBFS (USA).
3. Measure at the listening position with a C-weighted, slow sound level meter.
4. Set OUTPUT LEVEL and INPUT GAIN for the desired level.

Tip: Film: 85 dB(C); broadcast: 79 to 83 dB(C).

Workflow 6: Large multichannel systems

Mixing stages and immersive rooms.

Connections

Setup

1. Use KH 420 monitors as front loudspeakers in mid-sized and large systems.
2. Combine freely with other Neumann monitors.
3. Align distances or delays.
4. Add KH subwoofers for more level.

Tip: Up to 111 dB SPL system level per pair with two KH 750 subwoofers (official data).