The Interface Between AES67 Studio Infrastructure and All KH Line Monitors

The compact KH 750 AES67, as a product variant of the KH 750 DSP, is the ideal subwoofer for routing audio over IP in an existing AES67 studio infrastructure all the way to the loudspeakers in a redundant and lossless manner. It thus serves as the link between the studio’s digital ST2110/AES67 data stream and all KH line monitors.

By adding more KH 750 AES67 subwoofers, stereo systems of any size can be realized. The KH 750 AES67 adds AES67 connectivity and retains all other features of the KH 750 DSP such as the unique and flexible Bass Manager as well as analog and digital inputs, four routing modes, and adaptable acoustical controls to be used in many different configurations and setups.

The KH 750 AES67 model variant offers newly integrated redundant AES67 audio network ports that are fully compliant with broadcast standards such as ST 2110 and ST 2022-7 redundancy. At the same time, the KH 750 AES67 is compatible with DANTE®-generated AES67 network streams.

The KH 750 AES67 thus enables all pairs of KH line monitors to be integrated into a redundant AES67 IP network.

More about the KH 750 AES67

In conjunction with the MA 1 - Automatic Monitor Alignment software, which is available for Mac and PC, the entire system can be precisely calibrated to suit the room character. This includes the analog monitors connected to it, which can be perfectly adapted to the room by correcting both amplitude and phase via the powerful DSP integrated in the subwoofer.

The newly designed 10” long-throw driver has a strong linear working magnet system with ELFF™ technology (Extremely Linear Force Factor™). As subwoofers are usually placed on the floor, a robust grille protects the driver from accidental damage. The ultra-compact cabinet is a closed design, which ensures the fastest possible transient response. The two analog XLR inputs are balanced as are the two analog XLR outputs. The 192 kHz / 24-bit digital input can accept AES3 and S/PDIF signals. If no signal is present for more than 90 minutes, the auto bypass function reduces power consumption to 0.3 W.

The KH 750 AES67 can be used in music, broadcast, and post production studios for tracking, mixing, and mastering.

Applications:

• Bass extension of a stereo monitoring system
• Increasing the maximum SPL of the loudspeaker system
• Decreasing harmonic and intermodulation distortion of the loudspeaker system
• Reproduction of the LFE channel
• Reproduction of the “Sub” signal of a bass managed multichannel source
• Extension for KH line subwoofer systems
• AES67/ST 2110 network integration

Advice

This device supports Sennheiser Sound Control (SSC) based on TCP and IPv6. The static IPv6 address of the device can be found using mDNS. For more information on SSC, please refer to the Sennheiser website

Please note: We do welcome the community of users implementing custom control solutions for KH monitors based on SSC. However we do not offer technical support on using the protocol and the customer support organization will not address issues with custom monitor control applications or side effects Neumann applications. Using the SSC protocol outside the Neumann applications is done at your own risk. Neumann does not warrant SSC functionality outside of the MA 1 - Automatic Monitor Alignment Application. Future firmware releases may implement a different control protocol than SSC.

Compact ultra stiff wooden cabinet

• Tough painted finish and high density rubber isolating feet
• Excellent self-damping properties leading to minimal cabinet resonances
• No standing wave resonances inside cabinet
• Tight bass sound due to very low group delay

In-house modelled long-throw bass driver with Extremely Linear Force Factor™ (ELFF™) and robust built-in grille

• Damping of break up modes brings low distortion at high sound levels
• Extremely linear force factor provides low harmonic distortion even at high excursions
• Reduced air noise and improved rocking modes
• Grille protects against mechanical damage

2.0/ 0.1 Bass Management

• Stereo and externally bass managed applications
• Bypassable 4th order crossover for maximum compatibility with consumer reproduction systems
• Allows main loudspeakers to play louder and with lower distortion

Four routing modes

• Stereo 80 Hz bass management
• External bass management
• LFE up to 120 Hz
• LFE full range

XLR electronically balanced analog inputs and outputs

• Standard interfacing to professional equipment
• Daisy chain output for subwoofer arrays

Wide range input gain and output level controls

• Easier interfacing with signal sources

position phase control, continuous low cut control

• More control in various acoustical environments
• Easy to correct room modes

Universal switched-mode power supply (100 … 240 V)

• One version works in any country and robust to poor quality mains supply

Ground lift

• Reduced noise in electrically noisy environments and overcomes ground loops

Low heat dissipation amplifiers with large headroom and sophisticated protection circuitry

• Improved transient response
• Assured reliability and safety

Separate thermo limiter to protect the voice coil and power amplifier

• Soft clip and excursion limiters
• Increases system reliability
• Allows extraction of the maximum performance from the system

Digital input and output

• 192 kHz, 24-bit conversion
• BNC connector: AES3 and S/P-DIF signals

Network connector using standard IP protocol and your existing network infrastructure

• Loudspeaker system can be controlled via the MA 1 – Automatic Monitor Alignment Software

Control function

• Toggle switch to select operation and calibration on the device or via the network with the MA 1 - Automatic Monitor Alignment software.

Input selector switch

• For switching the input source from analog / digital AES3 (automatic) to AES67

Specifications

• Free field frequency response ±6 dB: 16 … 800 Hz
• THD+N: analog, digital: < -100 dB; < -90 dB
• Free field frequency response ±3 dB: 18 … 750 Hz
• 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 (>70 Hz)
• Bass capability: Max. SPL in half space at 3% THD at 1m (averaged between 50 Hz and 100 Hz): 105.0 dB SPL
• Crosstalk (1 kHz), level matching: < -90 dB; ±0.1 dB
• Analog output(s): 2 x XLR; analog electronically balanced
• Dynamic range A-D-A: >120 dB(A)
• Dynamic range D-A: >123 dB(A)
• Digital sensitivity: -18 dBFS = 100 dB SPL at 1 m
• Latency: 1.5 ms (A-D-A linear phase); 1.2 ms (D-A linear phase)
• Phase: 0; 45; 90; 135 und 0/180 deg
• Display: Bass Management on: Green LED
• Analog input(s): 2 x XLR: analog electronically balanced
• Analog input impedance: >13k Ohms
• Max. input level: < +24 dBu
• Common mode rejection ratio (CMRR): > 56 dB @ 15 kHz
• Volume control: via Neumann.Control software
• Volume control range; resolution: 0 … -∞ dB; 0.1 dB
• Analog dynamic range; THD+N: 119 dB(A); <0.003% (-90 dB)
• Signal routing modes: Right; External Bass Management; 2 x LFE
• Digital input(s): BNC (75 Ω): AES3; S/P-DIF
• Digital output(s): BNC (75 Ω): AES3
• Digital converter: resolution; design: 16 … 24-bit DAC; Δ∑
• Digital converter: sampling rate: 22.05; 24; 32; 44.1; 48; 64; 88.2; 96; 176.4; 192 kHz
• Delay: User adjustable delay range: 0 ... 100 ms and 2 x 0 ... 20.8 ms
• Delay: Resolution: time; distance: 0.1 ms; 3.44 cm (1 3/8”)
• Delay: Max. frames Audio-video synchronisation (lip sync): 2.5 (40 ms) frames; 3 (33 ms) frames
• Delay: Time-of-flight maximum distance: 2 x 7.16 m (23' 5")
• Input gain control (sensitivity): +2 ... -12 dB
• Output level control (output level in 1 m based on 0 dBu input level): 94; 100; 108; 114 dB SPL
• Controller design: Digital; active
• Crossover frequency: 80 Hz
• Crossover slope: 24 dB/oct; 4th order
• Equalization: via Neumann.Control software: 8 x full parametric IIR + low / high shelf global balance
• FIR phase correction: For connected analog loudspeakers: Linear phase (170 Hz ... 16 kHz; +/- 45°)
• Protection circuitry: Driver (thermo limiter); Electronics (temperature limiter); Amplifier (peak limiter, temperature limiter, temperature protection and overcurrent protection); Power supply (temperature limiter and overcurrent protection)
• Infrasonic filter: frequency; slope: 17.5 Hz; 12 dB/oct.
• Remote control: Neumann.Control software via an RJ45 connector carrying standard IP data
• Display: On; Normal Operation: Green LED
• Display: Identification: Amber LED
• Display: Limit / Clip / Errors / Protection /Boot Mute / Shut Down Mute: Red LED
• AES67 Audio-over-IP Interface: Fully redundant AES67 ST2110 compliant audio network interface; 2 Fast Ethernet 100Base-TX (IEEE 802.3) RJ-45 connectors; Physical redundant network (ST 2022-7)
• AES67 Audio-over-IP input word length: 24 bits
• AES67 Audio-over-IP input sampling rate: 44.1 / 48 / 88.2 / 96 kHz
• AES67 Audio-over-IP input connection management: RAVENNA, NMOS IS-04 (Discovery & Registration) and NMOS IS-05 (Connection Management)
• Output power woofer amplifier (THD+N with limiter deactivated: 10%): 256 W
• Mains Power Supply: input voltage; frequency: 100-240V; 50/60 Hz
• Power consumption (230 V / 100 V): Standby: <300 mW
• Power consumption (230 V / 100 V): Idle: 18 W
• Power consumption (230 V / 100 V): Full output: 410 W
• In-rush current (Peak): 30 A @230 VAC
• Standby: Disabled; 90 mins (default); user defined in software
• Cabinet material: Wood cabinet, 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: 265 mm (10") with protecting black metal grille
• Product dimensions (height x width x depth): 383 x 330 x 383 mm (15 1/8" x 13" x 15 1/8")
• External net volume: 48.4 liters
• Product weight: 19.5 kg (43 lbs)