Brand: MARKAVSI  Model: M4000D  Product Name: Educational Audio Processor

M4000D Interactive Teaching Audio Processor - Ideal for classroom, conference room, and training room amplification; 48V phantom power; features active gain, environmental noise processing, on-site feedback processing, and customizable echo processing function.

I. Configuration Plans and Features:

This product employs a professional audio processor, a high-power amplifier, ceiling microphones, and speakers. It is suitable for amplification in large auditoriums and classrooms where multiple high-power speakers are needed. The use of ceiling microphones offers advantages over traditional wireless microphones or conference microphones: 1. Easier management, installed in fixed positions, eliminating the need for setup and teardown before and after meetings; 2. Operates on 48V phantom power, eliminating the inconvenience of battery replacement and being more environmentally friendly; 3. Long pickup distance, allowing for a natural, relaxed speaking experience without holding the microphone; 4. One ceiling microphone can be used by multiple people without passing it around; 5. Saves investment costs; 6. Healthy and hygienic, no need to touch.

II. Overview:

This product is a professional audio processing device specifically designed for school teaching amplification and conference sound reinforcement. It incorporates self-developed technologies such as adaptive feedback suppression, configurable echo cancellation, and digital equalization to achieve long-distance microphone pickup. During use, simply install a pickup (supplied by our company) above the rostrum, and it can fully cover an 8-meter radius area. In this scenario, teachers can interact with students and conduct classes without the need for any amplification equipment.

Wide pickup range; noise in student areas doesn't affect sound amplification; loud, solid, and not hollow; no high or low-frequency hiss.

The system host provides a 48V phantom power supply, which can be directly connected to the microphone. The accompanying microphone features a high-sensitivity, high-fidelity condenser capsule with a long pick-up distance and clear, natural sound. Equipped with an exceptional digital audio processor, the product utilizes the AIITAV DSP V** high-speed floating-point algorithm from the American Silicon Valley, an adaptive algorithm combining AI, IT, and AV technologies. This enables functions such as adaptive feedback suppression, dynamic automatic noise reduction, and echo suppression, allowing for long-distance microphone pick-up and remote interactive teaching. The sound amplification is clear, noise-free, and evenly distributed across the sound field.

This system resolves the issues of traditional wireless microphones requiring frequent battery changes or charging and being prone to damage, making equipment management more convenient.

Section 3: Software

Software Features:

1. Connect and control this host via USB serial port to your computer.

2. Set the high-pass and low-pass frequency values in the software interface.

3. Set the threshold for noise gate and automatic level limiting.

4. Adjust the built-in 6-band (adjustable) equalizer frequency points.

5. Adjust the local microphone input volume.

6. Adjust the volume of the AUX input signal.

7. Adjust the volume of the AUX output signal.

4. Product Features

1): One-click setup for fully automatic operation mode; system installation requires no acoustic field adjustment; easy to use.

2): Integrated AI-based ITAV digital technology high-speed adaptive feedback suppression circuit (AFC).

3): Features an integrated Digital Echo Cancellation (AEC) circuit, effectively eliminating echoes for remote interactive teaching.

4): Built-in smart dynamic noise filter (AIITAV-ANC), intelligently filters out background noise from the environment.

5): Built-in Automatic Gain Control (AGC).

6): Equipped with built-in digital Qualcomm tuning control, allowing for adjustable voice frequency response range.

7): Built-in Digital Limiter: Prevents sudden high signals from damaging the system, while also extending the pickup distance.

8): Built-in 6-band (adjustable) parametric digital equalizer: more precise frequency point control.

9): Voice-boosting feature to enhance clarity of speech.

10): Six microphone inputs with 48V phantom power supply. Microphone 1-4 are controlled by one switch group, while microphone 5-6 are controlled by another switch group. (Microphone 1-4 feature a 4-in-1 selection, microphone 5/6 are direct pass-through.)

11): Multi-functional input/output interfaces: six inputs, four outputs. The signal from LINE IN 1 can be mixed into both line output and local amplification output, enabling the mixing of microphone voice and music signals for remote interactive teaching (transmitted via MIX OUT). The signal from LINE IN 2 is output from the local amplification. The signal from AUX IN is only output from the local amplification, without interfering with the transmission of voice. MIC OUT is only for sampling or recording the microphone signal,不受其他信号干扰; MIX OUT outputs mixed signals (local microphone signals and LINE IN signals).

12): Microphone volume/music volume and machine parameter digital adjustment, with remote control via computer.

14): Four-Channel Microphone Selector: Automatically selects and opens the microphone closest to the teacher, while automatically closing other channels. The purpose is: a) To reduce noise transmitted to the loudspeaker from the microphone, which helps maintain a quiet classroom and clear teacher's voice. b) To minimize the conditions for howling caused by sound or electromagnetic waves from the loudspeaker entering the microphone and forming positive feedback.

15): Features one-touch mute functionality. The case is equipped with a dedicated phoenix plug external mute switch interface, which can be pressed to mute the sound when needed.

16): The system features an automatic mute function. When no microphone signal input is detected, the system automatically mutes within the set parameters.

17): Offer USB connection host software, which can be controlled via computer and is compatible with RS232 connection for central control.

18): Standard rack-mount equipment with digital display screen, showing working status and spectrum.

19): ADIDSP Smart Adaptive AI ITAV Processing: Full automatic real-time dynamic operation; regardless of changes in room environment such as position, temperature, humidity, and decoration, no manual acoustic field tuning is required during system installation. Accurate, reliable, and easy to use.

V. Technical Specifications

1): Operating Voltage 220V ± 10% (AC, 50/60Hz)

2): Microphone Input Level -40dB

3): Microphone Input Impedance: 2KΩ

4): Low-pass frequency characteristics 5KHz-20KHz

5): High-frequency characteristics 50-250 Hz

6): Microphone Frequency Response 50Hz～18KHz (-3dB, with band-pass off)

7): Line frequency characteristics: 20Hz to 20KHz (±2dB)

8): Distortion ≤ 0.1% DSP Processor ≤ 0.065% (1KHz/0dB)

9): Signal-to-Noise Ratio ≥80dB; DSP Processor ≥95dB (A-weighted)

10): Microphone Gain Boost ≥ 8 dB, Max 20 dB

11): Interface Microphone Polarization Power 48V (DC)

12): Line Input Level: 0dB, Two Channels

13): Line Output Level: 0dB, Two Channels