Hello! I'm new in this forum and this is my first post .
I have four sound monitoring microphons which I want to install in four different rooms and I want to hear this rooms from a fifth room by my head-phones.
The microphones it seems like this

Can I connect the microphones parallel?
Can you give me some advice on how to do that in correct way so as to avoid the noise and to hear loud and clear?

This microphones have embedded amplifier ( when I connect my headphones to one microphone I can hear clear and loud).

Thank you in advance!

 

In this case I would not connect them in parallel. There is a better way but a link to the mic module would help or a larger photo of the PCB.
SG
EDIT: found better image looks pretty close to the above.

 

TQ-008

☞Technical parameters:

The product uses high-fidelity low-noise processing chip, through multiple frequency selective suppression of environmental noise and high-frequency interference sound, echo cancellation cavity effectively reduce the serious echo of empty room, to achieve perfect radio. Tone pure, dynamic and powerful, built-in automatic gain control (AGC) circuit carefully designed. Adapted to banks, prisons, examination rooms, shopping malls, industrial production and other pickup places, with low noise, high fidelity, wide operating voltage range, low power consumption, long transmission distance and so on. TQ-008 is a new type of pickup with adjustable sensitivity. It is the ideal product for television monitoring and security system. It can be used in conjunction with video camera for video and audio synchronization. Monitor range: 5m2--150m2

☞The main parameters:
◆ Wiring: Red: 12V power supply, white: then audio signal
◆ working voltage: DC 5V ~ 12V
◆ Current consumption: 12mA
◆ Frequency range: 300 ~ 5kHz
◆ Frequency response: 2-5dB
◆ Output impedance: 600 Ω
◆ Output level: 0 ~ 6V
◆ Appearance Size: Φ = 69mm, h = 39mm
Advantages: the signal transmission line with a core shielded cable is the most ideal, copper Φ = 0.3mm2 can pass 600 meters.

☞Features:
1, built-in DSP noise reduction circuit
2, imported IC, coupling capacitor
3, the surface relief design to reduce reflection
4,2 mm pinhole design
5, Japan imported silver plated microphone
6, dynamic closed-loop noise reduction circuit

☞ Package includes
1 detector
1 spare probe (gift)
1 manual

☞ Package list:
1pcs pickup

sku：SYQ2496

 

Advantages: the signal transmission line with a core shielded cable is the most ideal, copper Φ = 0.3mm2 can pass 600 meters.

In this case a shielded 3 wire cable from each module to a mixer-headphone amp should work. I would think that the output impedance of the module is fairly low if you can drive a set of headphones which is why I don't think you can connect them in parallel.
SG
EDIT: "The product uses a high fidelity low-noise processing chip", but not just any chip it's a, "Israel high-fidelity/low noise processing chip".

 

Ermes, can you get the number off the IC chip in the module?
SG

 

The outputs of the microphone modules must be connected to an audio mixer circuit that can feed your headphones.