Gathering video evidence is certainly more preferred in surveillance equipment, but by no means is it the height of spyware development. No doubt collecting visual evidence is a great feat, but positioning it is a hindrance because if it is not positioned correctly, it is basically useless.

Comparatively, Audio surveillance listening devices have a wider range and a better sound quality. With the proper frequency and decryption machines, no one other than the buyer can hear what the target is saying.
Surveillance equipment listening devices are able to give their consumer vital information because they focus solely on sound recording.

1. Types of Devices:

There are three main categories for spy equipment listening devices, all of them simple and easy to use.
The first is more preferred and has a wider range, the ‘bugs’ or wireless transmitters. These have an unlimited range and can be activated from anywhere in the world. By dialing a simple number, the client can listen in on any conversation with exceptional sound quality.

The second is more interesting; recording devices that are small enough to be hidden on your person, for example inside your clothing or watch. For a more covert operation, these devices can be disguised as pens, smoke alarms, watches, clocks and even calculators.

Some of these are so small and well engineered that they can be hidden inside wall sockets, recording whatever the target says and whatever conversations they have.

The third is a microphone that goes beyond the simple mic, with features that enable the listener to either record or listen to conversations in various rooms. Some of the more interesting devices are capable of listening through walls, with powerful microphones that can pick up on the smallest sounds.

2. Who Uses them?

These devices are able to give their clients satisfaction on both a personal and forensic level. In the domestic atmosphere working parents can keep an eye on their baby sitters, listening in on what they say and do.
Companies can keep a track on the conversation of disgruntled employees and those they can suspect of espionage or money laundering through the use of spy equipment listening.

At a serious level, government agencies and federal agents use this piece of equipment to spy on suspected people and terrorists. Their agents listen on their plans and form counter attacks, even from miles away because some listening devices can transmit from all around the world.

Unlike cameras, a listening device can be placed wherever in the room. The high quality voice recording can give information clearly and unless they made soft clicking noises, they cannot be discovered.
The range and feature of secret listening devices are immense. They can listen, record and later playback if that is what the client desires. They are small and easy to use, easy to install and have a longer battery life and have a wider variety, all fitting the needs of the buyer. Hence, they make the best choice whenever discretion is required in surveillance cases.