In many cases a prospective buyer of an acoustic emission system has to rely on advertisement leaflets and demonstrations by the manufacturers to choose the best among the different systems. Information from objective sources is generally not available.

This paper will help solve this problem by making objective information available. Based on the experience that has been obtained during testing with different systems, an attempt will be made to present an overview of the performance of the systems for research applications. Results that were gathered during testing with an acoustic emission calibrator as well as results obtained during laboratory testing with an acoustic emission calibrator as well as results obtained during laboratory testing in severe conditions (i. e. fatigue environment, composite materials ...) will be presented.

In the first part of this paper important aspects of the software and the software lay-out will be discussed and this from the point of view of the user: how easy is it to handle the software, what are the possibilities of the software, are there any major disadvantages, ....?

The second part will discuss the system hardware. This part will especially focus on items like dynamic range and speed of acquisition (with and without complete waveforms recording). Since these items are at present very important in commercial strategies, a comparison will also be made between the actual performance of the systems and the performance specified by the manufacturers.

In the last part some results will be presented, obtained during actual testing (mainly on composite structures) to clarify the statements made in parts one and two. Finally some conclusions will be presented, which should help future buyers of an acoustic emission system to make a choice between the different systems, available on the market.