This study delves into the identification of wire breaks in post-tensioned tendons through the application of acoustic emission testing. The research involves the evaluation of tendon wire breaks under controlled laboratory conditions and the noise analysis of an operating wind turbine. Specifically, the investigation encompasses the frequency-dependent energy distribution of acoustic signals based on Parseval's theorem. The findings reveal a pronounced concentration of energy within the frequency range of 5-20 kHz in the detected tendon wire break signals. In contrast, the operational noise signals in the wind turbine exhibit a distinct pattern, characterized by an even distribution across a broader frequency spectrum extending up to 50 kHz. This contrasting behaviour between operational noise and tendon wire breaks underscores the need for a detailed analysis within the low frequency range, specifically up to 20 kHz, for further research.