The performance of watermarking schemes based on correlation detection is closely related to the frequency characteristics of the watermark sequence. In order to improve both detection reliability and robustness against attacks, embedding of watermarks with high-frequency spectrum, in the low frequencies of the DFT domain, is introduced in this paper and theoretical analysis of correlation based watermarking techniques with multiplicative embedding is performed. The proposed watermarking framework is successfully applied to audio signals, demonstrating its superiority with respect to both robustness and inaudibility. Experiments are conducted, in order to verify the validity of the theoretical analysis results.