Speech and audio compression has advanced rapidly in recent years spurred on by cost effective digital technology and diverse commercial application [1, 6]. Wideband speech and high fidelity audio compression has also advanced rapidly in recent years,accelerated by the commercial success of consumer and professional digital audio products [2].
Telephone speech, wideband speech and wideband audio signals differ
not only in bandwidth and dynamic range, but also in listener
expectation of offered quality.
The conventional digital format is
PCM,with typical sampling rates and amplitude resolutions(PCM bits
per sample) as shown in Table 
.
Table: Typical values of basic parameters of three classes of
acoustic signals