NCTAudioStudio ActiveX DLL

From Online Media Technologies:

Create audio applications with minimal time and effort. It combines simplicity, flexibility in use and features: record, mix and playback from any sources (supports multichannel and external sound cards); convert, crop, split, merge audio files; apply about 30 audio effects (expandable by 3rd-party DSP and audio DirectX plug-ins); organize audio files into media library; implement not only file-to-file operations, but also file-to-memory, memory-to-file and memory-to-memory ones; many supported audio formats (incl. MP3, WMA, OGG, WAV, MP2, MPC, VOX, A-Law, U-Law, G.726, G.723, G.721, AIFF, AIFC, AU); adjustable visualization effects; convert text-to-speech; broadcast audio data; detect DTMF signals; use with wide range of development tools (samples and docs are included).