AgsAudioSignal is the object orientated representation of your audio data. It has a GList with data pointer to audio buffers. There convenience functions to resize the stream.
There exists a safe resize function because the audio signal might be in use and it doesn't allow to shrink beyond used entries. This could be fatal if an effect processor is using the stream and it gets freed as it uses it.
ags_audio_signal_duplicate_stream() can be used to blue-print one audio signals buffer to an other audio signal. Or you might call ags_audio_signal_get_template() from your AgsRecycling internal GList of audio signals to get the template.