A new technique is introduced for synthesizing low roundoff noise second-order state-space structures. The technique yields structures which require the same number of multiplies as the canonical direct form structure. Thusnth-order realizations composed of these subfilters require only about 2nmultiplies. The number of additions required is also low, ranging from 2nto 2.5n. The synthesis of these structures consists of simple design equations and a simple procedure. A numerical example illustrating the design process is provided.