ASP.4 Revision 1.0 Printed Circuit Board


This product is a single mono ASP.4 revision 1.0 printed circuit board. A complete system requires 2 x ASP.4 PCBs, 1 x ASP.4 power/balanced input PCB, and an enclosure. You will receive a bare PCB and must supply your own components. The PCB does arrive with one mounting bracket and screws.

The ASP.4 circuit, designed by Siegfried Linkwitz, replaces the DSP in an LX521.4 speaker system. With an input from an analog source, it means that the entire signal chain can be purely analog rather than converting from A to D and back again. The ASP.4 was tested by Siegfried Linkwitz and has replaced the miniDSP in his system.

For more information about Linkwitz LX521.4 Loudspeakers as well as other Linkwitz projects, please visit


Please post any questions about this project to the ASP.4 Help Thread (restricted access, registration required). Hairball Audio, LLC does not provide support for ASP.4 products.

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