ASP.4 Revision 1.0 Printed Circuit Board Set


This product is a stereo set of ASP.4 revision 1.0 printed circuit boards. A complete system requires these PCBs, 1 x ASP.4 power/balanced input PCB, and an enclosure. You will have the option to add a balanced in/power PCB once you click "select options" above. You will receive two bare PCBs and must supply your own components. The PCBs do arrive with two mounting brackets 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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