ASP.4 Power/Balanced input PCB

This product powers a set of ASP.4 revision 1.0 printed circuit boards. The power PCB also includes the option to add balanced inputs to your ASP.4 PCBs (sold separately). This set includes two custom PCB side panels for the Hammond 1455T2202 enclosure. You will have the option to select a back panel with or without balanced XLR mounting holes after you click "select options" above. You will receive a bare PCB and must supply your own components. The PCB does arrive with one mounting bracket, mounting bracket screws, and JST wire harnesses.

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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