Link for Frugel-Horn XL plan

FHXL plans are made available in exchange for a donation to diyAudio.com -email Dave P10 with a screenshot of your donation receipt & he will forward a copy of the pdf planset to you. Just to stress: this is a forum donation; neither Dave nor I receive anything for it.

FHXL however is too small for the Lii unit; it was designed for a moderate range of drivers in the 5in - 6in category, with middling Q and Vas values. Even assuming the Lii data is accurate (unlikely based on available evidence) it will require a different / larger load, and with a mass corner of 136.36Hz assuming a pure voltage source does not really need a bass horn.