Frugel-Horn Mk3 Builds & Build Questions

[nandappe]

My choice , final adjustments.

Minimal sound absorbers.
Dump-duct Area:91cm2(6.5x14cm) , Length:10cm






My FH mk3 is thunder and storm sounds.
7HD+Frugel Horn - Final adjustment version [ My Final Choice ]---------Damp-Duct (S:91cm2 , L:10cm) - YouTube

[Scottmoose]

Originally Posted by alsyd

This is really interesting! Can someone please explain the thinking behind a ‘Damp duct’?

He's changed the internal low-pass choke into a duct to lower tuning. While it does achieve that, it also entails some compromises that haven't been mentioned and are somewhat at odds with the design goals, so it's not something I would recommend to others (while acknowledging that it suits nandappe).

The 2KHz aspect is either another minor difference from measurement setup (no criticism implied -you can get such changes through something as simple as different atmospheric conditions), or possibly from adjusting the damping & killing an internal reflection: the enclosure does not operate that high in terms of producing output, and FH3's damping scheme is designed to be user-adjustable.