Duke's speakers are indeed special. I own the Jazz Modules and in addition to the waveguide design and power response (summed omnidirectional response), another factor that contributes to the sound of these speakers is the fact they have negligible power compression. Duke uses pro sound drivers with the woofer being a TAD model with a alnico magnet and the tweeter using a neodymium magnet. The result according to Duke is that sound pressure levels up to 112 dB are reproduced with less than 1 dB of power compression.
When it came down to me choosing new speakers to replace my Spendor 1/2e, both Duke's and the Audio Note AN/E were on my shortlist.
When it came down to me choosing new speakers to replace my Spendor 1/2e, both Duke's and the Audio Note AN/E were on my shortlist.