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by Andrea Ciuffoli



This projects born to create an hi-efficincy no compromize loudspeaker to use with my tube amps.

The 15B100 is loaded with a 150lt bass-reflex box!

The efficiecy of the system is about 98db!

Any frequency range is reproduced without compromize!


Follows the natural D54 frequency response

and here the D54 with the tractix horn

Look about also the same result of  Michel Paquette


Follows the frequency response of the system measured with Speaker Workshop and a Panasonic microphone with the last version of the cross-over.
The low frequencies down the 100Hz should not be considered.


in this filter schematic where I have used Solen MKP 250V capacitors and Intetechnic inductances (3.3mH are with Corobar).

The woofer box has been calculated using the demo version of Akabak software.

The external size is  60 x 47 x 80 cm (d,l,h) and a 3cm MDF has been used.

The internal size is 54 x 41 x 74 cm to get about 168.8lt - 8lt (port) - 5.8(loudspeaker) = 150lt.

Follows the simulated bass frequency response.

and here including two types of roon environment.
You can note as this design has been thinking to work in a real room infact the frequency response in both rooms is quite linear.

Follows the bss-reflex port calculation