The Nami, wave in Japanese (and candy or yummy in Finnish – thanks to our friend Saku for the tip), are a funny project based on the Dayton Audio ND65-8 loudspeaker, a tiny 2 and a half inches driver with aluminium diaphragm, neodymium magnetic motor and long excursion underhung voice coil.
These are the parameters declared by the manufacturer while below I report those measured with the Clio system:
| Nominal Impedance | 8 Ω |
| Fs | 98.14 Hz |
| Re | 7.50 Ω |
| Sd | 15.6 cm² |
| Qms | 3.34 |
| Qes | 0.62 |
| Qts | 0.52 |
| Cms | 1.1488 mm/N |
| Mms | 2.2892 g |
| Rms | 0.42 Ωm |
| Bl | 4.14 N/A |
| dBspl | 79.78 |
| VAS | 0.3904 L |
| Zmin | 8.12 Ω |
| L1kHz | 0.62 mH |
| L10kHz | 0.47 mH |
The Nami have been very useful to experiment with sandwich construction. The wood used for the body is birch plywood (7 layers of 12 mm each), while the front and back panels are made of black lacquered 10 mm thick MDF. The development in length of the line is about 64 cm and the total volume just over one liter.
The frequency response is correct and linear up to 10 kHz while beyond is a bit lacking.
It’s obvious that a 2-1/2″ driver can’t do everything, but what it does, does very well.
It’s an unpretentious design, but the low frequency extension (unsuspicious for such a small speaker) and a really nice midrange make it an excellent candidate as a PC audio monitor or for a super portable HI-FI system. I have listened to them for a long time in combination with the DTA-120BT amplifier and I have to say that their greatest value is their ease of listening, never tiring even in very close range.
Construction requires the use of a CNC router. It is advisable the construction of a jig to drill the holes of the mother screws that hold the screws of the front and rear panels. In a second version, which I built for some friends, I reduced the number of screws on the panels to six.
Below you can downoad the vector pdf to create the tool paths:
Andrea Rubino
