Dot Active 2 way active design
Idea
I was last year following .Kartesian from France and really being impressed by knowledge of the designers/owners. In parallel I was choosing the right speakers for my 4-way BlockuDoku design. Due to the decisions made in the other design I stayed with Seas 22TAF/G. So I purchased 2pcs Kartesian WOM120_vMS from www.toutlehautparleur.com.
Package came after 5 days including the weekend. Good performance.
Did dirty testing in the box from the other design (92dB) and measured the speaker in a closed box.
Impedance of Kartesian WOM120
Box internal volume = 9,5l net closed
Nearfield measurement of closed box – black. 1m distance 2,83V measurement in red.
Frequency response from 154Hz. Same is visible in box simulation by WinISD. Hmmm… definitely not enough bass. So I drilled a hole there and put a bass reflex. Now we have – box internal volume = 9,5l net minus Bass Reflex; BR size 14x5cm
Comparison in box left and right. Almost identical. Good result and quality of speakers!
Quick and dirty crossover
Results:
I am impressed by the details, bass and speed of Kartesian speakers. Seas – there is no doubt – this is one of the best speakers you can buy for the money. Crossover is bad and there is a dip in the 3,5kHz region. But it makes no sense now to make corrections.
Step response
Slow settlement of the speaker is probably due to too big box and bad tuning.
Final enclosure
Enclosure size will be determined with WinISD. Definitely bass reflex design. Smaller enclosure and better tuning is needed.
Kartesian suggests 4,5L vented 60Hz tuning and after a couple of simulations I think this is the way to go.
Green: 4,5l net; Bass Reflex, 60Hz tuning, -3dB @ 58,66Hz
Red: 9,5l net; Bass Reflex, 58Hz tuning, -3dB @ 51,42Hz
Blue: closed box 9,5l net; -3dB @ 154Hz, -6dB 94Hz
Vent volume =
3D simulation
150 x 270 cm front
Tweeter 97,7mm
Bas 120mm
Process of making
Measurements:
Amplifier and crossover.
Finally I decided to pair it with a WONDOM SURE amplifier.
This one:
AA-JA33286 WONDOM JAB5 4×100 Watt Class D Audio Amplifier Board W ADAU1701 DSP & Bluetooth Ver5.0 For Audio 4.0/2.1/2.0 System
I designed LR4 Linkwitz Riley in Sigma Studio.
Final results of filter:
BAS = GREEN
TWEETER = RED
Full speaker with crossover (directivity: 0deg, 15deg, 30deg, 60deg)
Comparison Left and Right Speaker 0deg
