SPEAKERS - Goldmund

3. Crossover modeling and transfer function calculation
The above calculation of port and drivers sound pressure radiated at 1W/1m, enables the
crossover cut-off frequencies and slopes to be estimated.
The figures below show the example of the MiniLogos crossover modeling and transfer function
calculation.
Vm
Vtw
Rg
1 2
0
Rg
1 2
0
V+
V+
1
Cm
2
1
Rm
2
2
1
Cm1
1
2
Rm2
1
Lm
Rem
2
V+
2
V- V-
1
Rtw
2
1
Ctw
1 2
1
Ltw
2
Rtw2
2
V- V-
1
1
V+
Retw
2
10
dB
0
Hz
10 100 1000 10000 100000
-10
-20
-30
-40
-50
-60
-70
-80
4. Modeling comprising crossover, driver and enclosure lumped-constant
parameters
The points 2 and 3 lead to the final system modeling. The latter enable the filtered input
impedance and volume velocities to be calculated.
The figures below show the MiniLogos final modeling and the resulting calculated filtered input
impedance and volume velocities:
Vwr
Rg0r
Rtwr
0
Cmr
Rmr
Ctwr
Rem0r
Cm1r
Rm2r
R3r
Ltwr
R2r
Lmr
Lemr
+ -
-Bl
Bl
+
-
msmr
Rsmr
Csmr
+
-
+
-
Sd
Rtw2r Re_twr Letwr
mstwr Rstwr Cstwr
martwr
“Perfection in an imperfect world”
+ -
0
Bl
+
-
-Bl
0
-Sd
marmr
+
-
+
-
Sd
Cabwr
0
-Sd
Rapwr
0
mapwr