The enclosure design for this VCL EM2 is done like described in the technical pages. The SPL and impedance responses of all tranducers placed in enclosure in full space are created using the transducer datasheets. These responses will be needed for the crossover filter design.
Also acoustical and electrical measurements of the responses in full space will be done, to compare with the simulated results. The crossover design will be adapted using these measurements.
The Enclosure Design is done with VitixCAD. All the project files are saved in a VCL EM2 project directory.
All data will become available in a zip file on request.
Contents Enclosure Design
- Transducers on infinite baffle
- Transducers in enclosure on infinite baffle
- Transducer in enclosure in full space
- SPL off axis – Power and Directivity Index – full space
Transducers on infinite baffle
This design part is done like described in Tech Page 08 – VCLLabs.
SPLTrace datasheet responses
All the SPL and impedance responses of transducer datasheets are traced with the Vituix SPLTrace tool and saved as text files in the VCL EM2 Project directory. In this way the curves can be used in the further enclosure design. The curves can be imported in the Vituix main program to be displayed, like in the charts below.
SPLTrace datasheet SPL all tranducers
SPLTrace datasheet impedance all tranducers
The VituixCAD project file is saved as “VCL EM2 SPLTrace datasheet responses all tranducers.vxp”
Make TSP model
For the woofer and the midrange, TSP models are made as their low frequency responses of the datasheet are not correct.
For the tweeter, no TSP model is made as the low frequency repsonse of the datasheet is correct enough.
TSP model woofer Scanspeak 26W8534G00
TSP
Charts in Vituix Enclosure tool
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TSP model midrange SB15NBAC30-4
TSP
Charts in Vituix Enclosure tool
The SPL is saved as a text file “Vituix TSP model SB15NBAC30-8 IB SPL.txt”.
The impedance is saved as a text file “Vituix TSP model SB15NBAC30-8 IB Imp.txt”.
The Enclosure project is saved as a “vxe” file “TSP model SB15NBAC30-8 IB.vxe”
The curves can be imported in the Vituix main program to be displayed, like in the charts below.
TSP model on IB for woofer and midrange SPL
TSP model on IB for woofer and midrange Impedance
The VituixCAD project file is saved as “VCL EM2 TSP model IB woofer and midrange.vxp”
Merging SPL of TSP model and SPL curve of datasheet
For the woofer and the midrange, merging of the SPL of the TSP model and the SPL of the datasheet are made. In this way the responses of the woofer and the midrange on infinite baffle are created with correct SPL values at low frequencies.
For the tweeter, no TSP model is made. The SPL of the tweeter on infinite baffle will be chosen equal to the SPL of the datasheet.
For the merging the Vituix Merger tool is used, like described in Tech Page 08 – VCLLabs.
The SPL curves of woofer and midrange, realized with the merger tool, are saved as text files:
“Vituix Scanspeak 26W8534G00 IB SPL.txt”
“Vituix SB Acoustics SB15NBAC30-8 IB SPL.txt”
The curves of all tranducers on infinite baffle can be imported in the Vituix main program to be displayed, like in the charts below.
The VituixCAD project file is saved as “VCL EM2 All transducers on IB.vxp”
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Transducers in enclosure on infinite baffle
Placing woofer and midrange in an enclosure, the SPL and impedance responses will change, especially at low frequencies. It means the TSP model of the transducer will become different too. A TSP model of the woofer and the midrange placed in enclosure on infinite baffe must be made. The tweeter is closed at the backside, the enclosure has no impact. For the tweeter the responses on infinite baffle can be used.
This design part is done like described in This design part is done like described in Tech Page 09 – VCLLabs.
The Vituix Enclosure tool is used for this part of the design.
Transducer TSP model in enclosure – closed box radiator type
TSP model woofer Scanspeak 26W8534G00 in enclosure
For this loudspeaker VCL EM2, the woofer is placed in a 55 L closed box filled with dampening material.
In the Enclosure window:
- Select radiator type: “closed”
- While cursor on SPL chart, select “show effect of inductance” with mouse right click.
- Choose: extra mass = 0.0 g; U = 2.83 Vrms; Rg = 0 Ohm
- Choose Enclosure TAB (not the Align TAB) and set volume to 55 L, Qa = 20 and Ql = 3.6.
Under the Info TAB, a complete read out of the closed box system parameters is displayed.
Charts in Vituix Enclosure tool
The SPL is saved as a text file “Vituix VCL EM2 TSP model Scanspeak 26W8534G00 Enc IB SPL.txt”.
The impedance is saved as a text file “Vituix VCL EM2 TSP model Scanspeak 26W8534G00 Enc IB Imp.txt”.
The Enclosure project is saved as a “vxe” file “VCL EM2 TSP model Scanspeak 26W8534G00 Enc IB.vxe”.
TSP model woofer SB15NBAC30-8 in enclosure
For this loudspeaker VCL EM2, the midrange is placed in a 6 L closed box filled with dampening material.
In the Enclosure window:
- Select radiator type: “closed”
- While cursor on SPL chart, select “show effect of inductance” with mouse right click.
- Choose: extra mass = 0.0 g; U = 2.83 Vrms; Rg = 0 Ohm
- Choose Enclosure TAB (not the Align TAB) and set volume to 6 L, Qa = 30 and Ql = 16.
Under the Info TAB, a complete read out of the closed box system parameters is displayed.
Charts in Vituix Enclosure tool
The SPL is saved as a text file “Vituix VCL EM2 TSP model SB15NBAC30-8 Enc IB SPL.txt”.
The impedance is saved as a text file “Vituix VCL EM2 TSP model SB15NBAC30-8 Enc IB Imp.txt”.
The Enclosure project is saved as a “vxe” file “VCL EM2 TSP model SB15NBAC30-8 Enc IB.vxe”.
Merging SPL of TSP model in enclosure and SPL curve of transducer on infinte baffle
For the woofer and the midrange, merging of the SPL of the TSP model in enclosure and the SPL of the transducer on infinte baffle are made.
For the tweeter, no TSP model is made. The SPL of the tweeter in enclosure on infinite baffle will be chosen equal to the SPL of the datasheet.
For the merging the Vituix Merger tool is used, like described in Tech Page 08 – VCLLabs.
The SPL curves of woofer and midrange, realized with the merger tool, are saved as text files:
“Vituix Scanspeak 26W8534G00 Enc IB SPL.txt”
“Vituix SB Acoustics SB15NBAC30-8 Enc IB SPL.txt”
The curves of all tranducers on infinite baffle can be imported in the Vituix main program to be displayed, like in the charts below.
The VituixCAD project file is saved as “VCL EM2 All transducers Enc IB.vxp”
