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Discussion Starter #1 (Edited)
SubWoofer Build - Full Marty . Plz...be my Guide.

Hello all,

Time to build Wooferage for my HT.

Plan:
2 Full Marty with UM 18-22 on the front stage between HTM12's (LCR)
Behind AT screen and vents open towards Left and Right Speakers

Available max space for box dimensions: 20" x 30" x 60"

Appreciate any guidance/ validation on the following..

1) Box Design
2) Amps
3) Parts and Connections.

Will be buying Umik, and start toying with WinISD, Cutlist that I just downloaded. would like to learn as I go.

Regards,
 

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Discussion Starter #2 (Edited)
WinISD Parameters help

Building a Vented FullMarty with UM18-22 driver

1) Error Messages when loading Driver - " Driver Data fails integrity Check" (see pic attached)

2) what is the correct selection for alignment to choose in WinISD
 

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Building a Vented FullMarty with UM18-22 driver

1) Error Messages when loading Driver - " Driver Data fails integrity Check" (see pic attached)

2) what is the correct selection for alignment to choose in WinISD
Try this:


Enter in this order and let it auto calculate. Just hit tab after you enter your numbers. The small differences won't matter. Make sure the units are the same between your specs and the software. You don't want to enter cubic feet if the unit is liters.

Qes, Qms, Fs, Vas, Mms, Re, Xmax, Pe
 
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Discussion Starter #4
Thank you. That worked.


What is the program to use for Box Design that calculates the dimensions/ net and port volume including the braces?
 

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A spreadsheet :)

Use WinISD to dictate your port cross section area and length but then the enclosure can be any shape. So you kinda just got to mess around with the dimensions until you have the volume and foot print you want while being able to accommodate the port WinISD told you you needed.
 
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Discussion Starter #6 (Edited)
SNcube SubWoofer Build - Full Marty mod...UM18-22 WinISD results

WinISD gurus:- Please validate/ suggestions for my WinISD modelling parameters and graphs

Box Dimensions: 20"x 31.5"x 48" (outer)
Net internal Volume: ~15 cuft
Tuning: 13 hz and HPF 2nd order at 12 Hz Cutoff

Recommended vent: 2.75" H x 17.75 W and 46" port length
System input Power: 800 Watts
 

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@smcmillan2 , I did not pick the Q value on the HPF. I am thinking it was defaulted. Should it be something different?
Yeah, that was my bad, thinking of another parameter. That is the default.
 

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Discussion Starter #11 (Edited)
LLT SubWoofer Build - Full Marty to bigger. Plz Guide.

Please validate attached Specs and graphs.

Box Dimensions: 20" x 30" x 64" (DxWXH)
Volume at 19 cu.ft tuning at 14 Hz

Ports: 2 @ 3" X 8.875"; Port Length: 34"

1st PR came to ~198 Hz

The Box design with Port and corresponding graph are attached.

Thank you for the advice..


@LTD02
@eng-399
 

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that seems to be in the right ball park. for slot ports, subtract the port height from the calculated length to get the measured length. in your case that means a final port length of around 31" or so for a 14Hz tune. but if you go for 34", no big deal. tuning may come in a hair lower, that's all.
 

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the rms on the um18 is 1000 watts. your model shows 800, so you may wish to increase port size a bit to keep air flow down when going to higher power.

since you probably don't need your first port resonance up around 200hz, a little larger (and longer port) probably gives a better overall result.

i'm not sure if the port aimed up like a smokestack might not flow a hair better than having the right angle bend right at the end. every little thing though... :)
 
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