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Discussion Starter #1
So i settled on a UM18 for my HT with the Inuke6000DSP

I've started my box design and i'm getting different vent lengths from every design software/calculator i've tried. I downloaded WiniSD and it wont let me input the parameters for this sub i get an error msg for nearly all the driver inputs (yes i ensures the units were correct).

If i pick another randon 18 from the driver list i get yet another vent length value.

I'm planning on doing a 8-9 CU/FT box tuned to 19 hz only because thats what the spec sheet says. it will play mostly movies and TV some music.

my room is huge. Its a wide open basement. 6600 CU/FT

some help would be awesome. or should i just go with the port dims on the spec sheet and be done with it.
 

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Is this the UM 18-22 ? Are you going to use a round or slot port. I am no expert with this but i get 10 inch round port 27 inches long.
 

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Discussion Starter #3
its the UM18-22.

i think i'm going to copy the specs from the marty cube and change the shape.
 

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I am using BassBox for the design and importing the parameters from the database so i am confident with the numbers i gave. 10.5 cubic foot box. What are the specs for the marty
 

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its the UM18-22.

i think i'm going to copy the specs from the marty cube and change the shape.
was going to say, check out the marty variety.
someone in that thread may even model something for you.
 

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I downloaded WiniSD and it wont let me input the parameters for this sub i get an error msg for nearly all the driver inputs (yes i ensures the units were correct).
Try downloading and using this WinISD File.

And as to why you are getting different port lenghts when you look at other 18" drivers, its because the T/S parameters are different, resulting in different port lenghts to get the same tune.

A Martycube with a Ultimax has been done many times, so that form factor and port lenght will work just fine. And your adjustments to the driver placement will be fine too.
 

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Discussion Starter #7
i'm going with a martycube for now.

its going on the CNC router tomorrow.
 

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i'm going with a martycube for now.

its going on the CNC router tomorrow.
Nice, CNC router access huh you lucky dog..... Will be super awesome.
 

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Discussion Starter #9
Nice, CNC router access huh you lucky dog..... Will be super awesome.
Thanks! I'm trying to have the box built before the sub shows up.

i own 4 cnc routers. I just bought a new one and commissioned it last week.

here is the box designed in Solidworks. This is without the front grill.


this is with the grill in place. It will be wrapped with grill cloth.


the top removed


and a section view.


here is the layout for the cut file. 3 sheets 4 x 8. to make 2 boxes.

 
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WinISD parameters

" I downloaded WiniSD and it wont let me input the parameters for this sub i get an error msg for nearly all the driver inputs "

This seems to work for me for entering the parameters.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
This is the recommended method for entering driver parameters [if at any point you need to change the unit of a parameter simply click on the displayed unit and it will change]:
1.Enter Mms and Cms which results in Fs being calculated. If Mmm and Cms are not known enter Fs. If Fs and Mmm or Cms are known enter Fs and the other known value.
2.Enter Sd, Bl and Re. This will result in more auto calculations being made, but Qms and Qts will be blank. If Re is not available, go ahead and enter Sd and Bl.
3.Enter either Qms or Rms, whichever is available, generally Qms is available.
4.If Mms and/or Cms were not provided for input, now input Qes. This will cause some other fields to auto calculate.
5.Enter Hc(HeightCoil), Hg(HeightairGap) and Pe if available. These are not required, however Pe (RMS Power Rating) will give a good idea of how much power signal input to model with.
6.Enter the number of voice coils. NOTE: Drivers using dual voice coils may cause the Bl and Re parameters to change when changing the connection wiring from parallel to series. Be sure to monitor these when changing the connection option, but WinISD should automatically change these values properly.
7.Correct Znom (nominal impedance) if needed. Many times this will change to 6 and should be 2 or 4... or the ultimate resistance (in ohms) you intend to run based on the voice coil configuration and your connection setting (parallel or series).
8.Enter Xmax and any other missing parameters if known and continue. DO NOT change any of the blue auto calculations. If they are only slightly different, this is okay. If they are off significantly, contact the manufacturer or vendor of the driver.

~~~~~~~~~~~~~~~~~~~~~~
Nice build by the way.
 
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Discussion Starter #11
Thank you!!!!!!!

" i downloaded winisd and it wont let me input the parameters for this sub i get an error msg for nearly all the driver inputs "

this seems to work for me for entering the parameters.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
this is the recommended method for entering driver parameters [if at any point you need to change the unit of a parameter simply click on the displayed unit and it will change]:
1.enter mms and cms which results in fs being calculated. If mmm and cms are not known enter fs. If fs and mmm or cms are known enter fs and the other known value.
2.enter sd, bl and re. This will result in more auto calculations being made, but qms and qts will be blank. If re is not available, go ahead and enter sd and bl.
3.enter either qms or rms, whichever is available, generally qms is available.
4.if mms and/or cms were not provided for input, now input qes. This will cause some other fields to auto calculate.
5.enter hc(heightcoil), hg(heightairgap) and pe if available. These are not required, however pe (rms power rating) will give a good idea of how much power signal input to model with.
6.enter the number of voice coils. Note: Drivers using dual voice coils may cause the bl and re parameters to change when changing the connection wiring from parallel to series. Be sure to monitor these when changing the connection option, but winisd should automatically change these values properly.
7.correct znom (nominal impedance) if needed. Many times this will change to 6 and should be 2 or 4... Or the ultimate resistance (in ohms) you intend to run based on the voice coil configuration and your connection setting (parallel or series).
8.enter xmax and any other missing parameters if known and continue. Do not change any of the blue auto calculations. If they are only slightly different, this is okay. If they are off significantly, contact the manufacturer or vendor of the driver.

~~~~~~~~~~~~~~~~~~~~~~
nice build by the way.
 

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If you want to be economical, 2 full marty's will be the best use of your MDF money.
and the UM18 in a full Marty is a very well proven combo. lots of build threads.

http://www.avsforum.com/forum/155-diy-speakers-subs/1648673-martysub-faq.html

Also, looking at your box design you may run into some issues with your port not acting like it is designed to since it ends so close to another wall. Firstly, when doing slot ports, the tuning frequency will end up lower than the length of your port would suggest, since the boundary of the box makes the port effectively a bit longer. Theres lots of science and math on exactly how to calculate it, but in practice plan for 1-2hz lower tuning. Secondly, your port ends very close to a boundary causing a second 90 degree turn which will definitely increase chances of turbulence/port noise, and will lower your port tune a bit, since the air is traveling a longer distance.
 

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Discussion Starter #13
If you want to be economical, 2 full marty's will be the best use of your MDF money.
and the UM18 in a full Marty is a very well proven combo. lots of build threads.

http://www.avsforum.com/forum/155-diy-speakers-subs/1648673-martysub-faq.html

Also, looking at your box design you may run into some issues with your port not acting like it is designed to since it ends so close to another wall. Firstly, when doing slot ports, the tuning frequency will end up lower than the length of your port would suggest, since the boundary of the box makes the port effectively a bit longer. Theres lots of science and math on exactly how to calculate it, but in practice plan for 1-2hz lower tuning. Secondly, your port ends very close to a boundary causing a second 90 degree turn which will definitely increase chances of turbulence/port noise, and will lower your port tune a bit, since the air is traveling a longer distance.
Good info. Thanks. Should I be concerned that this box design is just a regular Marty cube? I didn't change any dims I just added the front grill plate. I really don't want to have 2 full Marty's in my room at this point. I need to break the wife into this slowly.
 

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Good info. Thanks. Should I be concerned that this box design is just a regular Marty cube? I didn't change any dims I just added the front grill plate. I really don't want to have 2 full Marty's in my room at this point. I need to break the wife into this slowly.


A marty cube is too small for the UM18-22’s. IMHO I would either switch to a sub that will work better in that cube enclosure or build a mini-marty enclosure as a coffee table or disguise it as a buffet table for WAF.


Sent from my iPhone using Tapatalk
 

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Good info. Thanks. Should I be concerned that this box design is just a regular Marty cube? I didn't change any dims I just added the front grill plate. I really don't want to have 2 full Marty's in my room at this point. I need to break the wife into this slowly.
Well obviously you'll get less output out of the Marty Cube than a full Marty. The design is fine per say, just be aware that it has some limitations/drawbacks. It'll still be able to run with stuff like SVS's Ultra 16 line no problem.
 

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Discussion Starter #16
OK. Changed to a fullmarty. I htink i will just build it and not give the wife a heads up on the size.




is there a such thing as too much bracing?

all the bracing will have full round over on the holes to keep things smooth on the inside.
 
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OK. Changed to a fullmarty. I htink i will just build it and not give the wife a heads up on the size.




is there a such thing as too much bracing?

all the bracing will have full round over on the holes to keep things smooth on the inside.
Bracing looks good. The roundovers aren't necessary and provide no benefit. However I always do it too just because I am OCD like that.;)
 

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OK. Changed to a fullmarty. I htink i will just build it and not give the wife a heads up on the size.









is there a such thing as too much bracing?



all the bracing will have full round over on the holes to keep things smooth on the inside.

Your enclosure design looks great including the bracing.
If you are worried about size in regards to your wife, you could do the mini Marty which is 4 inches shorter in height. The minimart he has a very similar response curve compared to the full Marty.


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What happens with the UM18-22 if you make Full Marty cabinet even bigger? If you scale the dimensions up a little more, including the port? Lower frequencies? More SPL?
 

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Discussion Starter #20
What happens with the UM18-22 if you make Full Marty cabinet even bigger? If you scale the dimensions up a little more, including the port? Lower frequencies? More SPL?
good question. I would also like to know.
 
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