WinISD What does this mean?

mushtafa

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Right guys, thinking about making my own sub. I've got an old Alpine driver I could use.
I've punched the details into WinISD, it made a lovely graph for me and I don't know what it means. :facepalm:
It's given me a volume for the enclosure of 30.54 litres.

Does this look any good?

Also, the driver is rated at 200wrms, will I need an amp this powerful?

Thanks
 
The picture might help :facepalm:
 

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The resulting model has many graphs, but the one it generally shows you first is the TFM one. Its basically a measurement of the subs performance, and the figure generally quoted is the one where the horizontal -3 line is. The lower the frequency here is a bit of a guide as to how low your sub will go, but how that translates into real world terms depends on the type of sub your building, and how much performance your driver is actually capable of.

The ones to read that will mean more to you are the SPL graphs (how loud you can expect it to go) and the cone excursion one, which will indicate the stress on your driver for any given amount of input. You can change the graph type in the top let drop down selection button on the graph.

In respect of the power your sub takes, there are two ways to read it. One is the wattage your driver (the actual speaker) can handle and one is the power your sub can take before damaging the driver. Your driver is rated at 200 watts, so the voice coils thermal handling capabilities max out there. It can probably handle a little more but its a good figure to work to. Thats the first way to read it. Now the second way is to look at the reaction of the driver for a given input. Once your sub is built, the larger the cabinet is past optimum size the less power the driver will need to reach max excursion. Increasing the cabinet size like this will result the built sub actually requiring less power to max it out.

We dont know anything about your sub really, other than the driver. What kind of sub are you building, sealed of ported etc, and what do you intend to power it with. Also, for help interpreting the graphs, it will be easier if you post an image of the graph you need help with and we take it from there, that we you dont have to read loads of info and try relate it to stuff you have to try imagine.
 
The picture might help :facepalm:

That helps :smashin:

Now I know your building a sealed sub. Where it says transform function magnitude, click this and change the graph to show spl, and then again for cone excursion. Show us these 2 as well. Also, in the box that you input the models details in, change it in one picture so we can see what power you have modelled it with. Thats should give us all the info we need to give a good account of our model. BTW, 200 watts isnt all that much for a sub these days.
 
To be honest I really don't know anything about this software. (Or subs by the look of it). I thought as long as the box was the right size it would be OK.

I've included the two extra graphs, I've put the input signal at 200W. (still not 100% sure what I'm going to use yet, may not be this powerful).

I know this isn't going to be great, I just need something until I can afford another one. (I hate the lack of bass, sounds crap!)

I have also included the driver specs.
 

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  • Cone excursion.JPG
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OK, your model is no good. Your sub drivers is blowing itself before 80 hz. Let me look at the driver for you and see what I can come up with.

<edit>

Ive had a play, and TBH, if you have speakers that are anything like OK this really isnt going to add anything. If your using tiny sats however you could se it for bass, but its not going to be a proper subwoofer. I cant get sealed box to handle more than 50 watts in a box of only 10 Litres. To get the most from it its going to need a ported enclosure, but even then its not going to be much better than any half decent speakers.
 
Last edited by a moderator:
OK, your model is no good. Your sub drivers is blowing itself before 80 hz. Let me look at the driver for you and see what I can come up with.

<edit>

Ive had a play, and TBH, if you have speakers that are anything like OK this really isnt going to add anything. If your using tiny sats however you could se it for bass, but its not going to be a proper subwoofer. I cant get sealed box to handle more than 50 watts in a box of only 10 Litres. To get the most from it its going to need a ported enclosure, but even then its not going to be much better than any half decent speakers.


Thanks for the advice. My front speakers are Wharfedale floorstanders and sound lovely.

I've set my DSP-A595 amp to output bass to the main speakers rather than the sub and they produce nice bass when in stereo. As soon as I switch to any of the effects including Dolby Digital, the bass drops off big time.

Anyway, thanks again :thumbsup:
 
Thanks for the advice. My front speakers are Wharfedale floorstanders and sound lovely.

I've set my DSP-A595 amp to output bass to the main speakers rather than the sub and they produce nice bass when in stereo. As soon as I switch to any of the effects including Dolby Digital, the bass drops off big time.

Anyway, thanks again :thumbsup:
Make sure the amp knows no sub is connected, the bass wont drop off then.
 
Thats the difference between stereo and surround for music. I always run stereo for music.
 
It will be 3 db louder as long as you put in twice the power, which wouldnt be a problem. What would be the problem is it wouldnt make it sound any different, and it wouldnt go any deeper.

Still not much point to be honest for use as a proper sub woofer.
 

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