[JoelTW]

Hi, this is my first post and I'm a newbie to HT stuff.

For a little introduction, I'm 18 years old and just recently became interested in "nice" speakers... Since I'm not so rich, I purchased a set of Klipsch ProMedia 5.1 speakers (for $358)...

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What I want to do is build a subwoofer to extend the low-end, if possible. I connect this 5.1 set of speakers to my computer with 3 stereo minijacks and the 3rd one is Center/LFE...

Is it possible to split the LFE to both inputs, and what connections would I have to get?

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The subwoofer I am planning to build is a "sonosub" with a 12" adire shiva driver and a 250 watt parts express amp. Any suggestions on cubic feet for this? Adire sells a kit with a grill, connectors, and port/etc

My budget is around $300 maybe a little more

[Jonathan M]

Yes, you will be able to split the LFE signal out to both the ProMedia and your new Sonosub.

Firstly, use a stereo miniplug (3.5mm) to twin RCA lead out of the computer's soundcard. This splits the Centre off the LFE. Then connect a female-female joiner to the Centre RCA (You may not know which one - just choose one as we can swap it over later if necessary.)
Then connect a RCA to 3.5mm stereo socket lead from the centre RCA to your current Promedia stuff. Connect the other RCA from the first lead to your new sub amp. You may need a couple of gender changing plugs - I don't know what is available in the US, but all the above is available in New Zealand, so you should be OK.

If you don't mind manufacturing your own cable, this can be done as well.

As for volume of enclosure, decide if you wanna go ported or sealed, and what sort of bass sound are you going for? (Low and flat, high impact etc. etc.)

Hope this helps.

[Frank Carter]

Here's some enclosure suggestions from Adire's site:

http://www.adireaudio.com/tech_papers/shiva_apps.htm

[JoelTW]

Thanks for the input!

I'm looking for rumble in movies but clean bass for music, if this helps you decide what is best for me.

I believe the promedia sub farts at loud volumes, hehe, so maybe I can relieve it with a new sub helping.

Punchy bass sounds good to me, but I also want good rumbles in movies

Also, I don't want a sonosub the size of a water heater

[JoelTW]

Jonathan,

Can I still use the sub in the ProMedia? The picture of the back of the sub is here: http://www.3dsoundsurge.com/reviews/...51sub_rear.jpg

I'm guessing the new sub amp has RCA out as well. So, then I would need 1/8" stereo male -> male/female RCA from source, male RCA going to new sub amp. Then another 2 male RCA -> 1/8" stereo male, one RCA from new sub amp and the other continuing the Center to the other sub/amp.

I just need to find the wires now, if this is correct

[Jonathan M]

Yep that's right.

If the new sub has no outputs, you can use a y-splitter to split your LFE RCA into two.

You may (likely) find that the Shiva (or whatever) outperforms the other sub so much as to not bother with it.

[JoelTW]

cool!

I just had a brilliant idea...

I can get 1/8 mini-> male RCA splitter, 2 of them... then just link the Center with an RCA "coupler"... should be the simplest solution, right?

Is there any static noise caused by this in subwoofer application? :b

I still am really new to this and don't understand how the volume affects punchiness and loudness, etc... Would you still recommend building a sonosub (I thought that was the easiest to make)?

[David Lorenzo]

I have ProMedia 4.1's. The sub that it comes with doesn't deserve to run with a sub like the Shiva. Don't even bother running both of them. Don't get me wrong. For a sub that's part of a PC speaker set it's great, but below about 30 hz the output drops like a rock and the output above 30 hz isn't very articulate.

[Chris Tsutsui]

Here's a suggestion..

Open up the Klipsch sub and unhook the postive wire to the subwoofer driver. This will simply turn off the subwoofer yet allow the other speakers to play.

Use the 5 speakers from the Klipsch Promedia as satellites that are still hooked to the sound card and to the Klipsch amp, then use the LFE out on your sound card to go to your shiva. (You will have to separate the LFE from the Center using adapters)

So basically you'll be using the Klipsch amp to only power the satellites (which may get more power now that they don't have to power the sub) -- And use the PE250 amp to just power the Sonoshiva.

Adjust the crossover and levels, and enjoy.

Reason I say this will sound best is because the Klipsch sub and shiva sub don't mix. It'll be like hearing deep accurate bass with an overlapping layer of ear fatiguing boom (from the klipsch). Not saying the promedias are bad, were just comparing tiny to shiva.

[JoelTW]

I'm afraid that opening the sub will void warranty, and these things are likely to blow out (if you do a little research).

I think I could just leave it disconnected or lower the volume of it. By the way, the ProMedia 5.1 sub/amp is supposed to be better than the 4.1 set.

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I'm guessing PE is parts express Is the package with the remote and extra controls worth it?

Thanks for the help

[JoelTW]

I found something cool at PE.

http://www.partsexpress.com/pe/pshow...=300-739&DID=7

It's basically a kit with the box already made. 10" titanic

Looks like a reasonable price but I don't know how it compares to a 12" shiva?

Should I get gold plated stereo1/8" to RCA splitters?

THANKS for any answers...

[TimForman]

I recommend going with the Shiva in a 18"x32" sonotube, 4"x12" port tuned to 21.7 Hz. This will give you nice flat low response without a huge footprint.
Shiva - $125
S-tube- $20
Amp - $120
Port - $14
and depending on your finish, glue, paint, etc, it's possible to come in pretty close to $300. Not bad for an excellent performer!