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      05-21-2009, 01:04 PM   #1
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2 ohm or 4 ohm Earthquake SWS?

Now that I've got my amp choice figured out and I'm pretty sure I'm going to go with the SWS subs, I'm trying to decide if the 2 ohm or 4 ohm SWS would be best for my application. The amp I'm planning to use will put out either 750W @ 4 ohm or 1150W @ 2 ohm. So that means each SWS will get either 375W or 525W. My first questions is are there any differences other than impedence between the 2 ohm and 4 ohm SWS? My other question is do you think 525W per woofer would pretty much explode them being that they are only rated for 150W? I'm confident they would be able to handle the 375W with no problem since the amp gains would probably be set to minimum anyway. Headroom is great and all but there's gotta be a limit somewhere.

I have run 125W rated subs off 300W before and it was fine. The limiting factor was that the woofer would max out on excursion far before any clipping of the amp was evident. I also ran a 250W sub off 600W and it was the same thing. I'm guessing I would probably be looking at the same issue with the SWS.
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      05-21-2009, 01:35 PM   #2
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Originally Posted by 808MGuy View Post
Now that I've got my amp choice figured out and I'm pretty sure I'm going to go with the SWS subs, I'm trying to decide if the 2 ohm or 4 ohm SWS would be best for my application. The amp I'm planning to use will put out either 750W @ 4 ohm or 1150W @ 2 ohm. So that means each SWS will get either 375W or 525W. My first questions is are there any differences other than impedence between the 2 ohm and 4 ohm SWS? My other question is do you think 525W per woofer would pretty much explode them being that they are only rated for 150W? I'm confident they would be able to handle the 375W with no problem since the amp gains would probably be set to minimum anyway. Headroom is great and all but there's gotta be a limit somewhere.

I have run 125W rated subs off 300W before and it was fine. The limiting factor was that the woofer would max out on excursion far before any clipping of the amp was evident. I also ran a 250W sub off 600W and it was the same thing. I'm guessing I would probably be looking at the same issue with the SWS.
It will not matter if it is 2 ohms or 4 ohms, what matters is to not try to push the SWS-8 to reproduce frequencies in a sound level that will exceed their power handling, and because these SWS-8 are going to be crossover'd between 40HZ to 150Hz I can see that blowing them up will be easy with 525W per woofer. You will need to both keep the amp gains to minimum and keep any EQ gains to minimum within those bands to keep these woofers from blowing up.

I think that if that amp is only for the SWS-8 then it is a waste...
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      05-21-2009, 01:42 PM   #3
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The amp is a 5 ch and that just happens to be what the sub channel can put out. I can also consider going to a 6 ch that will only do 500W @ 2 ohm for the SWS but then I would lose power on my mids because the other amp does 170W and the smaller one does about 70W to the mids. BTW, the amps being considered are the Audison LRx 5.1k and 6.9. I worked out an awesome combo deal with the BitOne. Getting the 6.9 would only be $100 less than the 5.1k but if you think the 6.9 would be a better fit for the system I would be willing to give up the extra output. The mids are a/d/s 344is and tweeters are a/d/s px concepts. One thing the 6.9 has over the 5.1k is that its all class a/b. The 5.1k is class D on the sub channel.
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      05-21-2009, 02:28 PM   #4
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Originally Posted by 808MGuy View Post
The amp is a 5 ch and that just happens to be what the sub channel can put out. I can also consider going to a 6 ch that will only do 500W @ 2 ohm for the SWS but then I would lose power on my mids because the other amp does 170W and the smaller one does about 70W to the mids. BTW, the amps being considered are the Audison LRx 5.1k and 6.9. I worked out an awesome combo deal with the BitOne. Getting the 6.9 would only be $100 less than the 5.1k but if you think the 6.9 would be a better fit for the system I would be willing to give up the extra output. The mids are a/d/s 344is and tweeters are a/d/s px concepts. One thing the 6.9 has over the 5.1k is that its all class a/b. The 5.1k is class D on the sub channel.
I see... any mono SWS-8 implementation will require two 4 ohms SWS-8 wired in parallel, so the 2 ohms version is out of the picture with the 5.1k.

Personally, I would go with the 6.9 to retain the full stereo effect of the woofers and drive the front/rear/underseat woofers with it; the SWS-8s then should be the 2 ohms version, so you can get them close to their max RMS input (140W at 2 ohms vs. 75W at 4 ohms). The bit one.1 then should be free to be adjusted without choking it to protect the woofers.

Are you having any rear speakers in this system? Are you having a trunk sub? The 5.1k looks to me that would be great only for a front/stereo underseat woofer/mono trunk sub setup.
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      05-21-2009, 03:02 PM   #5
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Quote:
Originally Posted by Technic View Post
I see... any mono SWS-8 implementation will require two 4 ohms SWS-8 wired in parallel, so the 2 ohms version is out of the picture with the 5.1k.

Personally, I would go with the 6.9 to retain the full stereo effect of the woofers and drive the front/rear/underseat woofers with it; the SWS-8s then should be the 2 ohms version, so you can get them close to their max RMS input (140W at 2 ohms vs. 75W at 4 ohms). The bit one.1 then should be free to be adjusted without choking it to protect the woofers.

Are you having any rear speakers in this system? Are you having a trunk sub? The 5.1k looks to me that would be great only for a front/stereo underseat woofer/mono trunk sub setup.
The rear will remain OEM and powered by the OEM amp. I plan to route the front and rear output of the OEM HU into the bitone and then output front high, front mid and sub to the LRx. The rear output of the bitone will go back into the OEM amp. The idea I had about getting the 5.1k was to series wire the 2-2 ohm SWS to get a 4 ohm load (750W into 4 ohms). That could easily be done near the amp. Using the 5.1k in that manner would give me ample headroom without it being too insane plus give me options if I ever did want to upgrade to a sub in the trunk.
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      05-21-2009, 03:31 PM   #6
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Originally Posted by 808MGuy View Post
The rear will remain OEM and powered by the OEM amp. I plan to route the front and rear output of the OEM HU into the bitone and then output front high, front mid and sub to the LRx. The rear output of the bitone will go back into the OEM amp. The idea I had about getting the 5.1k was to series wire the 2-2 ohm SWS to get a 4 ohm load (750W into 4 ohms). That could easily be done near the amp. Using the 5.1k in that manner would give me ample headroom without it being too insane plus give me options if I ever did want to upgrade to a sub in the trunk.
The OEM amp inputs are either high level or low level 5V balanced, not low level un-balanced.

The bit one.1 outputs just low level un-balanced.

However, you can split the OEM HU outputs by using its front to the bit one.1 and leave its rear to the OEM amp. The bit one.1 can take the front two channels input and give you up to 8 channels output in whatever configuration you want.

Then you can use the 5.1k as you wish.
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      05-21-2009, 03:40 PM   #7
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Quote:
Originally Posted by Technic View Post
The OEM amp inputs are either high level or low level 5V balanced, not low level un-balanced.

The bit one.1 outputs just low level un-balanced.

However, you can split the OEM HU outputs by using its front to the bit one.1 and leave its rear to the OEM amp. The bit one.1 can take the front two channels input and give you up to 8 channels output in whatever configuration you want.

Then you can use the 5.1k as you wish.
Thanks. I wasn't totally sure if the OEM amp could take the output of the bitone. I can always leave it and just run the front outputs into the bitone like you said. It would have been nice to be able to EQ the rears too but its not a big deal since those speakers will only be heard by rear seat passengers anyway.
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      05-21-2009, 04:00 PM   #8
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Thanks. I wasn't totally sure if the OEM amp could take the output of the bitone. I can always leave it and just run the front outputs into the bitone like you said. It would have been nice to be able to EQ the rears too but its not a big deal since those speakers will only be heard by rear seat passengers anyway.
Just raise the output level on the bit one.1 (max 4V rms) without clipping to see if the OEM amp can take it.

Perhaps it can if its input is high enough.
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      05-22-2009, 03:32 PM   #9
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One more question. Where is the best place to get the SWS from? I don't have a local dealer for Earthquake. I know you posted an ebay auction that was a buy it now or best offer but I don't see that anymore. Seems like they are all the same price and shipping is going to be insane (about $40/woofer). If I'm going to end up paying close to $200/woofer, I might look at other options.
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      05-22-2009, 04:09 PM   #10
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One more question. Where is the best place to get the SWS from? I don't have a local dealer for Earthquake. I know you posted an ebay auction that was a buy it now or best offer but I don't see that anymore. Seems like they are all the same price and shipping is going to be insane (about $40/woofer). If I'm going to end up paying close to $200/woofer, I might look at other options.
This is the cheapest place that I remember... http://www.caraudiocraze.com/subwoof.../prod_762.html
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      05-22-2009, 05:18 PM   #11
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Quote:
Originally Posted by 808MGuy View Post
Now that I've got my amp choice figured out and I'm pretty sure I'm going to go with the SWS subs, I'm trying to decide if the 2 ohm or 4 ohm SWS would be best for my application. The amp I'm planning to use will put out either 750W @ 4 ohm or 1150W @ 2 ohm. So that means each SWS will get either 375W or 525W. My first questions is are there any differences other than impedence between the 2 ohm and 4 ohm SWS? My other question is do you think 525W per woofer would pretty much explode them being that they are only rated for 150W? I'm confident they would be able to handle the 375W with no problem since the amp gains would probably be set to minimum anyway. Headroom is great and all but there's gotta be a limit somewhere.

I have run 125W rated subs off 300W before and it was fine. The limiting factor was that the woofer would max out on excursion far before any clipping of the amp was evident. I also ran a 250W sub off 600W and it was the same thing. I'm guessing I would probably be looking at the same issue with the SWS.
Which amp did you end up going with??
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      05-22-2009, 07:10 PM   #12
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Which amp did you end up going with??
Looks like I'm going to go with the 5.1k but the 6.9 is still in the back of my mind. My contact is out of town until the end of next month so I'll have to wait until he gets back to make my order anyway.

There are pros and cons to both. The enormous headroom provided by the 5.1k is hard to ignore but also the fact that the SWS can only do so much has me thinking about the 6.9. If I do go with the 6.9, I can always use the sub channels on the 6.9 to run the SWS as stereo midbass and then add a mono amp and sub in the trunk if I feel the need for more bass. If I get the 5.1k and I'm not happy with the bass output from the SWS, I would end up probably getting another 2 ch amp to run the SWS stereo midbass and then use the sub channel on the 5.1k to run a sub in the trunk. I don't know which would be cheaper or easier to do later but we'll see I guess. I still think the 5.1k is the way to go.
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      05-22-2009, 10:54 PM   #13
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Quote:
Originally Posted by 808MGuy View Post
Looks like I'm going to go with the 5.1k but the 6.9 is still in the back of my mind. My contact is out of town until the end of next month so I'll have to wait until he gets back to make my order anyway.

There are pros and cons to both. The enormous headroom provided by the 5.1k is hard to ignore but also the fact that the SWS can only do so much has me thinking about the 6.9. If I do go with the 6.9, I can always use the sub channels on the 6.9 to run the SWS as stereo midbass and then add a mono amp and sub in the trunk if I feel the need for more bass. If I get the 5.1k and I'm not happy with the bass output from the SWS, I would end up probably getting another 2 ch amp to run the SWS stereo midbass and then use the sub channel on the 5.1k to run a sub in the trunk. I don't know which would be cheaper or easier to do later but we'll see I guess. I still think the 5.1k is the way to go.
Nice!!! Im VERY happy with my set-up so far. Although I am waiting for something to happen to my Bit One like it has to almost everyone else.
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