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      03-28-2011, 02:14 PM   #1
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Do I want SWS-8x or SWS-8xi ?

SWS-8x = 4 ohm
SWS-8xi = 2 ohm

http://www.earthquakesound.com/pdf_m...sws-manual.pdf

SWS-8x/SWS-8xi
Speaker diameter = 8"
Mounting depth = 2 1/8"
Cut out mounting hole = 7 7/8"
Weight = 8 Lbs
Voice Coil diameter = 1.5"
Aluminum bobbin
Power rating RMS = 150W
Power rating MAX = 300W
Revc = 8=3.76 Ohms / 8Xi=1.76 Ohms



Which one will yield more bass and have more options for a smaller (physically) digital Amp?

MSRP on the x (4ohm) is $175
MSRP on the xi (2ohm) is $199
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      03-28-2011, 03:48 PM   #2
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what amp are you using?
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      03-29-2011, 04:29 PM   #3
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I dont have an amp for this yet.

I own a McIntosh MC431 (4x100w) ..i should sell it.. cause its too big and heavy to install for these 2 underseat sub upgrades.

I want a nice good quality, small/compact 2-ch digital amp like an Alpine 2x150 or a JL Audio 2x150 to drive the underseat subs ...and am trying to find out which sub speaker (2ohm or 4ohm) will yield a punchier, deeper bass output.
Then i can match an amp to it
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      03-29-2011, 07:49 PM   #4
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i don't know that 2 or 4ohm will make a difference in the sound.
depends on the amp, again.
if it's class d, then it puts out the same power into 4 ohm or 2ohm
so no difference there.
but it will consume double the power at 2ohm, so unneccesary drain on the battery.

i'd say if it's a class AB amp, get 2 ohm
if it's class D get 4ohm
i have a 1ohm stable amp, so i got 2ohm and running them in parallel
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      03-30-2011, 11:14 AM   #5
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Quote:
Originally Posted by kmarei View Post
i don't know that 2 or 4ohm will make a difference in the sound.
depends on the amp, again.
if it's class d, then it puts out the same power into 4 ohm or 2ohm
so no difference there.
but it will consume double the power at 2ohm, so unneccesary drain on the battery.

i'd say if it's a class AB amp, get 2 ohm
if it's class D get 4ohm
i have a 1ohm stable amp, so i got 2ohm and running them in parallel
That just adds more questions for me...
My concern is with 'sound' i want the best bang for the buck.

- are the oe underseat subs wired direct or parralel?

- what wiring setup will yield the punchiest, deeper bass -- parralel or 2-ch direct?

- is there a class AB amp that compares to the d-class amps' physical lightness, compact structure for my 'underseat sub replacement only' setup?

- would i hear or feel an audible difference if i upgraded the underseat subs between a d-class 4ohm and an AB class amp?

Thanks ahead for your time.
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      03-30-2011, 11:53 AM   #6
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SWS-8Xi with a Rockford P300-2 will be a great bang for the buck. You should keep the woofers wired in Stereo as they have the most midbass duty in the system, however I doubt that you will notice too much of a difference if you use a mono amp (SWS-8X wired in parallel then).

You will need a 30V LOC for your Enhanced Audio system as the interface/converter, though.
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      03-30-2011, 08:58 PM   #7
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Quote:
Originally Posted by Technic View Post
You will need a 30V LOC for your Enhanced Audio system as the interface/converter, though.
What do you recommend for this? I've also heard that the 2011.5 changed things a bit so the interface people were using is prior years is no longer working. But I might be way off and fuzzy on those details.
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      04-02-2011, 08:48 AM   #8
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Quote:
Originally Posted by mastek View Post
That just adds more questions for me...
My concern is with 'sound' i want the best bang for the buck.

- are the oe underseat subs wired direct or parralel?

- what wiring setup will yield the punchiest, deeper bass -- parralel or 2-ch direct?

- is there a class AB amp that compares to the d-class amps' physical lightness, compact structure for my 'underseat sub replacement only' setup?

- would i hear or feel an audible difference if i upgraded the underseat subs between a d-class 4ohm and an AB class amp?

Thanks ahead for your time.
Mastek, one thing to consider if you are paranoid. A lower impedance load will typically be harder for the amplifier to control (damping). You will get a little bit tighter bass at low frequencies (theoretically) with a higher impedance load - so I'd choose the 8ohm units. You may need a larger amp to get the power levels you want.

Also, I would stay away from a class AB amp if you are in a hot climate. 1) You do not want to add any heat to the trunk and kill the OEM amp, which has already shown its colors w/r to heat. and 2) Class D amps are smaller, more efficient, and can themselves run in harsher conditions (because they don't add much heat to their environment).

I can't tell a difference between mono/stereo in my car. The sws subs need to be crossed over at around 100-120Hz, which in a car environment will have little effect on channel separation with the subs 3 feet apart. The OEM units were working in the 200-250Hz mid-bass range, which is a different story.
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      04-02-2011, 08:50 AM   #9
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Quote:
Originally Posted by Big Mark View Post
What do you recommend for this? I've also heard that the 2011.5 changed things a bit so the interface people were using is prior years is no longer working. But I might be way off and fuzzy on those details.
I got technic's passive LOC - and it's a really nice piece - very well thought out and basically plug and play.

No idea about 11.5 though.
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      04-02-2011, 11:14 AM   #10
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Quote:
Originally Posted by Big Mark View Post
What do you recommend for this? I've also heard that the 2011.5 changed things a bit so the interface people were using is prior years is no longer working. But I might be way off and fuzzy on those details.
The Enhanced OEM amp physically changed by MY2010, removing the 12V and the ground wires from the main 20-pin connector to a separate 2-pin connector. My harness uses only the 20-pin connector and its 12V and ground pins to provide the remote turn on signal (by a signal sensing circuit in the LOC).

Therefore there will be no remote signal from the LOC using my harness in this particular OEM amp. However, the harness LOC still will be safely converting the 30V peak woofer signal into low level signal for the aftermarket sub/woofer amp. The remote signal should be obtained from pin 13 in the back of the iDrive.

Even the "old" OEM amp with the 12V and ground signals in the 20-pin connector have issues triggering the remote signal thru signal sensing circuits -regardless of passive or active LOC. The voltage level at low volumes is under the trigger point of the average signal sensing circuit, which means that this particular OEM amp has a high quality output stage section that outputs almost 0V -no hiss- at low volume.
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      04-05-2011, 12:39 AM   #11
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Quote:
Originally Posted by jml View Post
Mastek, one thing to consider if you are paranoid. A lower impedance load will typically be harder for the amplifier to control (damping). You will get a little bit tighter bass at low frequencies (theoretically) with a higher impedance load - so I'd choose the 8ohm units. You may need a larger amp to get the power levels you want.

Also, I would stay away from a class AB amp if you are in a hot climate. 1) You do not want to add any heat to the trunk and kill the OEM amp, which has already shown its colors w/r to heat. and 2) Class D amps are smaller, more efficient, and can themselves run in harsher conditions (because they don't add much heat to their environment).

I can't tell a difference between mono/stereo in my car. The sws subs need to be crossed over at around 100-120Hz, which in a car environment will have little effect on channel separation with the subs 3 feet apart. The OEM units were working in the 200-250Hz mid-bass range, which is a different story.
Wait - what 8ohm units? The SWS-8s come in 2 or 4 ohm
I def want to get a D-Class Amp ...i just dont know which one will give me the best result.
1- SWS-8 (4ohm) in Stereo with an Alpine D-Class 2x150w
2- SWS-8 (2ohm) in Parralel with an Alpine D-Class 1x300
Or what else...?

Wow ... i didnt know the OE underseat subs were set between 200-250hz ...that explains alot. How would I change the crossover output from the OE Amp with just an additional Amp and a LOC from Technic?
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      04-05-2011, 05:01 AM   #12
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Quote:
Originally Posted by mastek View Post
Wait - what 8ohm units? The SWS-8s come in 2 or 4 ohm
I def want to get a D-Class Amp ...i just dont know which one will give me the best result.
1- SWS-8 (4ohm) in Stereo with an Alpine D-Class 2x150w
2- SWS-8 (2ohm) in Series with an Alpine D-Class 1x300
Or what else...?

Wow ... i didnt know the OE underseat subs were set between 200-250hz ...that explains alot. How would I change the crossover output from the OE Amp with just an additional Amp and a LOC from Technic?
Fixed.

4ohms in Stereo (2-channels) = 4ohms total impedance per channel
4ohms in Mono (single channel/Parallel connection) = 2ohms total impedance
4ohms in Mono (single channel/Series connection) = 8ohms total impedance
2ohms in (single channel/Parallel connection) = 1ohm total impedance
2ohms in (single channel/Series connection) = 4ohms total impedance

The amp chosen to drive the SWS-8 is determined by the total impendance to be driven per channel.
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      04-05-2011, 05:15 PM   #13
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I just purchased the SWS-8xi subs and a Rockford Fosgate p300-2 amp. I'm having it installed on Thursday.

The amp is a Class A/B so I'm not sure where it should be mounted: in the trunk compartment or upside down under the rear deck.

Suggestions will be helpful - I'll also report back after the install.
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      04-05-2011, 11:28 PM   #14
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Quote:
Originally Posted by mastek View Post
Wait - what 8ohm units? The SWS-8s come in 2 or 4 ohm
I def want to get a D-Class Amp ...i just dont know which one will give me the best result.
1- SWS-8 (4ohm) in Stereo with an Alpine D-Class 2x150w
2- SWS-8 (2ohm) in Parralel with an Alpine D-Class 1x300
Or what else...?

Wow ... i didnt know the OE underseat subs were set between 200-250hz ...that explains alot. How would I change the crossover output from the OE Amp with just an additional Amp and a LOC from Technic?
I'd go stereo on two 4ohm loads(my bad on the 8ohm comment)

Here is trace speaker level output of the subs and a mic'd RTA of the system with no subs.
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      04-06-2011, 02:45 AM   #15
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What I want to know is how do you even think about selling off a MC431 for a PDX
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      04-06-2011, 08:48 AM   #16
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Quote:
Originally Posted by jml View Post
I'd go stereo on two 4ohm loads(my bad on the 8ohm comment)

Here is trace speaker level output of the subs and a mic'd RTA of the system with no subs.
i assume the green line is just the subs?
well, so much for everyone that said the SWS8 don't go below 30hz
i knew it all along, glad i was using the high pass on the subs at 20hz (lowest possible on MS-8)

what crossover points were you using?
i'd guess 120hz for the subs? and 200hz for the mids?
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      04-06-2011, 10:42 AM   #17
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Quote:
Originally Posted by kmarei View Post
well, so much for everyone that said the SWS8 don't go below 30hz
A lot of that is probably just due to cabin gain.
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      04-07-2011, 12:59 AM   #18
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Quote:
Originally Posted by 808MGuy View Post
What I want to know is how do you even think about selling off a MC431 for a PDX
Lol - i know right

I just dont use it - its sitting there and deserves someone who will love and care for it.
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      04-07-2011, 02:16 AM   #19
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Quote:
Originally Posted by mastek View Post
Lol - i know right

I just dont use it - its sitting there and deserves someone who will love and care for it.
If I could figure out where to put it, I'd buy it in a heartbeat. Always wanted to experiment with one.
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      04-07-2011, 08:50 PM   #20
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Quote:
Originally Posted by kmarei View Post
i assume the green line is just the subs?
well, so much for everyone that said the SWS8 don't go below 30hz
i knew it all along, glad i was using the high pass on the subs at 20hz (lowest possible on MS-8)

what crossover points were you using?
i'd guess 120hz for the subs? and 200hz for the mids?
The green trace is the signal directly from the sub output on the amp. It reflects the factory crossover point. The blue trace is live from an RTA without the sub present.



The blue trace in the next pic is with the sub included in the RTA.
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      11-15-2012, 09:30 AM   #21
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bump to see if you can run the earthquakes off the stock hifi amp,just switching out the underseat subs.

also,which ones for the stock amp,the 8x or the 8xi?
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      11-24-2012, 07:41 PM   #22
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Quote:
Originally Posted by robbiedawg View Post
bump to see if you can run the earthquakes off the stock hifi amp,just switching out the underseat subs.

also,which ones for the stock amp,the 8x or the 8xi?
me too
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