# Just scored 2 Earthquake 40UHCs!



## the_garynator (Jan 3, 2012)

Got ahold of these 2 beauties last night, figured someone on here would appreciate them. Both work flawlessly. one is in excellent condition, the other has a minor cosmetic defect (fins on a corner are bend/scraped a bit) and the switch for the LPF is broken.

Hooked one of them up to my Old school Rockford Punch HX2 8" sub...really makes that thing pound at 600w rms.

I'd link to pictures but apparently I need 5 posts before I can :mean:


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## the_garynator (Jan 3, 2012)

I do have a question...if anyone knows. I pulled the bottom plates off of both, they are internally fused. there are 3 outlets for fuses, but it only has 2 of them with fuses in. 15amp fuses on both sides and the center one is empty. I saw a picture from ampguts of one and it had either a 30amp or a 40amp fuse in the center and a 15 amp on each side.

Any idea what the center one does, maybe allows it to drop to 1ohm or something? Because they both work fine right now, although I have not tested them at 1ohm.


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## the_garynator (Jan 3, 2012)

Just found another picture of the internals of a 40uhc. This one had 3x 30amp fuses.


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## PPI_GUY (Dec 20, 2007)

Is the 40 UHC rated at 600 watts? If so, then maybe your amp requires three 20 amp fuses? If it's rated to make 900 watts then three 30 amp fuses would be needed.


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## ATOMICTECH62 (Jan 24, 2009)

Its old school,high current,inefficient.3x20 for most amps,but maybe 3x25 or 3x30 for this one.
Were these .5 stereo,1ohm mono or even lower?


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## the_garynator (Jan 3, 2012)

ATOMICTECH62 said:


> Its old school,high current,inefficient.3x20 for most amps,but maybe 3x25 or 3x30 for this one.
> Were these .5 stereo,1ohm mono or even lower?


It's rated at:
40w RMS at 4ohm
600w RMS at 2ohm
1200+w RMS at 1ohm
These are at 12ish volts. I've heard they do 1500+ at 1ohm on 14.4v.

And yes, they're rather inefficient, they are power hogs.


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## PPI_GUY (Dec 20, 2007)

Maybe three x 40 amp fuses then? Hard to see that amp making 1200 watts with 90 amps of fusing. Obviously an owners manual would help greatly.


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## upgrayedd (Apr 19, 2011)

Good score.


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## the_garynator (Jan 3, 2012)

So I found out the reason for the weird fuse configuration, etc. Turns out they've been modified so that they are stable (they were notoriously unstable at high output) for music and such.


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## jcorkin (Jan 26, 2012)

alright now you are at 6 posts lets see some pics!


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## the_garynator (Jan 3, 2012)

oh yeah, forgot about that, here you go:


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## the_garynator (Jan 3, 2012)

Here are some better ones too: 
IMG_9835_120127.jpg | Flickr - Photo Sharing!
IMG_9834_120127.jpg | Flickr - Photo Sharing!
IMG_9832_120127.jpg | Flickr - Photo Sharing!
IMG_9820_120127.jpg | Flickr - Photo Sharing!

Here's a video of one of them powering my new DC Audio LVL 5 15"
http://youtu.be/7Akalso7Zp8 (there are other videos of them powering misc other subs on my youtube channel)

Also, both of these are on ebay currently: http://www.diymobileaudio.com/forum...-earthquake-40uhc-golds-sale.html#post1553307


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## jcorkin (Jan 26, 2012)

cool, I've got a power 400tx that is just like those.


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## the_garynator (Jan 3, 2012)

jcorkin said:


> cool, I've got a power 400tx that is just like those.


Cool, is it a gold edition, or a regular one?...you have any pictures?


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## jcorkin (Jan 26, 2012)

it looks like those but with red writing i will get some pics of it tonight when i get off of work and head home.


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## StockA4 (Aug 26, 2011)

I know this thread is ancient, but do any of you happen to have a manual for the 40UHC? 

Thank you.


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## the_garynator (Jan 3, 2012)

StockA4 said:


> I know this thread is ancient, but do any of you happen to have a manual for the 40UHC?
> 
> Thank you.


i don't, but i have done a lot of research into them, what are you trying to figure out?


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## StockA4 (Aug 26, 2011)

I guess I just need to know what size the internal fuses should be. Mine are sitting at 15, 30, and 15.


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## the_garynator (Jan 3, 2012)

StockA4 said:


> I guess I just need to know what size the internal fuses should be. Mine are sitting at 15, 30, and 15.


That sounds about right. The other 40uhcs I've seen have either that configuration or 15, 40, 15. The reason mine have the center one missing is that they are modified.


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## StockA4 (Aug 26, 2011)

Really? I'd like to know what you had done. One last question; have you ever tested your amp (stock) to see if it did at least rated power? We've been finding out recently that some of the old school ratings have become grossly inflated by bad memories, nostalgia, and incorrect testing methods. I'm going to test mine, but it's not going to be for awhile.


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## smgreen20 (Oct 13, 2006)

Wow, back to life this thread goes.....

I recal most of the OS Earthquake amps doing more then rated. Not by much (10% more or so) in reviews I remember reading.


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