Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help




Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Car Audio and Multimedia

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 07-29-2002, 08:53 PM
scrapdog045
Guest
 
Posts: n/a
Exclamation Please Help!!!!!!!!!!!!!!

i have a ma audio amp that at a single ohm can max out at 1800 watts but im not sure if i can hook up a either a 12" or 13.5"jlw7 or neither because they are 3 ohms not sure if my amp could power them please help
Reply With Quote
  #2  
Old 07-30-2002, 09:15 AM
Registered User
 
Join Date: Jul 2002
Location: Severna Park, MD AND Davidson, NC (School)
Posts: 94
Are you sure you have that figure right? 3 ohm speakers? I've never heard of such a thing, I just know that you can wire speakers together in such a way as to actually get a total 3 ohm load.

First though, even though your amp could push that much power, you don't want to drive it at 1 ohm, even if it is stable at that resistance, which I would bet it isn't.

If you did drive it at 1 ohm, the amp would get so hot that I can't even begin to describe it.

Call the manufacturers of your speakers, and find out what their actual resistance is (I can almost guarantee its not 3 ohms) and then check to see if your amp is 2 ohm stable. Then wire your speakers in according to their resistances (if 4 ohms, which is more than likely) in parallel to deliver a 2 ohm load to the amp.

Where in maryland do you live, and how much experience do you have with speakers and amps?

Jordan
Reply With Quote
  #3  
Old 07-30-2002, 09:50 AM
scrapdog045
Guest
 
Posts: n/a
not much at all just gettin into it but if i went with more ohms wouldnt my max power be lower
Reply With Quote
  #4  
Old 07-30-2002, 10:25 AM
Registered User
 
Join Date: Jul 2002
Location: Severna Park, MD AND Davidson, NC (School)
Posts: 94
That's a common misperception. Yes, it will punch harder with a lower resistance, but to find an amp that is ACTUALLY stable at 1 ohm is almost impossible. It heats up so much that it will cook the amp. Home stereo gear that could drive at 1 ohm will cost at least 5 digits, probably more.

Besides, you are talking about your amp running at around 1,000 watts at 2 ohms if it claims to be able to output 1800 at 1 ohm. At that kind of power, you are looking at having to replace your alternator AND throw in a capacitor to store the power for it. What model amp is it, and what types of speakers exactly are you looking at installing? If you give me specifics, I can answer your question better.

And where in maryland do you live? I live in Annapolis, just an item of curiousity.
Reply With Quote
  #5  
Old 07-30-2002, 11:53 AM
aiznpride
Guest
 
Posts: n/a
from my experience, MA audio over rates their amps. if you want to push that w7, i'd look into a class d monoblock amp like the MTX 81000D.
I'm running 2 kicker 12L7's with an alpine 1507 amp. the bass in this setup is amazing.
-j
Reply With Quote
  #6  
Old 07-30-2002, 11:53 AM
scrapdog045
Guest
 
Posts: n/a
i live in parkville, which is in baltimore county
my amp is a ma audio model SY7011DX

rms power @14.4v dc
1 x 750W @ 4 Ohm
1 x 100W @ 2 Ohm
1 x 1500W @ 1 Ohm

rms power @17v dc
1 x 1000w @ 4 ohm
1 x 1500w @ 2 ohm
1 x 1800w @ 1 ohm
web page i found information on is
http://www.maaudio.com/productcatalog.cfm?class=233

My subwoofer i want to get is either a
12"jlw7 or 13"jlw7

rms 750W rms 1000w
max 1500w max 2000w
web page found info on is
http://www.jlaudio.com/subwoofers/RP_Chart.html
Reply With Quote
  #7  
Old 07-30-2002, 11:56 AM
Ashman's Avatar
Registered User
 
Join Date: Sep 2000
Location: Sherman Oaks, CA
Posts: 4,748
I have seen amps that were supposedly stable at 2 ohms cook under load. So Any amp that claims 1800 watts, may well hit 1800 watts a 1 ohm, then fry within a few minutes.

I never take an amp manufactueres claims to be 100% true.

I would wire it as stated. If you have one woofer, bridge the amp mono, and hook it up to the speaker. If the speaker has dual voice coils, hook it up to both, and let it do its thing.

Thats my opinion, and thats what I would do if it were me.

You should also consider a cap to store power, and then see about the alternator if it is a problem.

Alon
__________________
'92 300CE - Sold
2004 C240 - C7 Wheels - Android Radio
2015 ML350 - P1, Pano, Ash poplar wood, Sport Dinamica interior, Running Boards Keyless go.
Reply With Quote
  #8  
Old 07-30-2002, 12:01 PM
Registered User
 
Join Date: Jul 2002
Location: Severna Park, MD AND Davidson, NC (School)
Posts: 94
Christ that thing is a monster.....

I'd be a little skeptical though...I don't know about a product with that much power that lists at 1000 bucks and sells at 350......

I would be very hesitant to run it at 1 ohm if I were you, 2 will give you more than enough power. Are you sure about the subs being 3 ohms?
Reply With Quote
  #9  
Old 07-30-2002, 12:14 PM
aiznpride
Guest
 
Posts: n/a
from what i understand, the w7's are dual 3ohm vc's. if you have one sub, you'll only be able to run at 6ohms or 1.5 ohms depending on how you wire the VC's (parallel or series).
-j
Reply With Quote
  #10  
Old 07-30-2002, 12:35 PM
scrapdog045
Guest
 
Posts: n/a
so could i run the 12jlw7 to it or not and could the amp handle it nicely
Reply With Quote
  #11  
Old 07-30-2002, 12:39 PM
aiznpride
Guest
 
Posts: n/a
i say you could but u'r amp will hot really fast. if you do decide to go with the 12w7's, try wiring the VC's in series then hook it up to u'r amp. it might be enough bass for you. then wire the VC's in parallel. my friend is running 1 10w7 wired in series (6ohm) and it still pounds pretty hard.
-j
Reply With Quote
  #12  
Old 07-30-2002, 12:55 PM
scrapdog045
Guest
 
Posts: n/a
so should i get another amp and cross and how much more power do u think i need to run a 12jlw7
Reply With Quote
  #13  
Old 07-30-2002, 01:42 PM
aiznpride
Guest
 
Posts: n/a
i don't understand your question. i thin kyou can run the sub with the amp you have. if you don't have the amp, i would look into the monoblock amps i was talking about earlier.
just out of curiosity, why are you trying to run the w7 (one of the higher end subs) with an MA audio (not too high end)? no offense of course. you are free to do whatever. i just htink the 2 does not pair up so good.
-j
Reply With Quote
  #14  
Old 07-30-2002, 02:03 PM
Registered User
 
Join Date: Jul 2002
Location: Severna Park, MD AND Davidson, NC (School)
Posts: 94
In terms of power, you might be going a bit overboard looking at 1,000 watt amps unless you are trying to compete.

I drive my 12" Madisound DVC sub at 100w/channel, and it plays pretty loud. You'd be better off spending more money on a high quality 400w amp than on a high-distortion 1,000 watt amp. That way you also wouldn't fry your alternator trying to suck that much power off the battery.
Reply With Quote
  #15  
Old 07-30-2002, 02:08 PM
Ashman's Avatar
Registered User
 
Join Date: Sep 2000
Location: Sherman Oaks, CA
Posts: 4,748
I run a 450W 2 channel amp bridged mono. It hits an 8 ohm fosgate 10" woofer. Ported in, the bass is nice. If I wanted deeper or louder. I'd step up to a 12.

I like running the 8 ohm woofer. it hits nice and sounds clean.

The amp I have is rated max power at 14 volts, so I assume that under normal conditions, its probably hitting 250-300w

More than enough for me.

Alon
__________________
'92 300CE - Sold
2004 C240 - C7 Wheels - Android Radio
2015 ML350 - P1, Pano, Ash poplar wood, Sport Dinamica interior, Running Boards Keyless go.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 11:09 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page