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Old 02-19-2004, 05:17 AM
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Rogue, I have a 2000 SS and have a stereo problem. I hear you are the one I need to talk to. I have been to both Circuit City and Best Buy and no one seems to have an answer for me.

I added an amp and single 10" sub to my car with a line-out converter to my stock deck/monsoon system. It sounded okay but not like it should have and I really wanted a sub volume control. So I added an Alpine 7811 deck which has a 4v. sub preout. The sub hits twice as hard easily but now the rest of the speakers sound crappy. First, I am getting amp/rpm whine through the deck. Second, the speakers crackle now. They don't crackle loud, you can only hear it when the car is turned off and the volume is down or at low levels. Third, the front speakers and left rear-hatch speaker barely plays any volume. Only the right rear-hatch speaker plays at normal volume. The sail-subs sound fine I guess.

A few of my friend's say they have added decks to their monsoon system and it worked fine. After reading a few of your posts I think mine should as well. First, let me see if I have this right: The front tweeters and rear 4" speakers play off of the deck power at 4ohms. The front mids and sail-subs are powered off the monsoon amp at 2ohms. Is this correct? If so, my front tweets and rear 4" should sound great with 50watts now and my subs and front mids should sound the same. If this is right, whats my problem?

As far as how to correct this problem, all I can think of is this:
-Install new coax speakers in the front and rear-sails. NO more rear 4" speakers.
-Turn off the monsoon amp and run new wires straight to new speakers from the deck using the 50watts x 4 supplied from the deck.

Only problem with this is that my girlfriend has this set-up in her firebird which only had a basic four speaker set-up and I don't think it sounds that good. The rear speaker highs are too 'in your face.' I like the idea of the subs in the sail panels and the 4" speakers in the hatch. It keeps the highs away from your ear but still there.
I guess I could get a component set for the rear and put the tweet in the 4" area but I am afraid that 50watts wouldn't be enough to support a component set.

What should I do? Best Buy wanted me to use the deck to power the rear speakers and replace the front and rear subs with new speakers and add a 4-ch. amp for them. That sounds good too but $$$$. Any help would be greatly appreciated.
Old 02-19-2004, 05:43 PM
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IMHO you may have killed either the speakers or the Monsoon amp... Either way the internal Amp on that Alpine Deck is better than the Monsoon amp... I would pull the monsoon amp and run new wiring and speakers to the front and the rear sail panels... Cut off the back hatch speakers you dont need em, and theres no need for the sail panel subs as you have an amp and a subwoffer... that will sound a LOT better....

ALSO check your connections for that whine, its possible you have something loose. thats where I'd start... You dont nessicarily need to add an amp to run the interior speakers, the internal alpine amp will do fine, an external amp would be better if you have the cash. DO NOT power a component set witht hat deck it will be way underpowered... You can always just fade the deck forward to shift the sound forward so the rear sail speakers are just filler....
Old 02-24-2004, 02:05 AM
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Thanks for the reply Rogue. Any suggestions on which speakers I should use? I know your fond of Infinity and so am I. It would be cool to keep the entire car Alpine but I really could give a **** less if it sounds good. So what are the best speakers to get if I plan on running it off of the 7811? It puts out MOSFET 50watts.
Also…
I have an Alpine 7811 Deck, Alpine MRV-T757 V12 amp and a 10" Rockford Fosgate HE2 sub. The sub sounds OK but I am not giving it very much power. The amp is rated to run at 2ohms in stereo and 4ohms bridged. The sub is a dual 4ohm sub so I am running it in parallel at 2ohms on one channel of the amp. I was thinking of switching to an Alpine Type-R dual 2ohm sub so I could take advantage of the amp and bridge the amp to the sub. Everyone tells me they are great subs or at least better than a RF HE2 anyways. Do you agree? The funny thing is… this amp is rated at only 750watts MAX! The measured spec’s for the amp is an actual 109watts RMS on a 4ohm load at 12V. How much wattage would it reach at 14.4V when the car is running? Lets say it hit a whopping 130watts, that nothing! But a guy I know says he was running the exact same amp on (2) 15” Type R’s and it pushed them hard!! He says it’s close to 400 or 600 watts RMS bridged! I forget which one, but still, how is that?
Thanks.
Old 02-24-2004, 07:02 AM
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Originally Posted by SStolen
Thanks for the reply Rogue. Any suggestions on which speakers I should use? I know your fond of Infinity and so am I. It would be cool to keep the entire car Alpine but I really could give a **** less if it sounds good. So what are the best speakers to get if I plan on running it off of the 7811? It puts out MOSFET 50watts.
Also…
I have an Alpine 7811 Deck, Alpine MRV-T757 V12 amp and a 10" Rockford Fosgate HE2 sub. The sub sounds OK but I am not giving it very much power. The amp is rated to run at 2ohms in stereo and 4ohms bridged. The sub is a dual 4ohm sub so I am running it in parallel at 2ohms on one channel of the amp. I was thinking of switching to an Alpine Type-R dual 2ohm sub so I could take advantage of the amp and bridge the amp to the sub. Everyone tells me they are great subs or at least better than a RF HE2 anyways. Do you agree? The funny thing is… this amp is rated at only 750watts MAX! The measured spec’s for the amp is an actual 109watts RMS on a 4ohm load at 12V. How much wattage would it reach at 14.4V when the car is running? Lets say it hit a whopping 130watts, that nothing! But a guy I know says he was running the exact same amp on (2) 15” Type R’s and it pushed them hard!! He says it’s close to 400 or 600 watts RMS bridged! I forget which one, but still, how is that?
Thanks.

Well for speakers, ALpines or Infinity would boh be good on deck power.. ou really need to listen to some in a shop to decide...

As for the Amp, DO NOT run a dual 2 ohm sub in parallel to the amp. Then its a 1 ohm load, and that amp isnt 1 ohm stable. If you run the amp as a 2 channel then year its about 109 watts per channel (thats actually quite a bit), To get that kind of continuous power like your friend says the amp has to be bridged and run parallel to a dual 4 ohm load (2 ohms). Bridging brings the power up quite a bit. IIRC that amp puts about 600 RMS out bridged.
Old 02-24-2004, 07:13 PM
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I'm a little confused. The amp is rated at 4ohms bridged (218w x 1 @4ohms). I am going to run a dual 2ohm subwoofer in series for a total 2ohm load. I already have a dual 4ohm sub, that is the problem. The amp is 2ohm stereo so I am only running one side of the amp. I am not even using the other channel. Maybe I am wrong. If the amp is rated at 2ohms stereo but I only use one side, does that change anything? I didn't think it would. The amp doesn't know any better.
Old 02-24-2004, 09:12 PM
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Originally Posted by SStolen
I'm a little confused. The amp is rated at 4ohms bridged (218w x 1 @4ohms). I am going to run a dual 2ohm subwoofer in series for a total 2ohm load. I already have a dual 4ohm sub, that is the problem. The amp is 2ohm stereo so I am only running one side of the amp. I am not even using the other channel. Maybe I am wrong. If the amp is rated at 2ohms stereo but I only use one side, does that change anything? I didn't think it would. The amp doesn't know any better.
Yeah youre only using 1/2 of your amps power. Hook the voice coils up in parallel and bridge the 2 channels of the amp as it shows on the ousides of the amp. IIRC you'll get about 600 RMS out of it.

Where you missed it is that the amp can run 2 ohm stereo if you run 2 ohm speakers off each channel. Thats not the only way it does run. If you put a 4 ohm speaker on each channel the amp runs at 4 ohm stereo at lower power. But you can bridge the amp and hit it with a 2 ohm load and double your power... if youre looking to run 1 speaker. If you were running 2 subs I would wire both speakers VC's in parallel to eachother and wire both into the amp in series.
Old 02-25-2004, 07:43 PM
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I messed up man. I dont mean to beat a dead horse. Last time. Here are actual ratings of amp.

Alpine MRV-T757:
110x2@2ohms
220x1@4ohms

I meant I wanted to run a dual 2 ohm subwoofer in series which would be a total of 4ohms, obviously NOT a total of 2ohms. I wanted to do this because the amp is rated to be bridged at 4 ohms at 220watts RMS. Are you telling me it is okay to run the amp bridged with the sub that I have which is 2ohms total? Technically that would be around 440Watts RMS from dropping the ohm load in half which should double the power, right? But will the amp handle that? If it could, wouldn't Alpine rate it that way to sell it better?
Anyway, I did run the amp 2ohms bridged before I knew it was rated at 4ohms bridged and when I went down to one channel which should have been 110watts rms, it didnt change the sound a bit??? It hit just as hard as when it was bridged... with four times less power..?? Last time I checked, Alpine wasn't a regulated power supply, esspecially not four years ago. What gives? And what does IIRC stand for? Thanks AGAIN. -Mike.
Old 02-25-2004, 10:03 PM
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Originally Posted by SStolen
I messed up man. I dont mean to beat a dead horse. Last time. Here are actual ratings of amp.

Alpine MRV-T757:
110x2@2ohms
220x1@4ohms

I meant I wanted to run a dual 2 ohm subwoofer in series which would be a total of 4ohms, obviously NOT a total of 2ohms. I wanted to do this because the amp is rated to be bridged at 4 ohms at 220watts RMS. Are you telling me it is okay to run the amp bridged with the sub that I have which is 2ohms total? Technically that would be around 440Watts RMS from dropping the ohm load in half which should double the power, right? But will the amp handle that? If it could, wouldn't Alpine rate it that way to sell it better?
Anyway, I did run the amp 2ohms bridged before I knew it was rated at 4ohms bridged and when I went down to one channel which should have been 110watts rms, it didnt change the sound a bit??? It hit just as hard as when it was bridged... with four times less power..?? Last time I checked, Alpine wasn't a regulated power supply, esspecially not four years ago. What gives? And what does IIRC stand for? Thanks AGAIN. -Mike.
IIRC = If I recall correctly. And running that amp at 1 channel at 4 ohms is not giving its full potential. I used to work in an Alpine shop a few years ago and that amp was often used with 2 4 ohm SVC subs that we would hook up in parallel. The amp will put out more than 440 watts RMS, power ratings arent all exact. The amp will definitely handle it, and it turns out I was wrong as I actually found people online running that amp successfully at 1 Ohm . Did you have the voice coils hooked up in parallel, and did you adjust the gains equally?? You will definitely get twice the power + by bridging it and running it at 2 ohms, and it will be fine...

Oh and 1 thing about alpine... they dont sell amps by their power rating, but on reputation, notice its in small print on the box




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