20 Most Recent Alpine MRP-M650 Car Audio Amplifier Questions & Answers


There are a lot of things that could cause this issue ...
1. Your amp requires more power than it gets when you start your car, and needs to charge up before it can work. If this is the case, you should be able to give your stereo about 5 minutes to warm up at low volume and it should come on. This happens a lot with amps with built-in capacitors (capacitors give you stunning, instant kick when working, but require a bunch of power to initialize). If you wire a bypass switch for the power to your amp and bass components, you can turn it on separate from the rest of the car and allow it to charge before you start your car (just be careful to turn it off when you are going to be away from your car for a while since this will allow your system to drain your battery).
2. Your amp might be set incorrectly for handling the system you are running. If your Ohms do not match up exactly (8 ohm speakers with a 4 ohm amp -- it's the "Impedance rating") then the system should not work at all, or should burn out the amp ... but with a jury-rigged system it can work. If this is the case, I recommend getting a new amp that matches your speakers.
3. Depending on the amp, there might be a volume-based cutoff that is working improperly. Turn on the car with the stereo at low volume. While the speakers are still not working, check to make sure that the amp has power, and seems to be functioning correctly. If everything seems like it's on the up and up, but the speakers are not working, try changing the volume-filter options on your amp.
4. I put this last because it seems like you know what you are doing with the system setup, but it is possible that you have a bad connection between the speakers and the amp, or between the stereo and the amp. There could be a loose connection somewhere (either inside the amp, between the amp and the speakers at the jack, or between the stereo and the amp at the jack). If this were the case, everything would look perfect from a visual inspection, but there could be a tiny space, or corrosion in a connection. Turning the stereo up to a high volume could then bridge this short circuit, and the electric force could magnetize the connection shut, allowing you to then turn the stereo down with the working connection. The best-case scenario here would be an external wiring issue, where you can clean any corrosion off the connections with an eraser, and reconnect everything tightly fixing the problem. The worst case would be a short WITHIN the amp, which would have to be repaired by someone with a lot of time and a circuit tester -- in which case you might be better off trading the amp in for a new one.

Alpine MRP-M650... | Answered on Sep 26, 2012


50 watts RMS x 4 at 4 ohms (75 watts RMS x 4 at 2 ohms)
150 watts RMS x 2 in bridged mode (4-ohm stable in bridged mode)

Alpine MRP-M650... | Answered on Jul 08, 2012


Check your speakers and speaker wires to make sure you have no shorts or grounds. Not knowing what vehicle you are putting the amp in, there is also a possibility that there may be a stock amp in the vehicle. If this is the case, you may have to rewire the speakers and bypass the stock amp.

Alpine MRP-M650... | Answered on Feb 28, 2012


sounds like a short. did you check the amp fuse and the fuse on the power wire (under the hood) make sure there are no wires touching. most common is the wires to the sub touching on the amp. let me knwo if that helped

Alpine MRP-M650... | Answered on May 17, 2011


It sounds like it may be going into a protect mode. You may be overloading the amp. You might want to go higher impedance and take it easy on the amp. The internal power supply MAY be collapsing under the load.

Don't believe all the numbers that manufacturers put out... we call that "Specsmanship"... in other words INFLATED numbers so you buy ours instead of theirs.

Alpine MRP-M650... | Answered on Jan 15, 2011


no it could one 12 but no 2 and def not a 15 when mach speakers to a amp you want to mach up the rms power you want to amp to put out enough to power bolth speakers so like 2 500 watt rms you would want a 1000 watt rms amp

Alpine MRP-M650... | Answered on Apr 01, 2010


bad amp or bad speaker wire ground

Alpine MRP-M650... | Answered on Mar 05, 2010


if you changed the both fuses you mean the amp fuse and the battery?
remember there is a fuse right next to the battery and i believe 2 at the amp.

Alpine MRP-M650... | Answered on Jan 02, 2010


it sounds like you havnt got the memory live conected on your hea duit or it is conected to an ignition live this is no good it needs to be conected to a permenent live to ensure the memory has power at all ties of it coulb be that the amp needs adjusting for low volume use
to set up a sub you turn up the volume to the required level then adjust the amp acordingly hope this helps ben

Alpine MRP-M650... | Answered on Oct 12, 2009


Sounds like the amps needing more current available to it-You should have 4 gauge power coming off the battery going into a distribution block from there a 4 gauge to a 1 farad capacitor off the block -4 gauge to the ground for the capacitor -and two + leads from the block to your amps-you would do well with 6 gauge there.- That is to ensure that you have plenty of power on tap when needed and not trying to draw it off your charging system on heavy current demands.Make sure that your grounds are well placed and solidly connected. As for putting 600+watts on a pair of 8z......i hope that they are the CVR or the L5 / L7 series to take that much power,I've seen it done and the ones i heard sounded badass(L7 series)-but that was at the stereo shop so they had they stuff on HITTN status up in there. If your running the "cvr" or the "comp" series you might be throwing too much power on them -might want to step up your subs to a set of 12s just to get more air moving in there- good luck

Alpine MRP-M650... | Answered on May 28, 2009


USE A HI TO LOW CONVERTER A GOOD ONE BUT ALSO MAKE SURE WHAT KIND OF FACTORY SYSTEM IS THIS BEING HOOKED UP TO BECAUSE IF THERE IS A FACTORY AMP GET THE SIGNAL BEFORE THE OUTPUT

Alpine MRP-M650... | Answered on Dec 28, 2008


The amplifier may be overloaded, check to see if it can handle 4 OHM loads and 2 OHM loads. if it turns off at high volume the amp may be overloaded. if so try a 8 OHM load. if it still turns off it may be an internal problem.

Alpine MRP-M650... | Answered on Dec 28, 2008


Hello Willb2396,

Actually you answered your own question in your paragraph. I draw your attention to your statement of:
"It will work for as long as I'm driving I will park my car, and when I turn it back on every thing will be working just fine and, then a couple minutes later, amp cuts out and won't hit for a couple hours or a couple days.... I have checked the sub multiple times and I don't see it being the sub or the amp"

You are correct it is neither the Sub nor the Amp. The problem is either your voltage regulator or your alternator. one and or the other is going bad.

Here is some advice check your ground wires, the buy a dual alternator kit, it contains the parts you will need to add an additional alternator to your car. This will provide the power you need.

I hope this helps,

Thank you,

Shuttle83

Alpine MRP-M650... | Answered on Nov 14, 2008


as far as it staying on it may have been wired to your hot unstead of your remote on your radio

when it runs wide open it gets hot
how are your gains

I have an alpine and I just hooked up jl 12 w3s and it kinda j did what yours did
it played.. hit hard then no subs.. my mids and highs platyed, but until I would turn off the car and restart the radio the subs immediately came on and the subs are only connected to this aplpine mrp m 650 amp

what speakers and what ohm did they wire it too?

i think my problem was I was overloading my amp feeding it a 2 ohm load or a one ohm load and it was shutting down my subs.. protectection I suppose?


Alpine MRP-M650... | Answered on Jun 19, 2008


try a 60 amp fuses if it doesnt blow when you crank it up it safer lest chance to frying something 100 amp is lots of juice

Alpine MRP-M650... | Answered on Jan 18, 2008


Check voltages at the main power lead to/at the amp and also
at the sense wire which switches it on when the radio is on.
Might be the wiring is too thin and is switches off when current is drawn bigger than that needed to light up the light?
That or the switching power supply inside the amp is unstable/dead.

Alpine MRP-M650... | Answered on Jan 13, 2008

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