for audio know it alls

for audio know it alls

ok im planning on getting a full alpine system for my car...the alpine type x 6 1/2 components in the front (240W Peak Power - 60W RMS) and the alpine type r 6x9 in the back (200W Peak Power - 50W RMS). now i want to get everything alpine and im looking for a nice amp that will power this speakers but won't blow them.. i have a list of some alpine amps and there specs but don know which one is the right one i need...

mrv-f540 (4/3/2 Channel Power Amp)
200W x 2RMS @ 14.4V | 100W x 4RMS @ 14.4V | 80W x 4 RMS @ 14.4V | 140W x 2RMS @ 12V | 70W x 4RMS @ 12V | 50W x 4 RMS @ 12V

mrv-f340 (4/3/2 Channel Power Amp)
130W x 2RMS @ 14.4V | 65W x 4RMS @ 14.4V | 55W x 4RMS @ 14.4V | 90W x 2RMS @ 12V | 45W x 4RMS @ 12V | 35W x 4RMS @ 12V

mrv-f450 (5/4/3 Channel Power Amp)
120W x 2RMS + 200W x 1 @ 14.4V | 60W x 4RMS + 50W x 4RMS @ 14.4V | 80W x 2RMS + 150W x 1 @ 12V | 40W x 4RMS + 30W x 4RMS @ 12V

mrp-f240 (4/3/2 Channel Power Amp)
100W x 2RMS @ 14.4V | 50W x 4RMS @ 14.4V | 40W x 4RMS @ 14.4V

First of all, you have to know what kind of power your deck is putting out on it's preouts

If it's putting out 12V then you want to look at the @12V numbers, if it's putting out 14.4 then you want to look at the @14.4V numbers.

Second, are you planning on getting a sub? the "mrv-f540 (5/4/3 Channel Power Amp)" for instance is made for speakers + sub, so it's kinda useless otherwise ((note, you have a typo there because you have the model number mrv-f540 twice))

Safety-wise, it's probably best to go with an amp that gives 50W RMS (because that's the lowest RMS that your speakers will take) @ the voltage your deck puts out. At least, that's what would make sense to me.

So, if your deck puts out 12V, then mrv-f450 (4/3/2)
otherwise, mrp-240

My question is, though, why bother with an amp? If you put the money you'd spend on an amp on a higher end deck than what you'd buy otherwise, you can get a deck that puts out 50w x 4 RMS through it's own MOSFETs...you'll probly get more nice features too....

Don't worry too much about your deck outputs. Most Alpines are 4 volts I believe, but that's what the gain setting on the amp is for.

You want to look at the power output of the amp at 14.4 volts into 4 ohms. When your engine is not running, the amplifier will get about 12.5 volts from the battery. When the engine is running and the alternator turns, the electrical system voltage is closer to 14.4 volts.

The MRV-F540 is rated at 80 W RMS per channel (4 channels) into 4 ohms at 14.4 volts. That's too much for the speakers you plan to use.

The MRV-F340 is rated at 55 W RMS per channel (4 channels) into 4 ohms at 14.4 volts. This one would be a good choice.

The MRV-F240 is rated at 40 W RMS per channel (4 channels) into 4 ohms at 14.4 volts. This one is a safer choice than the 340, but I'd still go with the 340.

The MRV-F450 is rated at 50 W RMS per channel (4 channels) into 4 ohms at 14.4 volts, plus a single channel at 200 W RMS. This one would be a good choice if you're planning on adding a sub at some point.

As for decks, they generally don't put out much more than 30 W RMS per channel before the distortion starts to get out of hand. A lot of manufacturers will claim their decks are 50 W RMS per channel, but neglect to tell you that the THD is 20%. Alpine amps are generally 0.08% distortion at their rated power into 4 ohms.

ok thanks for the error spotting...as for my head unit this is what i have

Pioneer DVH-P7000
DVD Player Features:
DVD/Video CD/CD Player
DVD-R/RW & CD-R/RW Compatible
96kHz/24-bit D/A Converter (DVD)
Optical Digital Output for DEQ-P7000 Multi-Channel Audio Processor (Dolby Digital/DTS/Dolby Pro Logic)
Composite Video Output (Front + Rear)
RCA Audio Output (Rear)
Dual Zone (Two Different Sources)
Operation for Front & Rear
Receiver Features:
Organic EL Display (128 x 33 pixels)
MOSFET50 (50W x 4 - Channel High Power)
Supertuner­III?
XM Ready
EEQ Performance Chip with Parametric EQ
SFEQ Performance Chip with Independent Front/Rear Bass & Treble
Two-Way Crossover (HPF & LPF)
Hi-Volt RCA Preouts x2 pair (4V - Front & Rear or Subwoofer)
IP-Bus System Control (XM Satellite Radio, TV Tuner, DEQ-P7000, MCD or Auxiliary Unit Control)
Remote Control
Detachable Face Security

as for subs i dont really plan on putting subs in the car... and as for having a good head unit instead of buying an amp...my head unit is great but the person im buying the speakers from said that most people blow their speakers from under powering them.. which to me didnt make sense...how can you blow speakers with low power? so he said to have the power level near what its suppose to be....as for amping whats the differece say like the stats for the components in the front " (240W Peak Power - 60W RMS) " does that mean i have to have an amp with minium power of 60W going to the speakers just as long i dont put an amp more then 240W?

Them Alpine comps. Type X will have no problem taking 80wRMS. :wink:
I'll go with the F540 if you got the money, if not the F340 would do the job too.

If you go with the F540, just dont set the gain the the rear too high or your rear speaker will clip and the front comps. will still ask for more power.

Speaker can be blown buy underpowering because when the speakers are underpowered, and when you turn it up, you will expeirance clipping. Clipping kinda sounds like your speakers are blown because you will hear some nasty sound out of them. The head unit is rated 22wRMS but in reality it can do about 13wRMS. When you system is asking for 60wRMS and when you turn it up the deck will give bad nasty signal to your speakers.

When your speakers says 60wRMS and 200wPeak, it means that it is able to handle 60w continualty without a problem. But since not all music is flat, sometimes when bass hit, it sends out more power. So your speakers is able tohandle up to 200w at single burst.
Really dont worry too much about peak power, they just have it there for advertisment and bragging rights. If you are still new the the whole audio thing, look for RMS rating comparted to Peak rating. The only exceptiong that I've ever seen is the alpine componests. For some reason the lower line type S has more RMS than the type R.

i think it would be worth it to add a sub for a complete system. one of hte lower end alpine subs in a sealed box isnt going to cost you too much and sounds alot better.

Depends entirely on the music you listen to. Tchaikovsky's 1812 will take 'em out no problem.

Super's right, all that really matters is RMS power. RMS power though is not so much a function of the amplifier, but of the music you listen to.

Peak power is a measure of the power output by the amplifier when it is at its peak voltage output. It's not really a measurement of peak power but a measurement of intantaneous maximum power. For RMS ratings, most manufacturers will use a sine wave. RMS is the root mean squared value of the power over time. If you take the sqare root of the integral (for those that know calculus) of the square of the voltage, you get a value of 0.707 (1 divided by the square root of 2) as the RMS value of a sine wave compared to its peak power. Power is proportional to voltage squared, so the RMS power of a sine wave is 0.5 the peak power.

Music is never a sine wave though. Try listening to one and you'll get annoyed very quickly. With most electronic music, the RMS value is generally about 20% of the peak power. If you have an amplifier rated at 100 W RMS (sime wave) and 200 W peak, you'll probably get about 40 W RMS out of it when listening to most music before the amplifier starts to clip.

Jazz and Classical both generally have much higher RMS values as compared to the peak, so if that's the kind of music you like, be careful about the amplifier you choose.

Clipping is another interesting issue. When you overdrive an amplifier and the output starts to clip, you are asking for more voltage out of the amp than it is capable of delivering. The wave gets a flat top, which means a sudden change in the rate of voltage change at the point of clipping. This sudden change introduces a whole bunch of odd harmonics, generally referred to a total harmonic distortion. There's a method called Fourier Transforms that allow you to calculate the harmonic components, but what happens is you get a bunch of high frequency harmonics that increase the power in the high frequencies so much that the tweeters can't survive the onslaught.

If you want to be safe and not have the hassle of warranty issues, choose an amplifier with an RMS rating at the speaker's RMS rating - a little lower is OK and a little higher is fine, but if you go too far either way, you may blow something eventually.

And avoid Tchaikovsky.

ok so it seems like the mrv-f340 is the best choice.. i went to my local shop and asked them the same question because they now deal with alpines instead of mb quartz and they where telling me that the alpines are actually power hungry speakers.. since they are the place that are going to put in for me they insisted that i get an amp... they said that they would give me a memphis 4 channel amp but didnt tell me the specs on it yet...but he said he would charge me 275$..he said that if the speakers blow cause of his amp then he'll replace everything but if i bring my own amp and stuff blows he is not going to be liable.. lol i think he was trying to scare me into buying his amp

Power hungry speakers? What does that mean? Low efficiency?

What is $275 going to get you? I agree - sounds like he's trying to scare you into buying what he's selling. One thing I've found about car audio in general is that there aren't very many people in the business that really know what they're talking about. They do know a lot , but don't understand much.

ok and as for subs i would get them but i dont like putting all that weight and taking all that space in my trunk...also what really annoys me is the rattling.. i hate it when people have that rattling sound and people blasting their music like its not noticeable... and plus it cost alot also to put some subs in there..

Honestly, I don't like the rattling much either, but subs, if installed well, do make the system.

power hungry speakers....i guess he means it just needs alot of power because i asked if my head unit would be fine to run the speakers that i wanted...for 275$ i think the amp i would be getting some kind memphis... maybe something like:

Memphis 16-MC3004
RMS Power 4 ohm (Watts) 75 x 4
RMS Power 2 ohm (Watts) 115 x 4
THD 4 ohm - 0.03%
Frequency Response +/- 1 dB - 10Hz-50Khz
Dimensions (in.) 6.5 x 2 x 16.4

Does $275 include the install?

no just for the amp they said another $100 for the install and the wires

the rattling does get annoying but just take some time to go through everything that rattles and tighten everything or make it so it doesnt. usualy hte mirror, deck are common ones. i have 2 12"s in my trunk with much trunk room to spare. probably weighs over 100 pounds

stuck in a dilema...is the Alpine setup good? because i was debating betweent that Type X component in the front and Type R in the back with MB Quart RCE 216 6.5" component in the front and MB Quart DKE 169 in the back...i havent heard MB Quart...and i can get the Type X component for the same price as the MB Quart Component....the thing is i know that the RCE is not their best model because they have two levels higher...the premium components...and the their top of the line "Q Series"...and the Type X is the best for Alpine

MB Quart RCE 216
Impedance
4 Ohms
Frequency Response
38-32.000
Sensitivity
2,5W 90dB/1m
Power Range
60-130 Watts
Crossover Frequency
4.200 Hz

MB Quart DKE 169
6"x9" 2-Way Speakers
Power Range: 60 - 140 Watts
Frequency Response: 35 - 32,000 Hz
Sensitivity: 1,8 dB
Crossover Frequency: 4,500 Hz
Impedance: 4 Ohms

this the Premium for the MB Quart
MB Quart PCE 216
Impedance: 4 Ohms
Frequency Response: 38 Hz - 32,000 Hz
Power Range: 60 -130Watts

i dont know anymore info then that...if someone knows anything else about the MB Quart speakers it would be helpful...the PCE is going to run 100$ more but i dont know if its worth it....is their RCE is equal to the Alpine Type X?