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Quick question regarding car stereos and speakers? Answered

Hi, so I was thinking of buying a new stereo (receiver) for my '97 Mitsubishi Mirage DE, along with some speakers (mine are crap). When I go online (such as autozone.com), I run into some confusing descriptions. The receivers are usually rated as 200W for four channels (it'll then say like 50W x 4), whereas some of the speakers say "100 Watts Peak 50". I think I only have two speakers on the interior of the car (driver and passenger). Does this mean I can buy speakers with a higher wattage? I'm guessing the 50W x 4/ 200W over four channels means that it's 200W of power/audio for four interior speakers. Does having less speakers give me a greater allowance for speaker power, or will less speakers put more strain on the ones that I install (200W getting split over two channels instead of four)?

For reference, here is the receiver I'm looking at, along with a pair of speakers I found that fits the "Peak 50":





Best Answer 7 years ago

The channels are separate. If you only use the two main speakers you won't be able to use power from the other 2. So 50 watt speakers should be okay.

The one exception is if the amps are labled "BRIDGEABLE".  That means that you can connect the amps together and effectivably get 100 watts on 2 channels.

So then I should stick with 50W speakers if I get the stereo?

. 50W or higher. Use speakers rated for 1kW if you want to (might be a little bit inefficient at lower volumes, but not too bad).


3 months ago

I have a motorcycle with a Kenwood 450 watt amp. Bluetooth 4 channel. I have speaker lids for 2/ 6.5" speakers. What is my best speaker set up.

Ok, I know this is an old question and thread, however, I just sat here in utter disbelief at what I was reading. ALL of this is the most horrible, ridiculous and patently false information being given. Speakers that are of a lower power than your amp will cause your amp to start clipping. Meaning it will clip off the top parts of each sound wave causing it to send a square wave to your speakers. That is the best recipe for disaster and a perfect way to ensure that you blow your speakers in very short order and overheat and fry your amp. You want an amp with an RMS power output, per channel, that is at least 50% greater than the speaker's rated RMS power. PERIOD. Or don't. It's your money and your speakers. If you follow that rule, then you can turn up your volume to where you begin to hear distortion and back off just enough to clear it back up. That will be you're speaker's maximum capacity.

CORRECTION: Speakers of a higher power, or equal to, that of your amp's output.

I have a Sony MHC-GNZ888D Mini Hifi system which is not working any more. But the speakers are in working condition, so I want to know which amplifier I can use to make use of the speakers. The speaker reading as per wattage (160W×2 and 50W×3). Can anyone guide me in selecting a amplifier for making use of the speakers.


Ive just started reading this thread as I'm interested AND dumb when it comes to car stereos and their optimum setups. Gauging from what a few have said I might be going about things all wrong in my Commodore. I've just got a 30 x 4 Kenwood 'deck' (yes.. tape deck) and in the doors I've got 150w speakers... Is this an error on my part..?

Just to clarify something:
There's nothing like 'underpowering' a speaker.

If you put your volume dial at near to zero, even with a 1000W amp, you'll be outputting very little power. Even if the speakers are rated 1000W each, they will play just fine with 1Watt (though not very loud).

Basically changing volume changes power output.
'Iminthebathroom' is correct in saying that if your radio is rated 4x50W, your optimal speakers would be 50W speakers.

Plugging in 45W speakers will sound amazing at max volume, because they will extend beyond their rated reach. Speakers may sound way more punchy when you overdrive them!
But on the other hand,you will be reducing their lifetime significantly.

Overdriving speakers by as much as 10% (5Watts on a 50Watt speaker), will cause speaker life decrease, like speaker tearing,or tweeter rattling; as well as possibly wear out some dampers that keep doors and other material in your car from rattling.
Overdriving speakers by 10% could reduce their life upto a few years of operation only!
The curve 'operation hours per watt' goes pretty steep, the closer you get to running speakers at their maximum rated power; eg: people who run their paper cone 50W speakers at 1W constantly might be able to use them 32 years without problems.

People using those same speakers at 32W constantly might reduce it to 4 year operation. Running them at 64 watt, perhaps results in only 6 months of operation. Another thing to keep in mind is that many audio amps can be overdriven. Eventhough they are rated 4x50W, they could potentially give small bursts of 100W RMS (by eg: short circuiting certain internals, or connecting a very loud headphones signal into the line in).
Different from peak power, these signals could be a succession of peak power bursts before the limiter kicks in to protect the speaker,played again as soon as the limiter shuts down. For this reason manufacturers recommend to install 75W speakers into a car with rated X x 50W radio.

But if you never are going to play back at maximum volume,you might as well find speakers between 45 and 60W,to get a better efficiency.

I can also say that many car radio's suck, and that sometimes the stock speakers might sound surprisingly better when switching the stock radio!

i just had a 1000w amp with two 1600w 12" subs into my truck ( jeep cherokee) .
now i cant really hear the door speakers . they werent loud anyway but now its worse. i have a 50w by 4 stereo and like to know what watts i should use to get good sound and loud from my highs .

Regardless of which you choose, and this will help you later on as well: Always make sure your receivers capabilities exceed your speakers maximum, and you will always be happy. If you buy 300w speakers and your car stereo can only output 50w per channel, your sound quality will suck when you turn it up. 20w speakers will sound better, be louder and put less strain on your receiver. This basic rule will apply if you were to add an amp and larger speakers as well. Your amplified source be it 1000w will sound better, be louder an easier on your system if the speakers running off it are slightly less then 1000w. Hope this makes sense, it all a balancing act but if you apply that basic rule it makes thing simpler regardless of the terminology used at the time.

.  Unless audio has changed drastically in the last 15-20 years, you have things backwards. If you overdrive a speaker, you will burn it up; if you underdrive a speaker, well ... it sounds about the same.
.  Push 1W into a 100W speaker and it will still sound pretty good and the difference in volume, compared to using a 1W speaker, will be very little. Push 100W into a 1W speaker and you let the magic smoke out of your drivers.

Haha, True enough! Guess I forgot the one little thing, you want the wattage to be as equal as possible, but you still want the receiver to out pace the speaker, but just by a touch. Yes if you crank it you will make your speakers go poof! this is true, but usually what happens is when the underpowered speakers are turned loud, to compensate for them being underpowered you get a clipping signal. This clipping signal causes greater distortion which will sound horrible and eventually wreck the speakers coil. This clipping signal also has a potential to feedback to the head units internal amp and can damage it. I have seen this happen several times before. If you don't mind the much lower volume out put and your not going to turn it up loud to compensate then no damage will occur, but if you do be warned. Either way I guess you have the potential to damage something, I'd rather it just be the speakers. Please if I'm missing something post back, I'll learn something too!

.  What you are describing is operator error, not bad speakers or amp. You can drive almost any (when it comes to car systems, we can probably scratch the "almost")  audio amp to clipping. If you are willing to listen to music with enough clipping to wipe out your tweeters, you deserve to blow something up.

Yes, you are correct - operator error big time. Not knowing whom I'm talking to though I just like to er one the side of caution. Eventually there are going to be times where the music is going to be turned up, Having the head units power output slightly exceeding the speakers ratings reduces the chances of destroying speakers in addition to the head-unit. Speaker damage like this is prone for larger speakers, especially sub-woofers and straight woofers. The speaker coil is usually what gets damaged, as opposed to a blown speaker which can also include the actual surround. Of course if you crank it past the point of distortion you will indeed blow the speakers in my configuration, just not the head-unit as well. On a side note, I have seen home stereo amps damaged this way, feeding over powered speakers. I am not sure if the damage occurs the same way though as is a slightly different beast all together.

Wait, so then should my speakers have a higher wattage/peak wattage than my channel output? So for example, if my head unit/receiver is putting out 50W by four channels, should both of my speakers be like 60W+?

. 50W or greater.
.  As Re-design points out, the speaker power rating is the maximum power the speaker is designed to handle and does not impact how loud the speakers are at a given input nor how good they sound at less than maximum.
.  Not sure where iminthebathroom is getting his/her info, but it's way off base.

Oh, and try not to get caught with rms ratings. your not participating in any SPL woofer competitions are you? if not not just keep it simple and look for the overall speaker wattage.

Um in my opinion 60w should be fine, but 45 to 50w per channel would be ideal. It would give you the best ratio of sound quality and the ability to turn it up loud with minimal distortion. Bet you when you take out your existing speakers they will be from 5w to no more then 20w, and that would be pushing it. Sometimes I have been impressed by simply installing a new head unit and leaving the stock speakers and been amazed at the sound quality. Just keep in mind the older head units output was probably much less then your new deck. Now if you try and dump 2 channels designed for regular speakers, say your left front and left back into one speaker you are not suddenly going to get 100w of power and you can fry your speakers coil or over time damage your head unit. It would be far better to go with 4 speakers. Most modern decks also have sub & speaker pre-outs. These are usually in the form of RCA jacks, and are designed to be fed into a amplifier. If you like base, this is where you want the amp and sub-woofer. You can run 2 or 4 speakers (usually the front if using 2 speakers) and run your sub-woofer(s) off the amp, through the pre-amp and have great sound and base.

The wattage of the speakers is the MAX that they can handle. NOT the amount of power they need! If you put more power into them then they can handle the WILL burn up. The power rating has NOTHING to do with how much power they need to sound good.

Many car stereo systems ( the professional ones) are used for creating short periods of bass, that's why many ampfiers say 100w RMS ( root mean square ) and a peak such as 300w in relation to the amp this example would vary.
For a car stereo of a moderate size I would go for a 4 x 50w RMS 100w peak amplifier and maybe buy 100w max speakers.
If you want it really loud I would go for a 4 x 100w rms amp. And 200w + max speakers.