Factory Head Unit Power Rating?

I own a 03 Protege Sedan DX and I emailed Mazda about the RMS rating of the factory headunit and they told me it was 25x4. I am thinking this is peak power but they insist its RMS. So my question is if this is true what is the peak power for the headunit. I am looking to just replace the door speakers and rear deck but don't want to spend the money for a aftermarket headunit if the factory can power my speakers good. Because 25x4 is a good RMS power rating just as good as some of those aftermarket cd players.

Thanks

protegerider18 said:

I own a 03 Protege Sedan DX and I emailed Mazda about the RMS rating of the factory headunit and they told me it was 25x4. I am thinking this is peak power but they insist its RMS. So my question is if this is true what is the peak power for the headunit. I am looking to just replace the door speakers and rear deck but don't want to spend the money for a aftermarket headunit if the factory can power my speakers good. Because 25x4 is a good RMS power rating just as good as some of those aftermarket cd players.

Thanks

Click to expand...

Simply put, Only the enginneers know the rms rationg and no one really cares. Mazda Customer Service will only have the 25 x 4 as an aswer for you as it is all they know. The realistc number is under 10 x4 depending on meather used to take the measurement.

Most aftermarket speakers will be fine with the deck powering them. This is so long as you don't push on them once they start distorting. IF you do, you'll blow them. Otherwise, they will last a good long time. IF you are never going to amplify them with a seperate amp, then stick to less expensive coaxles and componenets. Preferably 50 RMS or less. Although thats not a good measuring point as not all manufacturers rate there speakers the same. Some manufacturers rate speakers at 150 watts rms but my amplifier would teir them apart. My speakers are only rated at 60 watts rms but my JL 300/2 (150x2 rms) is a perfect match for them.

I'd go to a store and start listening to some speakers. Keep the budget around $100-$150 or so and you should have a good deal of speakers that sound great, will be decent with the factory deck, and will handle a nice external amp in the future. The JL audio TR's would be my choice, but your ears different so look around.

uhh, hold up. our old, underpowered head unit can blow out really good speakers? If so s***, cuz i was gonna replace the speakers befoe i got the head unit. now youre saying I could kill em if i do. I figured that thy would be really quiet.

Missile_Man said:

uhh, hold up. our old, underpowered head unit can blow out really good speakers? If so s***, cuz i was gonna replace the speakers befoe i got the head unit. now youre saying I could kill em if i do. I figured that thy would be really quiet.

Click to expand...

Yes it can, as can any aftermarket headunit or underpowered amplifer. They all start to creat a clipped wave when you push them past there limits. When this happens the audio signal is no longer like an AC wave and becomes more like a DC wave. When this happens the signal creates alot more heat in the driver. Also, raising the bass or treble past 0 will also distort the signal much earlier and cause distortion and possibly driver failure.

This is for lower fequencies mostly. Higher frequencies don't actualy distort that quick but tweeters are the first to typicly blow. I'd get into this but not many would fallow me on it. If your interested in reading about it I can link you to Rane Electronics website.

You always want to have enough power to achieve your desired without any part of the signal clipping. To do this you need power. Infact, its better to have speakers that are rated lower and a higher powered amplifier.

So long as you pay attention to what your hearing and don't push things once you hear distortion, then everything will be fine. However, the most commonly blown speakers are powered from factory or aftermarket head units.

hmm, so what im starting to understand is that id be actually be better off running a better head and buying new speakers second. Im on a fairly low income, its what you get for being 16 and being in high school, s each of my purchaces aregonna be about a month or so apart, and sounds like now im gonna start with the head not speakers. 1sty, I think id be screwed without you. All the mechanical and instalation I can deal with but im not an electrical engineer, yet.

Like I said, both the factory unit and an aftermarket one can both kill speakers. THis is becuase they are not causing the damage, its the chuckle head controlling the volume knob that is. The good news is that the factory speakers are more likely to blow then aftermarket ones with a given source. So if the factory ones are still ok, your ear should be good enough to keep things low enough to be safe.

You shouldn;t be getting a new deck to achive louder volume or different sound. They can do both but not terribly effectively. If you want a different sound, get speakers. If you want it louder, get an amplifier, if you want features then get a new head unit.

well thats the thing, I will be getting Head, speakers and amp, Its just the order that im getting them in. I just cant drop $1300 inside a week or 2, its gonna take me a couple months to get it all. Like I said, a 16 year old only has so much time in wich to make money. This is all I can hope for (birthday)

But won't a aftermarket cd player make aftermarket speakers sound better than factory speakers.

protegerider18 said:

But won't a aftermarket cd player make aftermarket speakers sound better than factory speakers.

Click to expand...

Not unless the factory head had a DSP chip which the protege doesn't. Other then that an aftermarket unit just gives you a bit more power which will correlate to a +3db to a +6db increase and alot more ways to cause distortion.

SQ wise, many factory head units are as good if not better then aftermarket units.

When I had my stock HU, I dropped in some old Kenwood 6909S.(6X9 3-ways). The tweeters and midranges would choke at higher volumes. Once I dropped in my Panasonic HU, the clipping went away, and I could play them a little louder. I beleive this was due to the distortion that the stock HU put out at near maximum volume levels. All amps distort like crazy once you near their max output. The SQ improved slightly. Most ppl wouldn't even notice. Oh, and the stock HU puts out 7watts a channel. Not much, but it did power my power hungry Kenwood's(somewhat). If you got some decent 2-ways, the stock HU would be sufficient. Like 1sty said, get some that are rated around 50watts RMS. Also, if you replace the rear 6X9's, make sure that they will work fine firing into a trunk. My Kenwoods sounded way better boxed. Although, all speakers sound better boxed. Still, it's worth looking into. On a sidde note, I noticed this thread got 100 views! I guess everyone is curious as to the stock power rating. lol