Installation question.

yeah but if he keeps the stock speakers in the back, is it really a bad thing if they do happen to blow.
 
It boils down to simply being a choice to fit a situation. The ideal is certainly to amp everything as that will tend to give the listener or installer much more control of the speakers, stage, and imaging. However, when a system is being shopped on a very tight budget, the rear speakers are a great place to ignore and focus money elsewhere.

Worst case, you can always put a small fuse inline with the rear speakers.
 
And if you are using an aftermarket deck (or even the stock HU) you can use your fade control to fade front a little (hence lowering the rears). Setting this stuff up is part of the correct install. Spending $$s on amping the rear is quite pointless, and if your system is setup properly you don't need to do it. I'd rather take the time and save the money. Plus a good aftermarket HU is not putting out bad quality audio that can ruin speakers, its just not putting out as much as a good aftermarket amp.

One of the things I did after dialing in my system is to set it at what I ahd determined as the max volume I should put my HU to with all speakers on. Then I systematically listened to each speaker (front, rear and sub) ON ITS OWN using the same songs I'd used to dial things in with all speakers on.

I actually ended up backing my sub off a notch as it didn't sound so clean when playing alone (by which I mean, with all speakers on, the total sound was limiting my ability to hear each individual speaker's performance.

Now I am doing this with all HU amp for front and rears as my current system just has aftermarket 5.25" speaks in the front and stocks in the rear. I am soon to be upgrading to some comps with the new eD amp I am (eagerly but patiently) awaiting.
 
That is a good point about the money thing. If you are on a tight budget and cant afford to amplify, by all means use the fade control. But if you are going to amplify fronts, you might as well amp them all and have better quality (and cleaner power) all the way around.
A four channel amp is not a whole lot more than a large 2 channel either.And I dont know if you have heard the difference between and amplified system all the way around and an amplified system just in the front, but there is a big difference. Yes you have to tune the system right, but you have to do that with any system, even a stock one. Amplifiing anything is never piontless. you just have to want it.
1 canuck 2, Actually HU power can hurt your speakers, and although inaudible sometimes, even an aftermarke HU will put out distorted power ultimately ruining your speakers over an extended period of time.
1sty, putting a fuse on the speaker will do absolutely nothing unless you are going to put voltage through it.(which you obviously would never do.) If you want to somewhat protect a speaker you need to put on a cap or some people call them a bass blocker.
 
Speakers run off of voltage, granted it's AC, but howelse would one make an electro-magnet move back and fourth thatmuch???

Thatsaid, I don't know your particular obsession with amped rear channels, Sure they're potentially nicer to your speakers, but for one, I've pretty rarely come across speakers blown by HU power that were played nicely. And then there's the matter of who needs rear speakers? woo hoo "fill" I've heared all sortsa amped rear speaker setups, and have had a few, on those that weren't mine, I always faded about as far forward as possible to make things sound decent. On my personal ones, I was pushing only a midrange, and always got toomuch bark out of it. Call me crazy and sound-dumb, but I just don't see the point in spending money on an amp and speakers that do you no good.

As much as a HU will distort and eventually blow speakers over time, so will an amp. It's all about how you use it. Nowthen it Is entirely possible that with rear amped speakers one could more readily hear distortion because everything will be louder. Also I Will buy that if ppl are looking for alot of volume out of their rear speakers that amps are a good thing because turning your HU up another notch is not always the best option.
 
Either way, Welcome to the forums and such, THis is quite an incredible information exchange we've got goingon here, and judging form other audio boards on the web, protege owners are some very with-it cats. You seem to have some knowledge and it's always nice to have more of it around here. There's also alot that can be learned from many of these guys.
 
amplifying all speakers giving you a better quality sound is highly debateable. i tend to not run rear speakers because they don't improve the sound whatsoever in my opinion, i'm going for the most realistic sound possible. and when i go to concerts all the sound is from in front of me. some people will shout about reflections from the back, but this is incorecct also because rear speakers are playing the same exact sound as the front speakers,and they are playing at the same time. a reflected sound off the back of a concert hall sounds nothing like a pair of speakers behind u playing the same image. if i had a 4 channel amp. i'd just bi-amplify my compet speakers up front with more power.


yes aftermarket headunits can blow speakers, just the same as aftermarket amps can, it really has nothing to do with the equipment, it has everything to do with how the system is played. some people like to give an answer to a question in a way that saves the equipment because it's assumed the listener will turn things up to much, i'd prefer to tell the listener the proper way to tune a system and hope they come out more knowledgable. oh and u can put a proper fuse on a speaker, basically the fuse will blow before u damage the speaker, its been done before, not your standard way of doing things, but it is an option. i prefer just to tune it properly.
 
I am with both of you sndsgood and poseur, you have stated (in a better way) my earlier point. If you set your s*** up properly and know what you are doing, amping rear speaks is a waste of money. It does nothing for the audio reproduction, because if you can "hear" your speakers" they are up too loud.

You'd be much better off spending the diff between a 4 and 2 channel amp on a better 2 channel amp and/or better front speaks.

1sty, did you mean resistor instead of fuse? I know you can put a resistor inline to lower the rear speakers somewhat if fade is not available.
 
Okay guys Im not trying to say that it is wrong to amplify just the front speakers. I am saying when a speaker is amplified, you can play it louder and still be clear, well when you do that you are going to need to turn up the rears to get the same fill sound effect(not the same volume) thus turning up the volume on the HU putting more distortion to your rears. Ask any real car audio competitor, you want CLEAN power. As I said before a HU only puts out 10 to 15 watts of clean power. Even if it says 50 watts, that is not clean. Basically because your fronts can go louder you need to turn up your rears to get the same effect you had when they were all playing off the HU.I personally like to have some sound in the rears but that is because I play a lot of movies in my car and I like surround sound.

Of course amplifiers can blow speakers, but they blow speakers by puting too much power towards them rather than too much distortion. I also prefer to teach the user rather than prevent but it is very tough considering we cant go to the persons car and every ear is different. I am just going by experience.
 
autosoundnut said:
Ask any real car audio competitor, you want CLEAN power. QUOTE]

okay

"hey sndsgood"

" yes"

" u want clean power right?"

"yes"

"do u want rear speakers"

"no, i took my rear speakers out in 98 and stopped running them"

"but why sndsgood allot of people like souround sound and they like to have an accurate rear fill"

"well my find feathered friend let me explain a few things

lets look at a few diffrent issued concerning this discussion and i'll try to answer them as best as i can

first the rear fill debate. hey i'm all for an accurate rear fill. if there was a processor out there to simumate accurate rear fill i'd run it, but heres the problem. rear fill is basically the sounds that emulate from the stage bouncing off the rear walls. in allot of instances these are reflections that are traveling 20-40 or more feet away. now the reflections that u hear from behind sound in no way the same as the original image, bouncing around and reflecting off of any surface will change the sound. so to get this sound in the car it in no way can be accurate with rear speakers. for one if your not using time delay, the sound will be pretty much the same as the sound coming from the front, it will come at the same time nearly the same level and with allot less reflections. therefore it is in no way accurate. the best you could do and what a few guys have done is set up the rearp speakers independantly, and aim them towards the back glass to try and get some more reflections out of them and adding in time delay to try and aheive a bigger soundstage. in my opinion even this method has less then accurate results.


surround sound.

i always kind of find this one funny because generally when i ask them what surround sound processors they are using, they generally say they are not. so i ask them how can it be surround sound like the movies if the rear speakers are playing the exact same image as the front, a cd only has two channels basically. a left and a right, it doesnt have a rear right and a rear left and front left and front right. unless your using a specific surround processor, and dvd's specifically made to play in that format. so unless that is happening it won't be accurate.


volume

now your are right in that the head unit will send out distorted power, but what your forgetting is that so will a amplifier, when you set your gains you set them up for the weakest speakers first, finding out at what volume the rears can play their maximum undistorted volume. then you move on to the next part wich is generally the amp. now if u know your rear speakers begin distortion on say 20 of your headunit, then you set your amps gain so it reaches maximum power at 20 on your headunit, and do the same thing for your sub, this is level matching and when done you will never distort a single speaker in your car. this may be why in over 15 years in this hobby, i have never blown a speaker (well except for this one infinity 12 but that was on porpouse for the fun of it)


speakers

for the most part more speakers are blown from a clipped signal then anything else. over powering a speaker is hardly the reason. a clipped signal at 50 watts can destroy a speaker capable of 500 watts. and ive seen amps rated at 500 watts take over 700+ or more watts cleanly and not even sweat."


imaging

now as far as imaging is concerned, i'd rather have all my speakers up front, all my power up front, and if i ever get the car close enough to how i like it i'll problaby even put a 10" sub up front in the dash. this is to create an accurate soundstage such that u are sitting in the audience at a live concert. rear speakers amplified to loudly can pull the soundstage back, and now you turning the gain down and using maybe 15% of amplifier power just for a bit of unrealistic unnatural rear fill. i'd rather take that amplifier and push a few extra watts to the speakers up front. when i took my rear speakers out and pushed more power to the fronts. people didnt beleive me when i told them i no longer had rear speakers, it got to the point where i mounted my fuse blocks in the rear speakers holes and make the grills quick disconnect so i could prove that i had no speakers back there. would i run rear speakers? yes if i had a vehicle of large size like an suv or something similar, and even then my rear speakers would be off of headunit power (if i had any< i generally buy head units with no built in power) or off of a very small amp. and those speakers would be stricly for rear seat enjoyment. nothing more.


teaching


i say teach people the proper way of doing things even if it is tougher so more people can become educated. i see so many kids coming on forums and tellig how they blew their sub so they think, either their sub is junk or their amp is junk. and they go out spend more money, and do it all over again."



sorry for my spelling, and this post wasn't meant to offend anyones beliefs, they are just things ive picked up in my years in the hobby...
 
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autosoundnut said:
1sty, putting a fuse on the speaker will do absolutely nothing unless you are going to put voltage through it.(which you obviously would never do.) If you want to somewhat protect a speaker you need to put on a cap or some people call them a bass blocker.
Yes I've heard the difference many times, I was an installer for several years don't forget :D

You might want to tell alpine that putting fuses in their crossovers are useless then. They have been for a few years now.

A clipped signal becomes a DC signal so a small DC fuse will pop under a clipped AC signal (audio) and, in my experience, even a powerfull enough clean signal aswell. Ofcoarse you can always just measure the AC signal with a DMM and use a properly sized AC fuse.

Capacitors do not protect tweeters from distortion except in that they suck up some of the power themselves. They just provide 6 db of high pass attinuation.


In my conversations with various compeditors I have heard of 3 main reasons they use rear speakers.
1. They have to per the rules (yes they are usualy amped if there)
2. To create an ambiance or consuming effect even if only very slightyl.
3. to widen the front stage behond the cars side windows.
 
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Nicely said sndsgood, despite the spelling ;)
As a bit of a home theatre nut, I feel I know more about this area than car audio. And I can tell you that even a poorly set up DTS or DD 5.1/6.1/7.1 system sounds poor, and thats with processor and encoding of dedicated "fill" audio to send to the rear/side speakers. You still have to set it up right and adjust speakers finely.

Car audio has many problems in that there are more restrictions on the practical location of speakers and the audience (if only I could drive with my head on the gear stick...).

With just these problems alone, getting good front stage imaging is hard enough. Adding in rear speakers that are essentially completely hidden from your ears (i.e. no direct path with seats/headrests in the way, speakers essentially facing each other instead of aimed at your head, etc) makes the challenge of setting up high fidelity car audio systems particularly difficult.

With this in mind, it could quite strongly be argued (which is essentially what snsdgood is doing) that any rear speakers could actually be considered detrimental to the sound instead of adding value.

Subjectively speaking, I like a bit of "rear fill" in that it simply "sounds better" to have a slight signal sent to the rear speakers. Would I amp it? No way. Do I thus feel it is justified to state that this is a waste of money, yes I do.

And this argument has nothing to do with whether or not you are causing damage to your equipment with "clean" power, clipping, or anything, its simply unnecessary.

On top of this, I don't buy the "clean" power argument either as I still assert that setting up your equipment properly negates this concern.
 
I wouldn't go that far. It all depends on the listener. Some people really like rear sound or a consuming sound. For these people rear speakers are certainly not worthless.
Also in the relom of copetition and even average audio lover, amping aftermarket rear speakers can add alot of flexibility to a system. Its one of those things thats always good to have and you really need to try it in a car before knowing it will be useless. In some cars it can be very useful.

I am going to be using some JL audio XR525CW mids only in my rear doors. My JL audio 300/4 will be providing the power and some of the crossover. Although I am only using them becuase I got them cheap. :D
 
All I am trying to say is that the difference is a scientific argument vs. a personal opinion.

We used to get into this on the Home Theatre board I was a member of.

If you buy a HT subwoofer, it generally has an artifical boost in the 35 Hz - 45Hz range. They also tend to perform poorly below 30Hz. This gives you that punch in the gut bass that I must confess as a hip hop fan does feel/sound pretty awesome.

However, the anal argument always went along the lines of two camps:
"accurate reproduction of sound as the director intended" vs. "impressive punch in the gut sound (inherent in this argument is that it is not accurate but feels good)"

So, I built a monster HT subwoofer - see pics here:
http://www3.sympatico.ca/robin.smith1/Sonosub/

I disabled the artifical bass boost in the plate amp I bought, and even invested in a parametric equalizer which I then used to tune the flatest bass response I could (my sub goes down to 18Hz). (See attachment if you are interested in the plot, blue is beofre tuning, pink is after).

Obvioulsy I bought into the "accurate reproduction of sound" camp, although I try not to be too opinionated with my feelings.

Anyway, sndsgood's argument reminded me of these HT discussions, and I think he makes many valid points.

While the car audio competition industry may focus on things like SPL, I prefer sound quality, of which, I believe, you have been a vocal proponent 1sty. Part of SQ I think involves accurate reproduction of sound. As has been said many a time before, music usually comes from in front of you, and thus focusing on the front soundstage, perhaps even ignoring rears altogether may indeed result in the best reproduction of sound. This doesn't mean you will like it the best, just that it is possibly more accurate.

I know that in my car system (which is really not that good, so take some of what I am saying with a pinch of salt) I probably have the bass boosted higher than the "accurate reproduction of sound" model would dictate. But I like it. So I did it.

Am I rambling? Anyway, I hope I made sense...
 

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in dealing with competition you have two competitons, one geared strictly for spl and another geared strictly for sound quality.

and from competing and judging one of the most widely use sentances from a judge during sq testing is " your bass it to loud"

the second used sentance is "not enough midbass"
 
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