Anyone know if the speakers behind the headrests in the back seat are actually speakers or subs?

I dunno yet... I haven't looked but I assume they are the subs... I find that mine bottom out WAY to easy! I like NIN and alot of heavier rock/industrial stuff that loaded with BASS and I can't turn it up for risk of the things destroying themselves...

Anyone got some tips on these and how to smooth that out? or do I have a blown speaker...

Sorry for the thread H/J

I dunno yet... I haven't looked but I assume they are the subs... I find that mine bottom out WAY to easy! I like NIN and alot of heavier rock/industrial stuff that loaded with BASS and I can't turn it up for risk of the things destroying themselves...

Anyone got some tips on these and how to smooth that out? or do I have a blown speaker...

Sorry for the thread H/J

IMO, just leave the stock stuff in if that's the music you listen to. Nothing will destroy a speaker quicker than distortion. And NIN is almost all distortion. LOL

Total myth. The ONLY thing that destroys speakers is too much power. You can exceed the power limits thermally (over time) or mechanically (instantaneously). In the case of ADV1 it is unknown if you are exceeding the limits of the amplifier and clipping the signal to the woofer or actually exceeding the woofer's mechanical limits. Likely it is the former as no engineer worth anything would design a system for potential failure. Sending a clipped signal into the driver, as long as the driver(s) can manage the thermal and mechanical load, does nothing more than heat up the amplifier and make it sound like a$$.
Sounds like it is time for an upgrade in the subwoofer department. I'm not familiar with the G8 specifically, but presume it is using something along the lines of 6"-8" woofers in the rear deck. Quite a few manufacturers make subwoofer drivers in this size suitable for free-air application. You will also need something a bit more robust to power the new drivers as well.

Would this be good replacement woofers? The sub's in the G8 are 8" right? These are also 8". Would you be able to just swap out woofers without changing the amp? These look like they should work. Is the G8's amp stable down to 4 ohms and if it is, how much power does it give under a 4 ohm load?

http://www.onlinecarstereo.com/CarAudio/ProductDetail.aspx?ProductID=13307

Anyone got some tips on these and how to smooth that out? or do I have a blown speaker...

You can turn down the amp in the trunk, just like you can turn it up! try adjusting this. it's located at the bottom of the amp, there are pictures over at http://www.g8board.com/forums/showthread.php?t=1617

Would this be good replacement woofers? The sub's in the G8 are 8" right? These are also 8". Would you be able to just swap out woofers without changing the amp? These look like they should work. Is the G8's amp stable down to 4 ohms and if it is, how much power does it give under a 4 ohm load?

http://www.onlinecarstereo.com/CarAudio/ProductDetail.aspx?ProductID=13307

MTX isn't bad but the stock amp is not very powerful so you should look for a sub with a higher sensitivity. Of course I would recommend Infinity, since their 8" is around $10 more than the MTX on that same site but has a much higher sensitivity (will play louder with the same wattage)

Total myth. The ONLY thing that destroys speakers is too much power. You can exceed the power limits thermally (over time) or mechanically (instantaneously). In the case of ADV1 it is unknown if you are exceeding the limits of the amplifier and clipping the signal to the woofer or actually exceeding the woofer's mechanical limits. Likely it is the former as no engineer worth anything would design a system for potential failure. Sending a clipped signal into the driver, as long as the driver(s) can manage the thermal and mechanical load, does nothing more than heat up the amplifier and make it sound like a$$.
Sounds like it is time for an upgrade in the subwoofer department. I'm not familiar with the G8 specifically, but presume it is using something along the lines of 6"-8" woofers in the rear deck. Quite a few manufacturers make subwoofer drivers in this size suitable for free-air application. You will also need something a bit more robust to power the new drivers as well.

so then what if your amp has too little power and you crank the gain up and the amp starts clipping? Now you can destroy your speaker with "too little power" i.e voice coil is overheated...

What do you guys think of two 8" w7 from JL AUDIO?

You're talking about these Infinity's correct?

http://www.onlinecarstereo.com/CarAudio/ProductDetail.aspx?ProductID=18598

I dunno yet... I haven't looked but I assume they are the subs... I find that mine bottom out WAY to easy! I like NIN and alot of heavier rock/industrial stuff that loaded with BASS and I can't turn it up for risk of the things destroying themselves...

Anyone got some tips on these and how to smooth that out? or do I have a blown speaker...

Sorry for the thread H/J

A quick fix is to set the Dynamic Distortion Limiter.

If you go into the audio setup menu you should find a DDL setting. Make sure this isn't set to 0. The higher you set it the cleaner the sound will be from the audio system. The tradeoff is that the higher you set it, the more it will limit your maximum volume.

I would suggest 1 or 2, I personally go with 1 because you get the most volume with just an acceptable (depending on the listener, and music) small amount of distortion. Any higher and I cant make the music loud enough for me.

And yes the speakers in the package shelf behind the rear seat are 8" woofers.

COOL! I'll give that a shot!

OK, that didn't work... Come to find out it was already set to 2. I tried it at all the levels on one of the songs that gives me the worse sound and no change.

You can hear it bottoming out and I just get a real bad Rattle comming from the back... Not a good sound at all. Maybe I should be looking at some better subs :(

Total myth. The ONLY thing that destroys speakers is too much power. You can exceed the power limits thermally (over time) or mechanically (instantaneously). In the case of ADV1 it is unknown if you are exceeding the limits of the amplifier and clipping the signal to the woofer or actually exceeding the woofer's mechanical limits. Likely it is the former as no engineer worth anything would design a system for potential failure. Sending a clipped signal into the driver, as long as the driver(s) can manage the thermal and mechanical load, does nothing more than heat up the amplifier and make it sound like a$$.
Sounds like it is time for an upgrade in the subwoofer department. I'm not familiar with the G8 specifically, but presume it is using something along the lines of 6"-8" woofers in the rear deck. Quite a few manufacturers make subwoofer drivers in this size suitable for free-air application. You will also need something a bit more robust to power the new drivers as well.


Anyone that has been in the car audio industry for over 10 minutes has seen the effects of distortion on speakers. Power is not the enemy if the system is tuned correctly. If you are thermally breaking down a speaker its due to gains being set incorrectly which creates distortion.

I vouch for Dodson!

And... keep them ear plugs handy...


RRM

Anyone that has been in the car audio industry for over 10 minutes has seen the effects of distortion on speakers. Power is not the enemy if the system is tuned correctly. If you are thermally breaking down a speaker its due to gains being set incorrectly which creates distortion.

I was about to say the same. Distortion is the enemy.

Yes I agree. More powerful amps have a less likely chance of blowing drivers than weaker amps. When an amp runs out of clean power it starts to produce distorted power up to seven times that of it's rated output power causing damage to speaker drivers. More clean power is the way to go but still be careful because there is a limit. Being a DJ I have to know these things.

Would any 8 inch woofer fit in the current woofers place or would you need a bracket of some sort?

So, could the Amp be the cause of this Sub distortion/bottoming out issue I'm having? Perhaps there isn't enough power?

Sorry, I'm a newb when it comes to car audio...

Two things;

First, are you sure your noise ISN"T a rattle? I'm willing to bet there is something loose near the speakers that you are hearing.

Second, for some reason most people don't realize that distortion will blow speakers because it IS an increase in power.

Clipping (distortion) is when the rising AC signal can no longer increase, thus just holds steady - clipping the tops of the waves and making them flat. These flat areas in the signal are now DC rather than AC. DC at any voltage level is much higher in real power (heat)than an AC signal of the same level would be.

Yes...the rear deck speakers are 8" subs.

I dunno about the amp, but I just replaced the 30W 2Ohm stock speakers with 75W RMS 2Ohm Infinity speakers, and I start to get distorted at around 25. Most certainly the lack of power from the head unit causing the distortion, not the speakers.

The amp does a pretty good job with the subs...good enough for me at least. It won't shake your pancreas loose, but it fills the car (and rattles my license plate a little).

Chances are for you ADV1, it's the fact that you have 8" subs and not 10" or 12" subs. Some of the bass from NIN is deeeeeeeeppppp, very low freq. I had a 12" CVs back when I was in college (10 yrs ago) and NIN would pound with it. Typically, I don't think the 8" subs can reproduce the bass as well as the 10" or 12" subs.

Anyone else have thoughts?

Anyone that has been in the car audio industry for over 10 minutes has seen the effects of distortion on speakers. Power is not the enemy if the system is tuned correctly. If you are thermally breaking down a speaker its due to gains being set incorrectly which creates distortion.

+2! over 10 years in the audio/video bizz distortion kills:slap:!

I clipped the deck speaker wires and added a couple of tens in boxes. Granted it doesn't bust a nut running off the stock amp, but, you don't hear the back tray rattling where the stock subs are mounted and the bass is clean. Once I get my amp in I'll replace the rear deck speakers with another 8" memphis speakers, but, not subs. I'll probably replace the door speakers with Memphis also. My truck is killer with all memphis speakers and 1000 watts of power and one 8" sub that did 130 dbs at a sound competition last year and didn't even win. This car will never be even close to my truck, but, I'm not trying to get there either. Just clean it all up and you'll enjoy the ride a lot more.

Wattta you say??? I kant hear you.... THink it's my sub-wooffers on the side of my head.
(or the tweeters in my brain).....

Think smart... Save your ears...

RRM

First off a speaker has no way to decipher the type of signal incoming (distorted, clipped, clean) nor does it care. It only responds to the signal it is fed and if it operates within its thermal and mechanical limitations it survives. Again, you can only kill a speaker by exceeding thermal capabilities or mechanical capabilities. You can't kill a speaker any other way.

Saying distortion kills speakers is just foolish. If distortion killed speakers would you see Marshall cabinets stacked to the ceiling with all sorts of devices between guitar and speaker to ADD distortion?

Let's get to the root of your ignorance here.

Music has a crest factor (difference between average and peak level). In modern popular music the crest factor is typically 10-15db. A pure sine wave has a crest factor of 3db. A square wave (clipped signal) has a crest factor of 0db.

When we rate amplifiers we base it on the average amount of power produced while reproducing a sine-wave into a given load. This is the amplifiers RMS power. If you are familiar with audio you already know that to increase your level 3db, you must double the power. Based on this information you should be able to see that when you clip an amplifier the speaker connected to it actually sees double the power it is rated for (3db additional output to produce the square wave over the sine wave that the amp was rated at.)

So let's assume a hypothetical amplifier:

100 watts RMS power:
Average power output when producing music with 10 db crest factor: ~ 12.5 watts
Average power output when producing a sine-wave: 100 watts
Average power output when producing a square-wave: 200 watts <- this is a clipped signal to the speaker.

So how can we kill a speaker by "underpowering it"? Well, we can't but read-on to see where the confusion comes from.

We have our hypothetical 100 watt amplifier, so let's add in a hypothetical speaker that is rated for 150 watts RMS. A seemingly good match as it should take whatever the amplifier can throw at it since the power rating is 1.5 times the output rating of the amplifier. But wait, remember what happens when we clip that amplifier? It acts like a 200 watt amplifier instead of the 100 watts it is rated for, exceeding the thermal capabilities of the speaker by 50 watts resulting in OVER POWERING not under powering it. Keep at it long enough and the speaker succumbs to failure from too much average power (heat.)

You will never kill a speaker from underpowering period. End of story!

Saying distortion kills speakers is just foolish. If distortion killed speakers would you see Marshall cabinets stacked to the ceiling with all sorts of devices between guitar and speaker to ADD distortion?

rsvchad, I call :bs:

Distortion kills speakers.

BTW, my amps are all rated higher than my speakers, which allows me to keep my gains low, my ohms high, and my signal very clean. having a underrated amp will also kill speakers due to trying to exceed it's limits. Distortion comes from the signal source, not added muscial devices made to "add distortion" to a song.

I've been in the Car Audio, Home Audio, and Recording Studio Audio for about 20 years. Distortion kills speakers.

First off a speaker has no way to decipher the type of signal incoming (distorted, clipped, clean) nor does it care. It only responds to the signal it is fed and if it operates within its thermal and mechanical limitations it survives. Again, you can only kill a speaker by exceeding thermal capabilities or mechanical capabilities. You can't kill a speaker any other way.

Saying distortion kills speakers is just foolish. If distortion killed speakers would you see Marshall cabinets stacked to the ceiling with all sorts of devices between guitar and speaker to ADD distortion?

Let's get to the root of your ignorance here.

Music has a crest factor (difference between average and peak level). In modern popular music the crest factor is typically 10-15db. A pure sine wave has a crest factor of 3db. A square wave (clipped signal) has a crest factor of 0db.

When we rate amplifiers we base it on the average amount of power produced while reproducing a sine-wave into a given load. This is the amplifiers RMS power. If you are familiar with audio you already know that to increase your level 3db, you must double the power. Based on this information you should be able to see that when you clip an amplifier the speaker connected to it actually sees double the power it is rated for (3db additional output to produce the square wave over the sine wave that the amp was rated at.)

So let's assume a hypothetical amplifier:

100 watts RMS power:
Average power output when producing music with 10 db crest factor: ~ 12.5 watts
Average power output when producing a sine-wave: 100 watts
Average power output when producing a square-wave: 200 watts <- this is a clipped signal to the speaker.

So how can we kill a speaker by "underpowering it"? Well, we can't but read-on to see where the confusion comes from.

We have our hypothetical 100 watt amplifier, so let's add in a hypothetical speaker that is rated for 150 watts RMS. A seemingly good match as it should take whatever the amplifier can throw at it since the power rating is 1.5 times the output rating of the amplifier. But wait, remember what happens when we clip that amplifier? It acts like a 200 watt amplifier instead of the 100 watts it is rated for, exceeding the thermal capabilities of the speaker by 50 watts resulting in OVER POWERING not under powering it. Keep at it long enough and the speaker succumbs to failure from too much average power (heat.)

You will never kill a speaker from underpowering period. End of story!

Spoken like an engineer that actually knows what he's talking about... Good Job! :hail:

Spoken like an engineer that actually knows what he's talking about... Good Job! :hail:

Now spoken like some one that had delt with the real world wokings of distortion caused by under powering speakers for 10+ years... if you take the numper of blown speakers (or subs) that i have changed out that were blown from distortion (to little power/improper tunninning) versus too much power is like 75 to 1! a factory radio will blow speakers all day long bc people crank up the bass till it distorts and we ALL know that the factory system doesnt have too much power.


P.S. RVS stated that "you can only kill a speaker by exceeding thermal capabilities or mechanical capabilities" wouldnt distortion be exceding the mechanical capabilites? :confused::confused:

You're talking about these Infinity's correct?

http://www.onlinecarstereo.com/CarAudio/ProductDetail.aspx?ProductID=18598


yep :)

IMO, do not use any form of subwoofer in the rear deck of any car if you care about sound quality. By putting subwoofers in the rear deck, the higher natural frequencies the cone makes will bounce off the rear windsheild and shoot to the front listeners, therefore creating the image of bass coming from behind you, instead of in front of you. Also, the first thing I would put in the sound system is the JL Audio Clean Sweep, it flattens out the sh*%%y signal that the factory head unit produces, and gives you much better sound quality, meaning less distortion as well, you can find these here:

http://mobile.jlaudio.com/products_cleansweep_pages.php?page_id=94

Wow! Geat to see all this discussion an amps and distortion. Love that people are trying to better their understanding. Let's just make sure everyone has the right attitude. Calling someone "ignorant" may not be the right attitude to have.

rsvchad makes some good points, and it does need to be said that there are many different types of distortion. Yes the "distortion" recorded into a song ,ay sound nasty, but the signal going to the speaker is clean, so I agree that the speaker doesn't know or care. The distortion that is bad is when an underpowered amp goes into clipping due to typically users wanting more power than it is capable of producing cleanly and the resulting high powered square wave causes too much heat on the voice coil, (if anyone wants more detail on this, just ask) therefore "killing" the speaker. So I guess technically, we are both right. Distortion is a bit of an all-inclusive term to most people.

And I appreciate the opinions of those in the industry. Though I am certainly not an engineer, I have been "in the industry" since 1989 and have a decent understanding of things.

IMO, do not use any form of subwoofer in the rear deck of any car if you care about sound quality. By putting subwoofers in the rear deck, the higher natural frequencies the cone makes will bounce off the rear windsheild and shoot to the front listeners, therefore creating the image of bass coming from behind you, instead of in front of you. Also, the first thing I would put in the sound system is the JL Audio Clean Sweep, it flattens out the sh*%%y signal that the factory head unit produces, and gives you much better sound quality, meaning less distortion as well, you can find these here:

http://mobile.jlaudio.com/products_cleansweep_pages.php?page_id=94

You make a good point regarding rear decks but two point sshould be made. 1. The lower frequencies produced by an 8" woofer are not nearly as directional, and therefore affected, by the glass reflection issue. 2. the 6" woofers in the doors will produce decent bass up front, and the fact remains that there is nowhere up front to put a 8" or larger subwoofer. In theory, a clean subwoofer will not be localized but in reality, in a car, you will likely be able to tell it is behind you.

That said, with proper soundstage and "tweaking", so can eliminate a lot of that when using good equipment and a good install. In my regular cab truck I have a rear-firing (out of necessity)10" JBL sub in a center console and with most music, the bass seems to be coming from my door speakers. Never underestimate the power of a good calibration! :)

Very True ^. If you have a good subwoofer in your trunk firing towards the rear of the car, you cant tell where it is coming from, I have a JL audio 12w6v2 and I cant tell its coming from the rear, before that sub, I had a kicker in the same setup and could easily tell it was coming from behind me.

Two things;

First, are you sure your noise ISN"T a rattle? I'm willing to bet there is something loose near the speakers that you are hearing.

Second, for some reason most people don't realize that distortion will blow speakers because it IS an increase in power.

Clipping (distortion) is when the rising AC signal can no longer increase, thus just holds steady - clipping the tops of the waves and making them flat. These flat areas in the signal are now DC rather than AC. DC at any voltage level is much higher in real power (heat)than an AC signal of the same level would be.


Absolutely right! Also, about the possibility of it being panel flex or rattle creating the noise your hearing, this is very likely. I've seen many customers come in thinking they had blown speakers, only to find that they had sunglasses in the console(with JL stealthbox) and they were vibrating making the noise. With subwoofers mounted on a rear parcel shelf that is likely not the most reinforced item on a car I could see it causing the annoying noise. I can't wait to get my car in so I can rip it apart and put all new gear in it. This radio issue is giving me problems though, I'm not sure how I'm going to process it yet...if the A/V input in the G8 radio exists I may build a small car PC for the back, and output that through a PXA-h701 processor to feed the 3 amps I'm planning on using. I think that may be the best bet. I've already found a rotary knob that serves as a mouse similar to the I-drive in BMW's that I can interface to a PC....

Two things;

First, are you sure your noise ISN"T a rattle? I'm willing to bet there is something loose near the speakers that you are hearing.



What I have is this... Speaker bottoming out, bad distortion followed by the package tray rattling... I have looked it all over and everything appears to be tight.

Do you think a sound deading material that I can put on the bottom of the tray to help get rid of the rattle? followed by a nice pair of Infinity Subs to clear up the sound?

What I have is this... Speaker bottoming out, bad distortion followed by the package tray rattling... I have looked it all over and everything appears to be tight.

Do you think a sound deading material that I can put on the bottom of the tray to help get rid of the rattle? followed by a nice pair of Infinity Subs to clear up the sound?


If the metal or plastic pieces themselves are rattling, then yes. If it is two pieces rattling at their joint, you may need a stronger fastener, or whatever.

Regarding replacement subs, Infinity is great stuff. Just remember that a speaker can AT BEST only output what it is fed. If the signal is crap or the amp is not strong enough, you may have issues. Though I belive your problem is not enough bass, so you turn it up and the subs "bottom out". The Infinity is a good replacement then because it is very efficient and will get loud with that obviously small factory amp. Just be sure to separate the airspace between front to back, if you are not going to enclose the rear of the woofers, i.e. a sub box. I am anxious to hear your results, especially if you dont use an enclosure since these are not technically "free-air" subs.

All i would like to know is if i can take out the stock subs and put in stock 8w7 from JL audio. The real question here is... Will it work with free air? or do i definately need a box because if i use free air it will save space...

All i would like to know is if i can take out the stock subs and put in stock 8w7 from JL audio. The real question here is... Will it work with free air? or do i definately need a box because if i use free air it will save space...


You need to check the specs on the JL subs you are talking about. They should give you a layout for cubic feet of air space for the speakers.



Side note: I did not know that you could adjust the amp in the trunk. Can you tell me where it is located? I'm having the same issue with the subs as you guys...Not enough balls. Of course, they are 8's so they can't reproduce the lower frequencies as well as 10's or 12's; but I don't want to install more stuff if I don't have to.

I appologize if I offended anyone with the use of the word ignorant. It was meant as a general lack of understanding on the subject, which is exactly what I see. It's okay to be ignorant on subject matter, but foolish to argue against proven science. I'm here because I'm totally ignorant on the G8 and want to learn more about the car. If I knew everything about it and how to make it better then I would have no reason to be here.

I feel like I've already derailed the thread from the intent of the original poster, but to touch on a couple of items:


rsvchad, I call :bs:

Distortion kills speakers.

BTW, my amps are all rated higher than my speakers, which allows me to keep my gains low, my ohms high, and my signal very clean. having a underrated amp will also kill speakers due to trying to exceed it's limits. Distortion comes from the signal source, not added muscial devices made to "add distortion" to a song.

I've been in the Car Audio, Home Audio, and Recording Studio Audio for about 20 years. Distortion kills speakers.

I digress my friend. You know what they say: You can lead a horse to water...

Perhaps after another 20 years "in the industry" you will have the basics down.


Now spoken like some one that had delt with the real world wokings of distortion caused by under powering speakers for 10+ years... if you take the numper of blown speakers (or subs) that i have changed out that were blown from distortion (to little power/improper tunninning) versus too much power is like 75 to 1! a factory radio will blow speakers all day long bc people crank up the bass till it distorts and we ALL know that the factory system doesnt have too much power.


P.S. RVS stated that "you can only kill a speaker by exceeding thermal capabilities or mechanical capabilities" wouldnt distortion be exceding the mechanical capabilites? :confused::confused:

Again speakers can be damaged two ways. Distortion and clipping are not the two ways. Mechanical failure is when a driver experiences instantaneous failure such as the voice coil jumping out of the gap or deforming against the back plate, the spider seperating/tearing, the surround seperating/tearing or the cone deforming/tearing. Mechanical failure is typically very obvious upon basic visual inspection. Mechanical failure is a symptyom of grossly overpowering a driver.

If you are interested in further reading on the subject matter: http://www.audiogroupforum.com/csforum/showthread.php?t=4332&highlight=clipping+blown

This thread is a wonderful discussion that dives deeper into the matter of clipping, distrtion and killing speakers than I've touched on here. There are many industry insiders (principal level and engineers) from JBL/Harman group, JL Audio along with one of the most prevalent faces in IASCA (International Auto Sound Challenge Association). They all state the EXACT things I have stated here, although much of it is more in depth. Within the discussion you will likely find links to Pro sound sites, such as Rane, reiterating the same information yet again. Perhaps all these guys that do this for a living (including me) are wrong and have been mislead, but I'm pretty sure that is NOT the case.

All i would like to know is if i can take out the stock subs and put in stock 8w7 from JL audio. The real question here is... Will it work with free air? or do i definately need a box because if i use free air it will save space...

A sub in the prober box will sound better than a free air sub. your main proubem is going to be power. the rear speakers (from what i have seen so far) are just single cone speakers with low range sent to them. the factory amp doesnt really have enough power to push aftermarked subs well. if you want to power some real subs just get a sub amp and the porper converers to run it off of the factory system and be done with it.

rsvchad
"Perhaps all these guys that do this for a living (including me) are wrong and have been mislead, but I'm pretty sure that is NOT the case. " so some how what i have been taught over the past 10 years (along with alot of the other members on here) from the same places that you quote you got your info from are wrong but you are right? I just have a hard time beleiving that i made it 10+ years in my job doing every thing wrong. But to each his or her own.

not being an engineer or anything, i do have experience with blowing up speakers. did you have the bass on the head unit cut up? if so this will be a major problem at high volume levels, if you want more bass, get some subs and an amp. you can't overcompensate a weak sound system by adjusting the audio settings in the headunit. and speaking of headunits, i was always told by my installer friends that the main enemy of speakers is the volume knob on the radio. the higher it gets, the more distortion sent to the speaker. putting an amp on the same speakers to give them more juice will get you louder db without having to crank the volume knob to capacity. think of a man running, when the runner is weaker he has to try harder to reach a certain speed, but when he is stronger he can achieve the same results with less effort and therefore doesn't burn out as quickly. at least this is what i have always been told. but that is just a common sense approach, sometimes engineers forget about thinking with their heads and not with their calculators..

no offense to engineers, i am an engineering clerk after all. :)

First off a speaker has no way to decipher the type of signal incoming (distorted, clipped, clean) nor does it care. It only responds to the signal it is fed and if it operates within its thermal and mechanical limitations it survives. Again, you can only kill a speaker by exceeding thermal capabilities or mechanical capabilities. You can't kill a speaker any other way.

Saying distortion kills speakers is just foolish. If distortion killed speakers would you see Marshall cabinets stacked to the ceiling with all sorts of devices between guitar and speaker to ADD distortion?

Let's get to the root of your ignorance here.

Music has a crest factor (difference between average and peak level). In modern popular music the crest factor is typically 10-15db. A pure sine wave has a crest factor of 3db. A square wave (clipped signal) has a crest factor of 0db.

When we rate amplifiers we base it on the average amount of power produced while reproducing a sine-wave into a given load. This is the amplifiers RMS power. If you are familiar with audio you already know that to increase your level 3db, you must double the power. Based on this information you should be able to see that when you clip an amplifier the speaker connected to it actually sees double the power it is rated for (3db additional output to produce the square wave over the sine wave that the amp was rated at.)

So let's assume a hypothetical amplifier:

100 watts RMS power:
Average power output when producing music with 10 db crest factor: ~ 12.5 watts
Average power output when producing a sine-wave: 100 watts
Average power output when producing a square-wave: 200 watts <- this is a clipped signal to the speaker.

So how can we kill a speaker by "underpowering it"? Well, we can't but read-on to see where the confusion comes from.

We have our hypothetical 100 watt amplifier, so let's add in a hypothetical speaker that is rated for 150 watts RMS. A seemingly good match as it should take whatever the amplifier can throw at it since the power rating is 1.5 times the output rating of the amplifier. But wait, remember what happens when we clip that amplifier? It acts like a 200 watt amplifier instead of the 100 watts it is rated for, exceeding the thermal capabilities of the speaker by 50 watts resulting in OVER POWERING not under powering it. Keep at it long enough and the speaker succumbs to failure from too much average power (heat.)

You will never kill a speaker from underpowering period. End of story!

You are correct, I apologize and before I post the rest of this let me say your posts come off EXTREMELY arrogant. If my any of posts came off the same way I apologize. That's not what I intended. I have no problem having a discussion about this and learning something new. But, when you say "let's get to the root of your ignorance" and call me "foolish", there is absolutely NO need for that at all.

The stuff below this is not from me. It's from the owner of a VERY good amp company that he actually built from the ground up.

"He is actually correct - When people refer to under-powering a speaker
to death they mean using an amp that is too small that ends up clipping
the speaker to death.

For instance...

100 watt speaker w/ 75 watt amplifier
* Clipped to 150 watts, kills speaker (high level of distortion will be
present)

100 watt speaker w/ 100 watt amplifier
* Able to power speaker adequately without clipping and speaker is fine

The problem is people with small amps cranking them up like crazy trying
to get the output of a larger amp, thus clipping the output (more
power), and killing the driver. In essence distortion *kind of* does
kill the speaker as a square wave is distorted but also does contain
more power, so more power is still the root cause but the distortion is
a symptom of more power from the square wave. The distortion itself
isn't the issue, it is the added power due to the distortion.

This is why a guitar cabinet distorted all to hell doesn't blow... say
they use a 50-watt head amp but the driver can handle 250-watts. No
matter how bad you clip that 50-watt amp the driver won't blow as the
50-watt amp can only be clipped into around 100 watts of output. Say
they used a 150 watt amp... thats another story, it could be clipped to
~300 watts and kill the driver."

A sub in the prober box will sound better than a free air sub. your main proubem is going to be power. the rear speakers (from what i have seen so far) are just single cone speakers with low range sent to them. the factory amp doesnt really have enough power to push aftermarked subs well. if you want to power some real subs just get a sub amp and the porper converers to run it off of the factory system and be done with it.

rsvchad
"Perhaps all these guys that do this for a living (including me) are wrong and have been mislead, but I'm pretty sure that is NOT the case. " so some how what i have been taught over the past 10 years (along with alot of the other members on here) from the same places that you quote you got your info from are wrong but you are right? I just have a hard time beleiving that i made it 10+ years in my job doing every thing wrong. But to each his or her own.

I'm having a hard time following what you are saying here. Nonetheless my information comes from text books, classes and real world experience. Did you read the thread I linked? While there a few on there that are "lost," all of the industry guys and most of the hobbyist understand the concepts. I don't understand your comment about they are wrong, but I'm correct.

I can believe you've survived for 10 years in the industry working on the retail sales floor. I've heard things on sales floors that almost made me burst out in hysteria. A good sales person can blow smoke all day long and make sales, if they are convincing enough. Rarely will you run up against someone that has superior general knowledge on the subject. If that weren't the case we wouldn't have companies selling wire and other snake oil that costs astronomical amounts of money witout any legitimate proof of performance.

Dodson,

I appologize. Again I was not trying to point fingers at any one individual. I was trying to address the whole.

I dont sell the stuff, i install the stuff. the only smoke i see is from the blown speakers. HAHA j/k.
No i have not had a chance to read the link you posted but i will be sure to. What i was trying to say (through all the confusion in my last post) is that you tell us what you know and state that you have gone throgh all this training and there for you must be right. yet i have also gone through years of training and i feel that i am right (the reason we butt heads here). I know that i dont know everything but i do have a very hard time beleaving that all the years of training i have gone trough and after all the certifications i have recived that everyone of the venders have taught me the same thing and (and yet) that everyone of then have taught me the wrong thing.