On Saturday my front component tweeters blew and my rear tweets to. So today from my drive from work to home ( about 20 mins) my 550x got really hot I couldnt bare to keep my hand on there for more than 6-8seconds. I touched my 550s and its fine it was just warm like always. My current temporary CD player has 2 preouts with 1.8volts. I called fosgate and said my gains are really low and they said my deck is clipping the signal casusing the amp to work hard. So I turned the gain up some and still the same problem. Anyone have any suggestion than besides makin a comment sayin Fosgate sucks or GET JL! Would the front blown tweeters effect the impedance.

 

depending on what you mean by blown...YES, the amp could get very hot. if the tweet's vc broke and is shorting itself out, then the amp will be seeing a load that it cant handle very well and should go into protection mode. the key word is "should". unfortunately, my roommate found out this weekend that a broken vc and shorted leads wont send an amp into protection mode automatically. the amp continued to send a signal to the sub and got extremely hot in the process.

my first suggestion, completely disconnect the tweets from the audio chain. see if that makes a difference. now since you are talking about comps, if the tweets were damaged, theres a chance the xover can be damaged as well and also be the cause of the overheating...

 

If you are indeed CLIPPING your amp, then your are Indeed OVERDRIVING it. It doesn't matter where your gains are set. If you still have enough signal to drive the output stage into clipping, you will have the SAME effect... It will just happen at a different spot on the volume control... but at the SAME point in actual SPL volume!

If any push-pull output stage of a power amp is driven into clipping, it will get hot because power is being dissipated across one of the active load complementary pair transistors over a MUCH longer duty cycle. This is also true of the speaker. IF the speaker (tweeter) sees a clipped square wave, it will be almost the same as if it were fed straight DC. This will almost certainly overheat the voicecoil and cause it to meltdown. Since the tweeter is smaller it will give out first.

If you ARE driving your amp into clipping... then the ONLY solution is to get more efficient speakers or a LARGER amp. Obviously your system is not giving you ENOUGH VOLUME before reaching a clipped output. You should be able to HEAR the clipping as obvious distortion. If you hear the distortion, but tend to ignore it because you just want volume, then you will continually repeat your current situation. You have to turn down the volume so that it is does not go into clipping or replace the amp and speakers with heavier duty versions. IT'S AS SIMPLE AS THAT... Now if the amp is NOT clipping... then you have some under rated speakers for the amp. How Much power is your amp TRULY rated at in RMS watts into 4 ohms?

As far as damage to the crossover... that is probably highly unlikely. As long as the components are rated for the maximum DC VOLTAGE that the amp's power supply rails are providing, then they can take the clipped signal. If you have a 50volt power supply in your amp, and only a 25volt crossover cap... then if you run the amp into clipping you could destroy the cap. But that would be a very under-rated COMPONENT system to use that low of voltage crossover cap... Look closely for any signs of BULGING caps. Especially if they are electrolytic... they would build up pressure when hot, and the rubber end would start to push out of the case. If you're high-end enough to have mylar or polyester caps... they would be really hard to blow. Chokes in the crossover are either "shunts" across the tweeter or in series with the midrange woofer. In both cases they have either a cap or a speaker in line to protect them from destructin.

The ONLY good thing about the STOCK BLOSE HEADUNIT is the fact that it has a built in "compression" circuit that "rounds" off and folds back the gain of the amp to prevent true square wave clipping. It's like when you put a pair of diodes back to back across a sinewave... they will shunt the signal into a rounded waveform. It will no longer be a true sinewave and will produce some audible distortion, but FAR LESS than fully clipped amps without this kind of circuitry. And a rounded wave will keep the duty cycle down to a reasonable time period so that both the speaker and the amp's output devices dissipate power over a much more linear range. Meaning, MORE TIME NEAR THE ZERO CROSSING POINT, giving them time to cool during each cycle.

Hope this helps. I agree with systek in that I would disconnect the tweeters and see if the amp still runs hot. If they have shorted their voice coils, then they would present a much lower impedance to the amp. If you lift them out of circuit... the amp should CRUISE... you won't hear any highs, but the midrange should sound normal and the amp should return to its normal warmth. This will then tell you that all you need to do is replace the tweets and KEEP THE VOLUME down so that the neighbors don't complain! LOL Either that or you'll need a bigger amp. AND REMEMBER... power is logarithmic. An amp with double the power will only give you 3db more SPL. This is not much. You could gain that much by possibly finding more efficient speakers. Unless you quadruple your power to give you at least 6db more headroom, then it's probably not worth your time and money to upgrade the amp. Because it sounds like you LIKE VOLUME... SO DO I... I just can't get it in my TLS But another 6db would allow you to run at your current volume without clipping and therefore keep the amp cool and the speakers from blowing. A speaker would much rather see a 100 Watt amp driven clean into them as opposed to a 50 Watt amp that is driven into severe clipping. Because if you do the math, the power that the speaker would see is actually more than the clean 100 Watt amp. Of course you always have to consider the speakers rating as well if you want to obtain your maximum volume WITHOUT smoke.

Sorry this happended to you, but if the Fosgate amp has no provision to LIMIT clipping other than a self protection overcurrent foldback circuit... then I guess I've got to say that I'm not that impressed with its design. It will protect ITSELF, but it will blow a speaker before going into its own self protect mode. Remember, even the Blose headunit protects BOTH the speaker AND the amp in its crappy sounding design. Keep in mind that the amp probably DOES RUN HOT most of the time when it has been on for 20 minutes at a good volume. Have you ever actually felt its heat back before you had trouble? The heatsink on the STOCK BLOSE runs too hot to touch after that amount of time as well. If it's not "boiling the spit" off of your finger when you touch it... that may be normal. But find out by disconnecting the blown tweeter first! The subamp won't run as hot due to the fact that there is very little bass action happening at all times. So there is more time between bass notes for everything to cool. If you can keep your fingers on the heatsink for 6-8 seconds... then yeah, that's hot, but it may still be normal. It shouldn't give you an instant blister, or go ssssppppptttt when you touch it with a wet finger either. There should also be a thermal shutdown circuit designed into any GOOD amp these days. Again, the BLOSE also has that in its design.

I've just given you the facts... the solution may be hard to decide what to do... There's ALWAYS a compromise!

GOOD LUCK!
Southbound

 

Southbound thanks for all the info, I bet that took a while to type to. I was wondering why I am having so many problems all at once. When I hade my Clarion with a millivolt out puts no problem, when I had my Alpine with 4 volts no problem and it has come down to the HU its self. I talked to the dealer here in town and said the HU is clipping its own self and is gettin a clipped single from the amp. About me playing loud music. Yes, I do, do it often but it never has any distortion and to be quite honest I didnt even know my tweeters stoped workin until I took the door panel apart to Dynamat the door. SO I checked all the tweeters and all 4 tweeters where blown. But even now with just the front mids and the rear 2 ways I dont get any distortion. The fosgate power has all the features like the thermal shutdown and protection to. The night before my tweeters where ok and the next moring it happened due to me remembering a scrachin sound on the way to the car wash, and this was at low volumes to

 

Whoo hoo My new Alpine is here. Just got the 9815 in so next week Ill take the Clarion out and put that in my RSX and the 9815 in the TL. I am waiting till next week casue thats when my Components get here to.

What are the specs that you look at to determine how clean a amp is.

 

hey dnd how much did you pay for the alpine... mine should be in next week but i went with the 7894 (like the look of it bettery than the new 9813)..

 

Well I had store credit and for a total of $700 bucks I got 2 HU's The clarion and the Alpine. I was using the Clarion in the TL till the alpine got here. It comes done to me paying 200 for the clarion and 500 for the alpine. he gave me a break on the clarion and free install. ITs the same audio place that did my faceplate. He give me free install or a great deal if its really intence. I might do a fiberglass enclourse with one Type R 12. It will be about 500 for the enclousure.

 

After hearing u talk about teh 7894 I was kinda thinking about that one to. The best he could have done on that was about $320. Shawhite have u heard of Ultimate Audio. THey do work all over FL.

 

i have never heard of ultimate audio but it sounds like he gives you some pretty fair prices... and i decided to go with the 7894 1) because i got it for $280 shipped to my door and 2) because i would have had to wait 2 weeks for the 9813... i hope to have my system halfway installed by then...

 

Shawhite are u in college or already graduated. Ultimate Audio Is gonna have there cars at the Kicker and Stinger booth at SBnationals next weekend. Post pics of your system.

So I got all my equipment and just gonna wait awhile for install.

SO now this is what I have

9815 HU

Type R components up front

Type S 6 1/2 2 ways and Alpine SPS 1015 Tweeters in the rear to. SO it kinda looks like components.

Kicker Solobaric L5 woofer

FOsgate power 550s and X.

So far my amps have been both mounted to the rightside of the trunk where the spare tire jack was and Cap mounted right below that. When trunk pops the blue neons kick in. SHould I also put blue neons on the inside of the car?