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View Full Version : Dead speakers, need help.



dtavano
06-20-2007, 03:19 PM
Well ok. Yesterday my amp cut out while I was riding to work. When I got off I powered it up again and had sound only from my right components. Fifteen minutes of music caused the right midwoofer to go out, so I am stuck with just the highs from the tweeters. I've measured the amp with my voltmeter and its output voltage is correct.
Here's the weird thing. When I removed my panels my midwoofers were "stuck" in their position and it required a bit of force on my part to unstick the cone from the motor I'm guessing. The speakers are dead. When I send it a 1khz tone the volume is wavering and breaks up at my normal listening volume(loud, teehee.) Eventually either the amp shuts off and the diagnostic light turns on, or the driver begins to smoke. I sent it a 100Hz tone and all I get is a bzzzz sound and the amp quickly goes off into diagnostic error mode. Obviously these speakers are dead, that is not too big of a problem because they only cost me a hundred bucks shipped from woofersetc. My parents *****ing and my lack of installation knowledge caused me to get 5.25" drivers so I'm not really too angry, I really want 6.5's heh. But really, I'd like to know what you think caused this? Could it be the small amount of water(I'm talking about just several droplets on the back of the magnet and in the general area near where the speaker is mounted?) Or do you think I was just overpowering the speakers and they naturally died? I mean, if they died due to being overpowered, I find it incredibly difficult that they would do so so close in time to one another. Ive been running these speakers for 2 months and find it hard to believe that if they were to die without outside influence other than the signal itself, they would die at times not so soon together.
If you think it's the water, would it make sense for me to go with a different type of cone on my next pair of speakers. They were CDT-s50 and had treated paper cones. Is this not durable enough to survive in the humid environment of houston, texas? I'm just a bit confused and don't want the same thing to happen when I replace the speakers.

Thanks,
Dan

PS:
I might as well get this in this thread so I don't have to post another. When I do replace these speakers, I need some help on ideas to improve my midbass. I'd like a more smooth transition from subbass to midbass in my car. I am running 2 12w3v3 @ 26Hz with a JL 500/1. I have a cadence z800 that can put 2 x 125 watts @ 4ohms or 2 x 225 watts @ 2ohms. If I were to run a 3-way system, could I run the midbass driver in parallel to the midwoofer and tweeter(in series I presume?) so the amp sees a 2ohm load and splits the 225watts between the midbass and the midwoofer + tweeter? Or does it not work like that? Would I have to go with 3-way components to even have a chance of getting a somewhat even and linear curve between sub and midbass? Should I just build a sealed box and cross my subs higher? I have them at ~85Hz at 24dB/octave with my (now dead)5.25" drivers. Sorry for all the questions!

PPS:
Oh yeah. I would like to say that I would prefer to have my bass guitar sounding like it is coming from the front of the soundstage. As soon as I cross my subs higher than 85Hz @ 24db/oct it seems as if the bass guitar no longer has that presence in the front. This seems weird because I was under the impression that sound <250Hz is omnidirectional. arggg

crow
06-20-2007, 07:25 PM
For the first part, I haven't a clue.

For adding midbass speakers, I think you would be better off purchasing a separate amp for them. That way you can highpass the midrange and tweeter set with the amp's crossover to roll off where the midbass picks up.

For water issues, a foam speaker cup can create a sort of canopy over the speaker basket and magnet. You cut out the back and bottom of the cup so the speaker can still use the space in the door. Crutchfield sells them pretty reasonable.

The thing that improved midbass tremendously in my truck was adding sound deadening to the door panels. I deadened around the outer door panel and the area around the speaker and there was a noticable improvement in midbass. My next project is to add another layer and seal the door panel completely.

dtavano
06-21-2007, 11:57 AM
I have already sound deadened my door panels, both inner and outer.

How does the impedance work with component speakers? You can have a 3-way system that's 4ohms, but what if I had a 2-way @ 4ohms and added a midbass driver which should be @ 4ohms... so if I ran them in parallel would I not get a final impedance of 2ohms or does it not work like that? If it doesn't please explain to me how it works :).

Also, would it sound horrible if a midbass driver didn't feed into the cabin and was fired right at the door panel with no exit? At this point of time I can not modify the door panels to make a second grille for a speaker. If not, than I guess I could fabricate some sort of ugly kick panel baffle/mount and put the midrange there, and place the midbass drivers in the doors.

If anyones ever heard of a speaker getting stuck as I described in my original post, please let me know.

crow
06-21-2007, 08:11 PM
It would be a 2 ohm load. The problem is that you will want to be able to lowpass the midbass and highpass the midrange for a good transition between the two. With only two channels of amplification you would need additional passive crossovers to make the transition between the midbass and midrange. It's not impossible to accomplish but it would be tricky.

If modding the door extensively is a problem and you want three way, you might look into some of the three way sets with a dome midrange. I think DLS and Eclipse both use domes in some of their component sets with crossovers designed for for three way use.

dtavano
06-22-2007, 03:54 AM
Could I not use the 3-way passive crossover provided by the components, or will my results be not that good and far inferior to an active setup? I think the main crossover concern would be the highpass going to the midbass driver so I could get it to mix well with my sub. I can use the active crossover from the preamp of my 500/1 to highpass my component amplifier either at 12 or 24dB/oct. Would the passive crossover that comes with the set be adequate for the lowpass on midbass, bandpass on midrange and highpass on the tweets(with attenuation control) with the highpass of midbass being the 500/1 as stated before?

Also, I can put the midrange drivers in my kickpanels. I'm guessing it should be run IB. But, the 6.5" midbass driver will be feeding into the car through the stock grill for 5.25" speakers. Will this have a large effect on the sound?

Thanks for the help, crow :).

PS: Still not understanding the whole impedance thing with component speakers. Ok, with a 2-way component you typically have a 4ohm impedance. Now, in a standard passive crossover setup, how do they get this impedance? Is the tweeter being run in parallel or in series to the midrange driver? I also notice that the 3-way systems also have an impedance of 4ohms. So... where do you get that 4ohms from? I'm also not understanding mathematically, how by putting the midbass driver in parallel you lower your impedance to 2ohms. Like, when given the impedance 4ohms for a 3way system, how is that split up between the 3 drivers? I'm quite confused and I'm sure how I've written this out is confusing as well.

crow
06-22-2007, 08:48 PM
Could I not use the 3-way passive crossover provided by the components, or will my results be not that good and far inferior to an active setup? I think the main crossover concern would be the highpass going to the midbass driver so I could get it to mix well with my sub. I can use the active crossover from the preamp of my 500/1 to highpass my component amplifier either at 12 or 24dB/oct. Would the passive crossover that comes with the set be adequate for the lowpass on midbass, bandpass on midrange and highpass on the tweets(with attenuation control) with the highpass of midbass being the 500/1 as stated before?

The passive crossovers provided with two way or three way sets are designed to work with those drivers. You can use the crossover on the amplifier to highpass the component set to blend with your sub and you'll be set. There are many excellent two way component sets available. I would only look at three ways if you have the time to test out different driver locations to get the aiming of the drivers correct for your car.


Also, I can put the midrange drivers in my kickpanels. I'm guessing it should be run IB. But, the 6.5" midbass driver will be feeding into the car through the stock grill for 5.25" speakers. Will this have a large effect on the sound?

It would really depend on how much restriction the stock grill has. Unless it is significant, the 6.5's will probably be ok.


PS: Still not understanding the whole impedance thing with component speakers. Ok, with a 2-way component you typically have a 4ohm impedance. Now, in a standard passive crossover setup, how do they get this impedance? Is the tweeter being run in parallel or in series to the midrange driver? I also notice that the 3-way systems also have an impedance of 4ohms. So... where do you get that 4ohms from? I'm also not understanding mathematically, how by putting the midbass driver in parallel you lower your impedance to 2ohms. Like, when given the impedance 4ohms for a 3way system, how is that split up between the 3 drivers? I'm quite confused and I'm sure how I've written this out is confusing as well.

I'm not sure :uhoh:. Best explanation I've heard is that the impedance of a speaker is not constant across the range of frequencies it plays. The crossover is designed to dictate which frequencies are reproduced by each driver in the system and maintains a nominal impedance on the system that can be matched to an amplifiers abilities. Don't hold me to that as I find the whole thing confusing as well:D .

buildmeabox
06-22-2007, 10:29 PM
I'm confused, but I can answer the stuck speaker issue and how the 2-way/3-way systems work.
1) ferrofluid in the magnetic gap can cause the voice coil to seize.

2)Because the impedance of the speaker circuit, tweeter-midrange-midbass, do not play the same frequencies the amp will see electrically the nominal impedance of each driver in the circuit. Here's an example- two four ohm SVC subs in parallel equal 2 ohms when wired to an amp, why? Because they will play the same frequencies. But in a 2-way or 3-way system each driver plays a different set of frequencys' and as long as each driver in the circuit does not play in the same frequence range as the other drivers the amp will see electrically the nominal impedance of each driver in the circuit.

So as long as all your drivers in the circuit are equal to each other then you shouldn't have a problem. If you need help with your setup or any ??? pm me, since I live in H-town I'm only a hop and a skip away plus I have some old school Orion XTR x-overs you can have if you want, they might help you setup. Good luck

dtavano
06-23-2007, 02:03 AM
I'm confused, but I can answer the stuck speaker issue and how the 2-way/3-way systems work.
1) ferrofluid in the magnetic gap can cause the voice coil to seize.

Is that water? To me it sounds as if the cone is just disconnected from the voice coil. But all I know about car audio is what I've read and what I've done to my car. To me the midbass sounded very weak despite sound deadening my doors and sticking eggshell foam behind the driver. Although I was using the passive crossover, it seemed absolutely necessary to put on the highpass @ ~67Hz @ 24db/oct from my 500/1 preamp. The lowpass for my subs was incredibly delicate, for there to be a somewhat decent rolloff from subs to comps I had to set it at ~85Hz @ 24db/oct. If I low passed it any lower the volume change from sub to midbass was much to noticable. Anything past 85Hz and it no longer sounded like the bass guitar or kick drums were coming from the front of me.
Perhaps I should just get a 2-way system. Should I expect a significant increase of midbass from 5.25" to 6.5"? Bleh, I'm just sick of my friends bmw with no aftermarket work done on it having nicer and cleaner sounding bass guitar. Oh well.

patrick1202
06-23-2007, 02:14 AM
it locked up you prolly did somethin wrong lol idk what were your gains on i doubt it was water highly doubt it especially being deadner