elevario

First off I'd like to tell you guys about my system. It's not anything extroardinary but I like it. I have a lightning audio s5.700 amp that is five channels and delivers up to 100w to the front speakers, 75w to each of the rears and 350 to the sub. Those are all max power not rms. So it's not that big but sounds good to me. Now I hooked up the amp and the sub and the sub works with no problems. Then when I hook up the positive and negative wires from each speaker to the amp (and the 2 sets of rca's) the fuse on the back of my cd player blows. This sucks because I really want to hear all my speakers amplified but whenever I hook them up the fuse on the player blows. Does anyone know what I could do to fix this? THe fuse on the back is only 10. So should I throw in a 15 or 20? Or would that be bad? I'm sorry, I'm really new to the car audio thing and would really appreciate any feedback from anyone. Thanks! Eric

tamu130

is it on the accessory wire or constant? did you wire the amp turnon from the accessory wire into the head unit or to the blue remote turnon wire coming from the hu? you really havent given much info but i will try to help you if i can.

jacob

elevario

I wired it onto the headunit remote turn on. Should I do it different?

tamu130

no, it is suppose to go from the blue remote wire and if i am understanding you right, it does so you are right there. did you wire the amp constant from the battery directly?

these are the kind of situations you wish you were there for.

elevario

The power wire is connected to the battery thru a battery clamp and the remote wire is wired from the amp, onto the headunit remote turn on wire (blue with white stripe, it says rem amp 0.3A or something like that) The fuse blows right when I turn the key on. See the sub works fine without the other speakers hooked up.

tamu130

that seems strange. . maybe that wire is bad or there is a short in the system. dont think that would be it, but ya never know. is there a solid blue one (i think its used for the p. ant). if so, you might try that one. other than that, im stumped. you also might try the 15 amp fuse. wouldnt think that would help, but ya never know. good luck either way.

AJ_92RS

That is strange.

I've had something similar happen, but it was with a seperate amp for the fronts. Come to find out the remote had been pinched under the amp when I mounted it and it was shorting out.

I'm gonna guess there's a similar problem with yours. First thing I'd check is the RCA's. Make sure they're not being pinched or that they're not touching any metal at the back of the CD player, and where they connect to the amp.

Make sure that NONE of the speaker wires are grounding out also. I know you'd think that the amps fuse would blow first, but stranger things have happened.

elevario

Well thanks a bunch for the help guys! It's dark now and I ran out of fuses so this will have to wait till morning. THis sucks, I don't want to have to look at all the wiring again! It took me like 2 days to finish the stupid wiring! Well at least my sub works, and it sounds damn good for only like 250 watts going to it! It's a Rockford HE. Not anything special but more than enough bass for me!

DISTURBthePEACE

The sub works but the rest doesnt? Did you wire the components to the amp only or did you wire to the wires running to your headunit AND your amp? That might cause it to blow the fuse...Just throwin out ideas, I really don't know. If your runnin the highs off the amp, the only wires you need connected behind the cd player is the 12v constant, accessory, ground, and rem amp, no need to connect the speakers to the headunit if your running them off an amp, the RCA's will cary the music signal to the amp and the amp will do the rest.

elevario

Holy crap are you serious?! See my friend told me to splice into the wires that come from the headunit! So are you telling me that all I have to do is run the speaker wire from the amp straight into the speakers? Is this how you're supposed to do it? because if that's it, I will do that and be done with it! All the wires are ran already and all I have to do is connect those wires to the speakers? So what will happen with the controls for bass, treble, balance and fade from the cd player? Will they still work? What about the volume? Do the rca's just make the amp an extension of the cd player, for example does the volume and everything still work but all the power is controlled by the amp? Please answer back, i would like to get all this done! Thanks for the input! Eric

tamu130

ah man, no wonder. you are lucky if you didnt ruin your hu. i would never have even thought of that without seeing it. your highs should be wired from the amp and only the amp. the rcas pretty much tells the amp what the music is and then the amp amplifies the signal to the speakers. if all of your speakers are run off that amp, then none of the speaker wires from the back of the hu should be connected to anything.

elevario

Man you guys are the greatest!! I'm giving all you guys a big And this is me Now I only have a couple more questions. When the cd player first turns on, (like when I first turn the key to the car) I guess when the amp gets power it sends a little surge to the sub with results in a very quiet hit of bass. Is this normal? And also my sub doesn't play when the radio is on. Just with the cd player. Is there any way I can fix this? Thanks!

AJ_92RS

I guess DISTURBthePEACE saw what I didn't want to.

I thought I read that, but I said to myself "No. He means something else."

Oh well. Glad one of us was able to help.

The thump is because (and try not to take offense) you have a cheap amp. The capacitors inside are getting charged as soon as you turn the amp on. Every electrical current has a frequency that it operates at. 60hz is about the norm, so guess what? The sub will reproduce the sound the loudest.

Better amps have devices in them that will turn on the amp gradually so you don't get that "thump".

As far as the sub only working with the CD player, it could just be the HU. If you have the “Loud” button on in CD mode, some HU’s will turn it off when switching to the radio. You may have to turn it on while the radio’s on.

It could just be the radio station also. A CD has much better s/n ratio characteristics than a radio frequency, so when you change it to a radio station, the sub just isn’t getting the intense bass it does with a CD.

What HU do you have?

elevario

It's a Sony Xplode CA860x. It's that one with no buttons, just all display and the only way you can change things is thru one of the two remotes. I do have the loud button on the cd player. So when I switch to radio the sub completely turns off. I know this because I went to the back of my car and put my hand on the sub to check and it wasn't even moving. Oh well. That thump though, you say it's just because of the cheap amp? So that is normal and won't hurt anything? You know that just sucks because when I was looking for a nice 5 channel amp and found this one, the guy had lots of great things to say about it. Like lightning audio is owned by rockford fosgate so it makes REALLY great amps for the money. That sucks. Maybe I'll try and find a different 5 channel amp after a while. Well anyways, this is what my cd player looks like. It actually looks a lot better than this pic makes it look.

Eric86TA

I think you are thinking about your home electricity. Your home works on AC at 60Hz. Your car works on DC which has no frequency. It amazes me that car audio people don't know this. I won a T-shirt at the DBdrag World Finals when I was in a crowd full of installers and they gave a T-shirt from Alma Gates away to anyone who knew what frequency DC was. I was the only one who knew.

AJ_92RS

No joke Sherlock...

Obviously you're forgetting that the amplifier switches the DC current to AC current. I has to, otherwise there would be no music coming out.

And you won a shirt? WOW!!!

I'm impressed.

Jim85IROC

iTrader: (2)

:sillylol: :sillylol: :sillylol: :sillylol: :sillylol: :sillylol:

tamu130

i was thinking that same thing. hard to make the speaker play w/o the ac current. but i dont think this should be apart of this topic. it doesnt really help to solve his problem.

elevario

Hi guys, everything is finally fixed! I just want to thank all of you for your help. The thing that was blowing fuses was that I didn't have the speaker wire going from the speaker straight back to the amp. I had it going to the amp and to the headunit. So I fixed it and finally everything is working! Now just to get rid of those rattles!!

tamu130

good luck with the rattles. thats a never ending story. congrats on fixing your problem.

Thirim

if you have a power antenna and your deck uses the blue (power amp turn on) wire as the power antenna wire. as mine does. You should put that on a relay. My deck (pioneer 9400) supports 12v 300mA on my blue wire (amp/antenna).. All I did was run a wire from the battery (fuse it at the batt) to a relay i mounted on the engine fire wall.. took 2 wires from there into the dash. (one for the trigger .. wire coming from deck) and the other for the output .. wire going to amp and antenna. to over complicate it I put the wire going to the antenna on a switch and the amp wire right back to the amp.. that way the stupid ant isn't up when i'm playing a cd.

where i'm going with this.. deck supports 300mA.. relay draws 150-250 ish .. and you would have 2.. the ant has its own relay.. plus whatever the amp draws.. i played it safe. plus I had 3 amps

NEEDAZ

Eric86TA and AJ_92rs, your both a little right. The amp takes the 12Vdc in and powers the output stage with something like 30V-65Vdc. To do that it takes the DC and tuns it into AC, But NOT at 60Hz. Its more like 30,000Hz. I think that is where the confusion came in. That and the “Every electrical current has a frequency that it operates at. 60hz is about the norm” comment, because DC (direct current) has no frequency. That little hit of bass is called DC thump. It happens when the amp first gets power and the bias is stabilizing. Has nothing to do with the type of current or its frequency.

Eric86TA

This is exactly what I am talking about. If you know what you are talking about why would you make a statement like that. I guess AJ would have been scratching his a$$ with the rest of them while I got my T-shirt. And I'm sure he still wouldn't be impressed. No Joke AJ:sillylol:

Eric86TA

Exactly when does the amp convert the DC to AC? Jim can answer this also. I would really like to know. The music coming out of the amp is not AC. An AC signal is a pure sinusoid. The music coming out is just a signal with frequency from 20 to 20,000 hz. The DC power input amplifies the small signal that is coming into the amplifier. Why would you take the effort to convert a DC signal to AC? It is actually difficult to reproduce a pure sinusoidal signal.

AJ_92RS

You really should have quit while you're ahead.

In order to move a speaker back AND forth there has to be both a positive AND negative current alteration. If there was no positive and negative current alternation then the sub would only move in one direction, then sit there waiting for either the current to stop, or for the negative alteration. That's why AC stands for Alternating Current!!

And to NEEDAZ,

I did say 60 hz being the norm for a reason. That's why you hear it through the subs. If the noise was produced at 30,000 Hz, then it would go through the tweeters, and no human would hear it. So the frequency DOES have an effect.

The noise is actually produced whenever the capacitors first charge up. The speaker creates a closed loop for the current to flow through. That's why he hears it. Same as if you discharge a capacitor with a screwdriver. The only reason you hear it *SNAP* is because of the frequency of the current passing through the air.

Frequency has everything to do with everything we hear, and even some things we DON'T hear. So, do you want to explain how frequency doesn't matter?

Next you'll be trying to talk me into buying a Rockwood amp, or worse yet, A FORD MUSTANG!!!

Eric86TA

No one said there is no frequency. What I said is that there is no AC current. AC is alternating at pure sinusoidal rate (maybe you don't understand trig). While a music signal has frequency that is continually changing, it is not an AC signal. I guess if you just listened to one frequency all the time you could call it AC. I personally don't listen to burp tracks all the time. I suggest a Signals and Linear Systems class. My whole point goes back to your orignal statement when you said that the caps were being charged and that the current has a frequency. Wrong. The caps are being charged by a DC power signal the has no frequency not by an AC power signal. I'm tired of discussing this so I guess you can just go and listen to your 60Hz amplifier :rockon:

tamu130

i think this post has gotten a little ridulus. i completely lost what you guys were saying. partially because i dont know what yall are talking about, and partially because IT DOESNT MATTER. knowing any of this stuff you guys are talking about really does not help you do anything with car audio. i personally dont think either of you are completely right, but of course you'll both probably disagree w/ me. how bout we just forget about this topic and get on w/ our lifes since elevario has solved his problem. if yall are gonna argue, take it to pms or emails.

NEEDAZ

Eric86TA and AJ_92RS if you want to discus this more e-mail me. n3nxl@yahoo.com I’d be more then happy to explain every thing I said, as long as we can keep things civil. But like tamu130 pointed out this is way off the topic of the original post and some people don’t like to see any more information then absolutely necessary. Something about not wanting to learn.

Jim85IROC

iTrader: (2)

I really wanted to stay out of this, but since I was asked...

The signal being sent to a speaker is absolutely, without a doubt, an AC signal, and it's all sinusoidal. Just because it doesn't sound like a test tone doesn't mean it's not a sinusoid. It's just a very complex signal that's made up of a virtually infinate number of sine waves.

Eric, to answer your question, the amp converts to AC immediately. The amp needs to provide an AC signal to the transistors that do the actual amplification, so right at the input stage of the amplifier the DC power is converted to AC and stepped up to whatever voltage has been implimented for that design.

joezero

Jim, I have to disagree with you on one point.
The amp doesn't convert to AC immediately. The DC is present on one of the three pins on the transistor. (you'll have to forgive me as it's late and been a long week, so no big tech terms tonite) The the audio signal (AC wave) from the pre-amp section of the amplifier is sent to another pin. Then, the transistor uses the DC power and turns it into AC and sends it out the emmiter. If the amp used AC power instead of DC, you'd get nothing but static. The voltage is also what is used to determine the amplitude of the sound wave generate by the speaker. So at the lowest setting the amp may go from 0v to 15v and at the highest will peak well over 50v. Here's a link to a website which gives many more specifics on how amplifiers work.
http://electronics.howstuffworks.com/amplifier2.htm

DISTURBthePEACE

I was right? All right! sorry, I just got back from mexico so I am a little behind on my posts. Glad I could help.

elevario

Yes you were! Thanks a bunch! I finally got rid of a crap load of rattles and it sounds REALLY good! I never realized the Sublime songs "What I got" and "April 26 1992" had soooo much bass in it! I have another question though. Does anyone know what speaker I can run to get some really good mid bass? I think my rockford 6x9's are blown because all they do is pop when it gets a good hit. Does anyone have any good ideas?

Jim85IROC

iTrader: (2)

In virtually all amps, there is a direct line to the power supply from the input feed, usually with nothing more than the power switch or a relay controlled by the power switch in its path. The various AC and DC voltages necessary for that design are converted from the original DC signal, and distributed to where they need to go. I never suggested that all of the power was converted to AC, but the power conversion is usually one of the first circuits that you find in the electrical path.

Keep in mind that the link you posted shows a home amp. Although it's 99% the same, the power supply is very different. In a home amp you're pulling AC out of the wall, so the main power being fed to the FETs is just passed through a step-up transformer. DC voltage is created to power the electronics. In your typical car amp, you're starting with 14VDC, so you've got to convert it to AC for the FETs. You've also got to drop the DC voltage for a lot of the circuitry.