# Strange Amp behavior



## Playa123 (Jul 27, 2003)

Hey guys, before i had a problem where my old sony amp would randomly shut off. After debating, i finally got a new rockford. Now im having the same thing happen to it. With the old sony, i used to be able to unplug the fuse to the amp, and retighten all the wires(ground, power, etc.) and then it would work fine again for like 5 hours. Anyway, im thinkin now it might have something to do with how my subs are wired. They are in series, which produces 8 ohms. Could this be too much resistance? Should i try wiring them in parallel in order to get it to 2 ohm, because the Rockford spec sheet says it can handle 2 ohm, but says nothing of 8 ohm. Thanks a bunch


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## Chuck (Nov 19, 2003)

amp is overheating..


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## sr20dem0n (Mar 19, 2003)

I doubt the amp is overheating if it's stable down to 2ohm and he has an 8ohm load attached to it. Using 8ohm instead of 2ohm will only do one thing, give you less current and therefore less power. Now if you're countering this by upping the gain you might have some problems, but if you keep your gain at a reasonable level then your problem lies elsewhere. Where is your gain set currently?


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## Playa123 (Jul 27, 2003)

sr20dem0n said:


> I doubt the amp is overheating if it's stable down to 2ohm and he has an 8ohm load attached to it. Using 8ohm instead of 2ohm will only do one thing, give you less current and therefore less power. Now if you're countering this by upping the gain you might have some problems, but if you keep your gain at a reasonable level then your problem lies elsewhere. Where is your gain set currently?


My gain, as in the dial on the amp which basically means loudness lol?? Yeah its all the way up, but thats the setting it sounds the best on, i mean i dont blast it like crazy with all the loudness settings on. Rockford amps have a boost too for 6 db and 12 db and i dont use them, so idk if thats what it is....


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## sr20dem0n (Mar 19, 2003)

That's your problem, the gain is NOT a volume knob and should NOT be used like one. You're lucky you haven't blown your sub yet sending it such a distorted signal.

http://www.bcae1.com/gaincon2.htm
http://totoro.efiregate.net/HTMLPages/Tuning/GainSetting/GainSetting.htm


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## Playa123 (Jul 27, 2003)

yeah, but would that explain the AMP turning off randomly?? and what should i do instead, should i turn the gain down and put the low frequency settings higher on the crossover(in the headunit)


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## sr20dem0n (Mar 19, 2003)

yes it would explain the amp turning off randomly, it can also cause them to kick the bucket completely. Turn the gain down for starters, then if you aren't getting enough out of your sub you can turn the volume on the headunit higher (up to ~3/4 max), you can boost the low freq a little in the EQ on the headunit (not the bass boost on the amp), or you can get a more powerful amp/sub combo that actually puts out the bass you want without destroying itself in the process.


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## Sethticlees (May 30, 2002)

Playa123 said:


> They are in series, which produces 8 ohms. Could this be too much resistance? Should i try wiring them in parallel in order to get it to 2 ohm, because the Rockford spec sheet says it can handle 2 ohm, but says nothing of 8 ohm. Thanks a bunch


Why you running 8ohm?

I'd kill the gain and rewire the subs for 2ohm.
Then set the gain a tiny bit, no more than halfway. Don't over do it!

Good luck


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## SentraStyleEMW (Aug 15, 2002)

Which Fosgate amp is it that you have? If it is a mono amp, the 2 ohm wiring will be fine. But if it is a 2 ch. amp, the 2 ohm rating is if it is run in stereo (and will only be stable at a 4 ohm mono load).


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## Playa123 (Jul 27, 2003)

SentraStyleEMW said:


> Which Fosgate amp is it that you have? If it is a mono amp, the 2 ohm wiring will be fine. But if it is a 2 ch. amp, the 2 ohm rating is if it is run in stereo (and will only be stable at a 4 ohm mono load).


Yeah i have a mono amp designed for operation at 2 ohms


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## bradg (Dec 28, 2003)

the gain is a volume knob, an amp puts out the same power no matter what the gain is on. the ohm load on the amp is going to determin if you are getting full power out of the amp or not. if you are using an 8ohm load you are only using half the power the amp is supposed to be putting out. running a 4 or 2 ohm load will get you full power out of the amplifier. it sounds to me like it is possibly a sub problem. like you might have a voice coil going bad and is creating a lower ohm load while the sub is playing.


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## sr20dem0n (Mar 19, 2003)

bradg said:


> the gain is a volume knob, an amp puts out the same power no matter what the gain is on. the ohm load on the amp is going to determin if you are getting full power out of the amp or not.



do you have ANY idea what an operational amplifier is?
how about what the gain actually does?
clipping ring a bell?

please don't come here and start giving out disinformation, it looks like you need to sit down for an hour or 2 and read those links that I gave earlier.


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## Russia (Jul 24, 2003)

bradg said:


> the gain is a volume knob.


[/ban audio forum]Read, Look, Learn[/Unban Audio Forum]

That has to go into the Noob sayings thread in Off Topic  

All joking aside u need to read up man, there is a lot more for you to learn and dont give out advice ur not sure of cause it will just hurt other people.


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## bradg (Dec 28, 2003)

ok, i think i f'in know what i am talking about, maybe you need to read up. i have been doing the stuff for the last 8 years. that is what i do for a living, i own my own shop, think i have a clue, and you don't


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## sr20dem0n (Mar 19, 2003)

Well when the entire car audio world says differently than you, isn't it time to rethink your ideas?


"an amp puts out the same power no matter what the gain is on"
wtf are you smoking? everything else being equal, the only way to get louder is to increase the power correct? Just the fact that turning up the gain makes it get louder is enough to prove your statement here wrong.


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## bradg (Dec 28, 2003)

no, i am not wrong, you just said it, "Just the fact that turning up the gain makes it get louder", sounds like a volume control to me


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## sr20dem0n (Mar 19, 2003)

I guess it depends on how you look at it, the gain does behave like a volume control in that turning it up makes the output more powerful. My point is that it should not be thought of as a volume control though, because using it like one will easily destroy both your amp and sub(s).


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## bradg (Dec 28, 2003)

only if the amp is not properly matched with the subs, or subs with amp, either way you look at it.


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## sr20dem0n (Mar 19, 2003)

That doesn't really matter, if you were to turn up the gain all the way (like it seems a lot of people do) you will send the amp into massive clipping. Unless the amp only puts out a rated 50rms and your sub can take 200+ this will damage the sub, and regardless of the sub it will damage the amp.


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## bradg (Dec 28, 2003)

#2 you guys are way too fast at jumping down on someone who does not totally agree with you, or your way of thinking, i know this does not belong here, but the proper people will see it here. i thought this forum was pretty kool until now, i don't think i will use this forum any more, i don't need this kind of shit from a forum that is here to help people, not hinder or put people down. some of you guys on here are total a**h#%es. thanks to everyone for the help i have recieved on here and [email protected]#k the guys that like to put people down before they actually think about what they are saying, or think through what other people are saying. I hope all you guys learn to be nicer to people, and not put people down publicly, if you need to tell someone they are wrong, or voice your opinion about someone, use the [email protected]#%n pms. I hope all of the forum's moderators read this and forgive me for posting this here, and take notice of what is going on in their forums. Thanks to those it concerns, Later, Brad.


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## sr20dem0n (Mar 19, 2003)

How can people learn from a discussion if the entire thing is done in PMs? Are we supposed to argue and then come back here to post the results? Both people go into a debate with their own views, sometimes someone will present a compelling side and cause the other person to switch, sometimes one person might see the other person's POV and understand where they're coming from, sometimes it will just turn into a pissing contest and no one will change. No matter what the outcome is, people learn from disagreements. If your feelings get hurt when someone disagrees with you then you're right, this is not the place for you, in fact there is probably no forum that would be right for you. I'm sorry but if someone posts something I don't agree with I'll post my side and a debate ensues. I will not just sit back and let them keep saying potentially bad information. Whether what they were saying was right or wrong is decided after the debate. You'd be surprised the kind of crap that gets posted here (I'm not talking about your post, I'm talking about in general). We have to come down relatively hard to nip it at the beginning so people who don't know what's going on don't get their heads filled with bad info, if the person is actually right in what they're saying then, as long as they can defend their side, they will come out on top. If you want some examples of threads I'm talking about just look here:

http://www.nissanforums.com/showthread.php?s=&threadid=5741
http://www.nissanforums.com/showthread.php?t=31261&page=1&highlight=gear+ratio


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## Russia (Jul 24, 2003)

bradg said:


> i thought this forum was pretty kool until now, i don't think i will use this forum any more.


Damn...Im def. gonna lose some sleep over that one Brad. Another way we look at someone is when we say they are wrong whether they accept being wrong or flip the fuck out like a 5 y/o kid. Dude to you its a volume knob, but to someone reading this forum with their first Amp and trying to tune it and they know nothing about it but want big sound its a fucked up amp/subs/mad loss of $. Either restate...rethink...but def. relax.


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## Misanthrope1144 (Jan 6, 2004)

lol , say it loud and say it proud , russia. :thumbup:


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## Playa123 (Jul 27, 2003)

Misanthrope1144 said:


> lol , say it loud and say it proud , russia. :thumbup:


I love it, i feel like the girl a group of friends are fighting over. Anyway, either way this didnt really help me, but basically this is the problem now. I tried reconfiguring the amp so that its gain isnt as high and raised the bass a little on the headunit. It still did the same thing tho. Its not the subs that cant handle it, its the AMP thats turning off after listening for some time. Now i have the amp powering just ONE subwoofer, and it seems to be going fine, but im missing that extra kick. Anyone have any other suggestions, or how to check what could be wrong?? Lol, lets not lose any more members with this discussion.... :cheers:


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## sr20dem0n (Mar 19, 2003)

did you try setting the gain on the amp using that 2nd link I gave?
that's the proper way to set the gain, it will make sure you aren't clipping the signal and putting undue stress on the amp (read: heat)


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## Playa123 (Jul 27, 2003)

sr20dem0n said:


> did you try setting the gain on the amp using that 2nd link I gave?
> that's the proper way to set the gain, it will make sure you aren't clipping the signal and putting undue stress on the amp (read: heat)


Yeah i set the gain the right way, but it still randomly shuts off but only when i have 2 subs wired together. Im gonna try it one more time before i keep looking for other answers


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## Punkrocka436 (Jul 8, 2003)

This doesnt even deserve a response...bradg, you sir, are a moron


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## sr20dem0n (Mar 19, 2003)

have you tried rewiring it for 2ohm?
having it at 8ohm shouldn't cause any problems at all, but you still might be clipping the signal by boosting it at the headunit.


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## Playa123 (Jul 27, 2003)

well yeah, i just rewired it to 2 ohm, well see how it holds out, i set the gain down and all just like you said, but if it doesnt hold out i might need to look into new subs


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## sr20dem0n (Mar 19, 2003)

yeah, if it still cuts out you should check your wiring (fuses, ground, remote, etc) to make sure everything is secure. My amp was acting up a while ago, I would turn on the car and it would immediately go into protection. Turns out it was the fuse, it wasn't blown and it still looked good from the outside, but there must have been a bad connection at one end because it wasn't passing enough current to keep the voltage up.


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## Playa123 (Jul 27, 2003)

sr20dem0n said:


> yeah, if it still cuts out you should check your wiring (fuses, ground, remote, etc) to make sure everything is secure. My amp was acting up a while ago, I would turn on the car and it would immediately go into protection. Turns out it was the fuse, it wasn't blown and it still looked good from the outside, but there must have been a bad connection at one end because it wasn't passing enough current to keep the voltage up.


Yeah maybe it could be a fuse, ill test out putting another bigger one in there, but its not like that where it Suddently shuts off after the car comes on. It plays for a while and then turns off suddenly, like it takes a little bit for it to overheat... I rewired it and it still does that.. Somone said something about a bad voicecoil, How could i check/replace that?


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## sr20dem0n (Mar 19, 2003)

any chance you have a multimeter?
if so it's very easy, if not then I don't really know how to check that


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## Playa123 (Jul 27, 2003)

sr20dem0n said:


> any chance you have a multimeter?
> if so it's very easy, if not then I don't really know how to check that


Yeah i have a multimeter. What else hsould i check except for the fuse, i heard you can check the subs and even the amp with the multimeter to check for problems, can someone please tell me how to check em to see its in working order. Thanks a lot for the help so far :woowoo:


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## sr20dem0n (Mar 19, 2003)

just go to "ohm" mode, and test it at the + and - terminals you run to your amp (make sure you disconnect the sub from the amp before testing or it will throw it off). If you have it wired for 2ohm then it should read about 1.6ohm, if you have it wired for 8ohm then it should read about 6.6ohm. If it's dramatically lower than these and you're positive the wires going to the sub aren't shorted, then you most likely have a blown coil and it's shorting out inside the sub.


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## Playa123 (Jul 27, 2003)

sr20dem0n said:


> just go to "ohm" mode, and test it at the + and - terminals you run to your amp (make sure you disconnect the sub from the amp before testing or it will throw it off). If you have it wired for 2ohm then it should read about 1.6ohm, if you have it wired for 8ohm then it should read about 6.6ohm. If it's dramatically lower than these and you're positive the wires going to the sub aren't shorted, then you most likely have a blown coil and it's shorting out inside the sub.


Well i checked and that doesnt seem to be the problem. The ohms on each sub are approxiamately 3.2-3.3 ohms each, and the same applies at the terminals. I also checked the fuse, it was good, and i checked the power terminals on the amp which were also receiving the proper 12 volts. IDK what it can be, i had my amp hooked up to my subs PERFECTLY for about 5 months, i mean i blasted that thing sometimes and now when i do that it seems to short out/ overheat/ or go into protection mode. What could've changed?


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## Russia (Jul 24, 2003)

My only left guess would be that after the heavy pushing it mayb its jus the age and the use thats doing it....I would hope not because thats only 5 months, but I ran out of ideas.


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## sr20dem0n (Mar 19, 2003)

Russia said:


> My only left guess would be that after the heavy pushing it mayb its jus the age and the use thats doing it....I would hope not because thats only 5 months, but I ran out of ideas.



me too, have you tried calling the manufacturer?


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