I need an expert opinion on amp install
 

Ok, I have posted before about a Refurb Kicker SX700.5 that I bought and arrived DOA(started smoking on start up). Well, yesterday I got the replacement. This unit wont work for me either. Here is the symptoms (this assumes all gains etc. are in the lowest setting):

When the unit is powered (B+, REM, GND) with nothing else connected it powers on
With the speaker outputs connected (all four channels and sub) the unit stays powered on
When you connect the high level inputs [HLI] the unit goes into protect unless the volume on the HU is set to lowest
With the HLIs removed and an ipod connected to amp1 preamp ins (per kicker instructions) the unit plays BUT if you adjust the gains on amp1 or 2 even slightly the unit goes into protect. The sub channel (amp3) gain and boost can be adjusted quite a bit before the unit goes into protect.

This is how it is connected:

4ga B+ and GND run directly to the positive and negative terminals on the battery. Each cable is less than 5 feet long. B+ is fused with an 80amp Maxi. (kicker calls for 90a which does not exist).
The 4ga cable is actually battery cable from checker auto with pressed on fittings and thin strand wire.
The REM wire is run from an ACC on fuse in the under seat fuse box (18ga wire)
The front channels from the deck are connected to amp1 rear to amp2

Can anybody come up with ideas why this is happening or ways to test for problems? It took a month to get my replacement from this horrible company and I've got a claim in with paypal but Kicker wants me to send it to them for them to fix. I just dont know what to do.

I appreciate any suggestions.

what head unit are you using?

you GND does not need to run to the battery, ( i think thats how i read it) those are the main things that stick out to me.

GND to battery won't affect anything. The best place you can go actually. But the length of GND run you have is a bit long though. try taking it to a closer point to the amp to see if any different.

To me it sounds like you have a power issue though to the amp. This 4ga wire your running, is it alot of smaller wire bundled into insulation or larger coper runs inside the insulation? Not that it should make a difference, but im curious i guess. If your GND and power wire are all good.....your fighting junk amps im sorry to say. i have seen them on ebay and they do sell cheap...but it makes you wonder were all the refurbs are coming from. i mean, they are refurb in quantity for a reason. i had thought of buying one before, but the sheer quantity of them on there for sale made me skeptical to buy one in case of problems.

My suggestion, find a small junk amp..something if it smokes you dont care..hit a pawn shop.....pickup a $10-15 amp..or garage sale..... just something cheap....hook it up to your cable runs and see what it does.....

1st I am using the factory head unit and thus am required to use the high level inputs.

2nd the power wiring is 4ga fine stranded like you would find in any amp install kit. The only difference is that it has a high temp rating for the insulation. The battery is under the seat very close to the amp so I see no reason not to run the GND back to NEG on the battery. The run is less than 5 feet. The only oddball in this set up is that on the power lead I used about 4 feet of 4ga thick strand (home electrical grade) copper wiring that is commonly used for grounding a house. This goes from the fuse block to the amp. From the fuse block to the battery I used the previously mentioned automotive grade cable with the integrated ring terminal. I know its cheap but thats why i buy refurb amps in the first place :lol: .

I'm going to just get my money back I think. Unless you guys really think there is a realistic possiblility that its my wiring. The only difference with house grade 4ga and auto grade is the finer strand wire which could be considered more dense. I know it sounds ghetto but in reality it is very neat and orderly.

before you send the amp back, install a piece of standard auto battery cable if need be from local auto store..or a piece of auto 4ga from a friend or something and replace the wire from the fuse to the amp. put the amp in back seat if need be to test this if can't find a piece long enough.

im not going to say its the house wiring that is your problem, but i am curious now if it can cause an issue. my own concern would be the insulation on the wiring.... but im no expert on house wiring by any means. take out that variable and let us know what happens?

are you sure you have no bad wiring to speakers causing a short of some sort in them? what are you running speaker wise from the amp? aftermarket...stock...? what ohm are the speakers being ran on it?

2 things
First, the house wiring. Get to a finer multi-stranded wire.
Second, the connectors to the wire. Make sure you have GOOD, SOLID connections. If you can, flood-fill the connector to ensure each and every nook is filled and making contact. No matter how big the cable is, if the connector end is not on good, you'll have problems.

It sounds like theres an internal short in the amp. When there is no input signal the amp is probably drawing a lot of amperage, but not enough for it to go into protect, but when theres any input signal it sends voltage to the speaker which overloads the amp. Measure your speaker leads with an ohmmeter to make sure they arent shorted out. Sounds like am amp defect.

Well just for the heck of it I'll install some fine-strand wire tomarrow and see if it makes a difference.

When the amp is plugged in it sucks the battery voltage down pretty quickly. Even with the car running, the volt-meter on the dash is well under 12v, but jumps to 14 when the amp is unplugged. I checked the speakers for a short by touching each pair of leads to the amp outputs one at a time and none put the amp into protect (this is with no input). Also the speakers (which are aftermarket BTW) function without issue when connected to the HU directly.

Thanks for the insights I'm just gonna get my money back but I want to rule out any issue that could cause a problem with a new amp and i'm just curious.

If its drawing a lot of power when its just plugged in then its definately faulty. No question. Get your money back.

yes, it is sounding like a faulty amp, but as you said, please try replacing that wire before you do....i think we are all curious now.

hearing the part on the voltage was good info to have.

That is not right. No amp should do that. You definitely have a problem in the amp itself. Get your money back.

Test for DC voltage on the speaker outputs of the amplifier. Use any DC voltmeter, set to a range of about 50 volts. If the meter pins negative just reverse the tester leads on the speaker outputs.

A blown amp is pretty easy to diagnose, you'll usually get a power supply rail at the speaker output.

Also, you said you're using high-level inputs on your amp, so you're running the wires that used to feed your factory speakers to the amp's high-level inputs, is that correct?

Some of the factory systems use a common signal ground, while some amplifiers may require an isolated signal ground. In order to convert the factory common to isolated, you can use a device like this:
http://www.sonicelectronix.com/item_...OEM-GM21C.html
(There are different models depending on what factory head unit your car has.) An additional advantage of using this type of adapter is that it will supply a line-level signal source to your amplifier.

Can you possibly use any small source, such as an iPod or walkman-style CD player as an input to the amp on the line-level inputs of the amp? That would be a better indicator of whether your amp has a problem, or whether you just goofed the connections.

I personally think the advice to change your power cables to the amplifier, while well-intentioned, have nothing to do with your problem.

I did. It works ok off the RCA input from my Ipod but still goes into protect when i touch the gains.

Also, I spliced into my old speaker leads so i have a wire coming from and one going back to each speaker.

Does anyone know what system, isolated or common, the 01 base model stereo with cd/tape uses?

Is there any range on your gains where the amp does not go into protect? All the gains are for is to match the level of the input signal to the input stage of your amp. Your gains probably have significant gain, and if you feed a line level signal (on the order of 1 to 3 volts peak-to-peak) to it and turn up your gains, it's probably normal to be able to trigger it into protection. You just need to find a range that works correctly, then dial them in to the higher end of that range.

You should still test the speaker output terminals on the amplifier for DC voltage. If it's working, it should have zero across each terminal pair when you have the volume turned all the way down. If you have significant DC voltage, then you have a bad amp.

I think if you're going to run an aftermarket amplifier with your stock headunit, you'll need the adapter that I linked to earlier. That will maintain your stock wiring harness but give you line level outputs tapped off your head unit. You'll need to run RCA's from that to your amp. It's okay to use your stock speakers with your amp (if you must), if you already cut the wires, just put some tape or crimp one half of a wiresplice butt-connector on the ends that come from the head unit so they don't short out on any of the car body. (Or with each other. Do NOT connect the loose ends together!!)

But I think there's basic differences between your stock speaker output and the inputs on your amplifier. Your amp no doubt has a single-ended input referenced to ground. The output of your stock car head unit may be a bridged differential pair where the + and - lines of each speaker pair are a signal and inverted signal pair, rather than a signal and ground for each pair.

Presuming that's the case, you'll need the PAC adapter to run an aftermarket amplifier with your stock head unit. Fortunately, they're relatively inexpensive at the company I linked you to. I just bought an adapter for my wife's 2001 Grand Prix GT with the Bose system, in hopes of keeping the Bose system's integrity with the heads up unit, steering wheel controls, and OnStar system, while still using a better amplifier to feed better speakers. The PAC adapter is absolutely necessary to do that. I think you'll need a PAC adapter too.

GrandPrix104

How do you have your speakers wired on the amp ?
Each speaker to an individual channel or do you have multiple speakers hooked up to each channel.
Example: 2 speakers on one channel or bridged across 2 channels.

How are your speakers wired to the amp and what are the restances of the speakers 2 Ohm, 4 Ohm etc.

Get rid of that residental ground wire and use a piece of proper Auto power cable the same size as your main power feed for the amp. The wire only needs to be 4 feet or less and should only run you about $10.

Also you should never "Center Tap" a Battery with power wires.
The Amp needs to be able to dump power to ground as fast as possible.

Relocate your ground wire to the body or frame and sand the paint to shinny metal

My guess is that wiring is the issue with the amp or you might just have really bad luck.

Regards,
Dutch

ok I havnt had time to mess with this much lately but I'll answer some questions.

first I am using aftermaket speakers rated 50w @ 4Ohms for all four channels. Each speaker is wired to an individual channel. The sub is rated 200w @ 4Ohms. The speakers were each wired directly to the head unit with the factory wiring. Now I have spliced in between the speaker and the HU and run signal wires back to the trunk for the front speakers and done the same on the rear speakers as well. At any rate the amp goes into protect the moment you adjust the gain on Amp1 but you have a litttle leway on amp2/3. If the music hits a low bass note the unit may go into protect anyway. It does this on HLI or Low level inputs. I will test the speaker outs when i find my multimeter. I want to know more about line level converters though. That is how i had my RF amp hooked up as it didnt have speaker ins. Problem was it sounded like crap and had a bunch of other adjustments that I couldnt get right. I'm not a big fan of them. Thats why I bought an amp with speaker Inputs. PayPal still hasnt gotten back to me about getting my money back. I am thinking of getting a HiFonics Zues 5 channel amp for the same price that is new. Any thoughts on that brand?

of the 2, i would take a new amp over refurb. anymore both are mass produced amps..so you don't have the quality of the old school days...sigh...

ive never dealt with inputs you speak of. I could never see spending money and time into a stereo to retain a factory deck. deck can make a ho hum stereo into a omg stereo quickly....just opinion..everyone is different though.

I have to agree with the previous response. While this is sidetracking a little bit, -is there some reason why you're keeping the factory head unit? You could do a whole lot better than the factory unit, and you can get real line level outputs intended to drive an amplifier, instead of converting speaker outputs into amp inputs just to drive speakers again.

If it's possible, seriously consider an aftermarket head unit. You can also get much better functionality in an aftermarket these days, with support for mp3CD and good iPod connectivity.

exactly. depending on your tastes, if you are on budget, some shopping on ebay for used can get you into a nice unit as well. i have been extremely pleased with my kenwood excelon decks over the past 6 years. i have had probably 3-4 of them. i have 1 in my fun car and 1 in my daily. i will say though, stay away from D Mask decks..problems there..the newer ones are away from it though. that is reason for so many in years past..d mask messed up. i think i gave just under 100 for each my cd players i have now. both excelon models. Thing i like about them is that they have built in crossovers in them for highs and sub as well as sub output control. i pod connection, mp3 ability..so on. list is looooooong. plus, you can switch them to red as well....not all red display, but primarily red. to each their own though.... i have owned pioneer premier, sony mobile es and kenwood excelon.....i have always liked my kenwoods best. price per feature is good.

anyway, something to consider. for another 100 lets say...your stereo could sound WAY better.

Grandprix104

When you say you have "spliced in between the Factory HU and the Speaker" what do you mean ?

Did you cut the wires in half and connect to the speaker side and run that back to the Amp ?

OR

Did you just tap into the wire like a "T" connection ?


If you just tapped into the wire without cutting it in half then you are showing the Amp the resistance of both the speaker and the HU.
This would cause the Amp to go into protection.

Also how are you getting your musical signal back to the amp, which speaker wires did you tap into for signal and how many pairs ?

Regards,
Dutch

as for the wiring this is what i did on each side:

http://rawcomputech.com/bonnie/amp02.jpg

As for the HU. I do not have the $$$ currently to buy a new deck the $100 adapter and an amplifier. I am not sure I want a single DIN reciever either. I dont think they match well. I had been considering a JVC 2DIN but decided on an amp instead. I like how the factory HU looks and would rather keep it.

anyway, I'll be sending this thing back and getting something else. Another question though... If you could only amplify two speakers + a sub, which would you choose? Front 6.5s+Tweets or Rear 6x9s?

im trying to understand that pic. with the connectors overlapping and such.

from the head unit to the amp for high level you have drive pos/neg going back to amp from headunit... then from amp back up to the factory wire going to the speaker.....correct?

as for the deck thing. everyone is different on that subject. some like factory deck. but, its like buying a corvette , building up the motor for high HP, then putting a 1" air intake on it.....sorry, stupid terminology...but you get the idea. the headunit is THE center of the stereo.... regardless though. also you don't need any special adapter if you install a cd plyaer with rca outs. most out now have a front preout, rear preout and a set of sub preouts. most do anyway. install deck, run rca's back to amp for each channel and wahla. nothing special or fancy there.

Always amp your front stage before rear. The rear is really just for fill in a quality install. now if your out to just get loud...amp all of it. but mainly you want to power up your front stage and your sub. if you must amp rears, put smaller amp on them.

basicly I just cut the factory wiring and extended it back to the trunk to connect to the amp.

I will probably upgrade the head unit someday but that isnt going to happen any time soon. I'm not made of money.