laxxman111

I recently installed a M500 apline amp with a 12 inch 4 ohm alpine subwoofer. I am using the FACTORY head unit, it is the bose system. I used a line out converter and 6 guage wiring system. This setup has worked in my friends cars plenty of times before. For some reason at low volumes the subwoofer works, i can turn the amp up to make the sub louder at low volumes and it works fine, but as soon as the volume goes past 15 the sub cuts off and the amp stays on. Im assuming that it isnt the amp because it stays on. If i turn the volume down again to 14 the sub will turn back on after a couple seconds. I didnt want to install an aftermarket head unit, I like the stock one. I have tried everything i can think of changing ground wire location, changing line out converter, and trying wiring the sub at 2 ohm and 8 ohm. So if anyone has any idea please help me! Im so confused

WikkedOne

where did you tap the signal wires for the LOC? (before or after the bose amp)

you say that the amp stays on, does that mean that the power stays on but it's going in a protection mode or something?

laxxman111

okay this might sound crazy but i am kinda confused about the bose system, i bought the car from another person a little while ago, it had the bost tweeters but i didnt see the bose amp, it is supposed to be in the trunk between the rear speakers correct? but where i spliced the LOC into was into the rightrear speaker if that answers your question. Also i mean the amp stays on as in the blue power light stays on the whole time, it doesnt dim or shut off, the sub just stops no matter what the gains are set at on the amp if the volume is turned up above 15. I have wired a few cars and everything went fine, this just is completely confusing me. If anything else im trying to explain is unclear let me know.

wahkupup

iTrader: (3)

If you have the Bose system and tapped in after the main amp, the "auto pilot" will mess with your sub.

Tap in before the bose amp.

laxxman111

where would you recommend that i tap into then? if you have any pictures that would help greatly

wahkupup

iTrader: (3)

https://www.rx8club.com/showthread.p...129#post252129

see pic in #34.

wahkupup

iTrader: (3)

This is all sticky'd. Very first post in the interior,audio sub forum.

laxxman111

thanks i did read this before, but 1 problem you might be able to help me with, i dont see where my bose amp is.. i just dont see a rear amp at all... so im not sure about that wiring. i wired from the battery and ran in through the main wiring harness. everything was wired correctly, well as me and my friend believed to be correct. I just dont know what would explain the sub not working at all when the volume is turned past 15, even with the gains turned all the way down, maybe you or someone else has had this problem and could help.

firebirdude

iTrader: (3)

First, we need to establish if you have the Bose system or not. If you don't see the little 6" x 8" silver colored Bose amp right next to the right rear speaker (from the trunk), then you don't have the Bose system. Plain and simple. I've heard rumors of 8's saying Bose elsewhere in the car, but not coming equipped with the Bose system. I personally think it's something someone added after it left the factory. Maybe the previous owner just thought the Bose tweeters look cool. Who knows. But to top it off, the factory headunit for a Bose system is different than the factory non-Bose headunit. So it couldn't be as simple as removing the Bose amp or adding in the Bose speakers later. I'm betting you never had, and still don't have, the Bose system.

Next, which Alpine sub do you have? Model number? You said it was 4 ohm, then said you tried to rewire it into a 2 ohm and again to an 8 ohm load. You can't do all those combinations with any sub Alpine makes. Probably just a misunderstanding, but I just want to make sure everything is clear so I can help you.

It sounds like your amp is kicking into some sort of protection. Just because the light on the amp doesn't turn off or change color, doesn't necessarily mean it's not kicking into a protection mode. It doesn't have to be a temperature protection. Many higher quality amps have low impedance protection (keep in mind that impedance fluctuates with frequency), over current protection, low voltage protection, high voltage protection....and probably a couple I'm not even aware of. Maybe high/low voltage on the RCA inputs or some sort of clipped output protection (that would be sick).

If you turn the gain way down on the amp, can you turn the volume on your headunit higher before it cuts out? Also, remove the speaker wires from the amp and test the electrical resistance of the subwoofer using a multimeter. Post up what you get.

laxxman111

okay that is what was confusing me... because of the bose tweeters. Thats clears one part of this up now, not having the bose system. Next, if the volume is at 14 i can turn the amp as low as it goes to turn the sub down, or as high as the amp goes to make the sub louder (obviously), however as soon as the volumes goes to 15, no matter if the gains are turned all the way up or all the way down the sub completely stops working. The sub is an apline type r 12 inch, heres the link http://alpine-usa.com/product/view/swr-1243d/ the sub can handle 600 watts rms and 1800 watts peak, i know the amp is not to much for the sub... my friend ran a 15 with my same set up and he ever used smaller gague wire, so mine should be working.

firebirdude

iTrader: (3)

First, you're using a 4 ohm dual voice coil subwoofer. Your wiring options are either 2 or 8. Using only one coil would be the only way you could present the amp with a 4 ohm load, and that's something you don't want to do. But like I said in my last post, use a multimeter to test the electrical resistance of the sub. Check each coil individually if you can. Maybe one is now damaged/blown. There's not a doubt in my mind the Type-R can take anything the M500 can throw at it.

What line output converter do you have? Is your line output converter adjustable? Most are. Look for a small **** that usually takes a screwdriver to adjust. What is it set at? All the way down? All the way up? Does adjusting it allow you to turn your volume up further or even less?

This is tough to troubleshoot without actually being there and being able to check things for myself. I'd also watch input voltages on the amp while music is playing. If they ever dip below 11-12V, then you may have a bad ground or a weak connection somewhere. Also, maybe try unplugging the RCAs on the amp and using an RCA/3.5mm adapter to plug an iPod up. Crank it and see if the amp ever cuts out.

laxxman111

also if i test the sub what resistance am i supposed to be getting? i havent tested a sub before sorry

firebirdude

iTrader: (3)

Depends how you have it wired. If you just connected both positives together and then both negatives together, that is a parallel connection and you should be seeing ~2 ohms nominal (likely right around 1.85 according to your owners manual). If you have a series connection, then you should see ~ 8 ohms nominal (likely right around 7.4 according to your owners manual).

Also keep in mind the subwoofer cannot be connected to the amp when you're testing this. Pull the speaker wire from the speaker terminal on the box and stick your test leads in there or at least disconnect it from the amp and touch your test leads to the wires themselves. Again, if it's not too much work, pull the subwoofer out of the box and disconnect all the wiring from it. Then stick your test leads right on the connections for each coil. Each coil should meter up right at 3.7 ohms. If one measures infinity, zero or several megohms...then it's toast.

laxxman111

i tried testing it but i kept coming up with like 300 ohms or something, but the sub is brand new just out of the box, i may have read it wrong because it wasnt a digital one and it was kinda old and confusing lol but i just got the sub.

laxxman111

I GOT IT!!! maybe i should have tried actually starting the car before assuming it doesnt work. I only put the key on accessory and it wouldnt work, i believe the battery is getting old and thats whby it didnt have the juice to keep the sub going until it was running.

firebirdude

iTrader: (3)

laxxman111

haha yeah thanks for the help though. never had this problem before on any other car. by chance i was going for a drive and left the sub wired up and was only gonna listen to it at like 14 and then turned it up and it just kept playing. talk about dumb luck

firebirdude

iTrader: (3)

I'd call it dumb something...

laxxman111

btw i was looking at your pictures of your car, well before you sold it but it looked real nice, i was wondering if the subs you had were 12s? because i am in the process of building the fiberglass enclosure for the corner of the trunk, and im making sure the 12 will fit. did the box you made fit easily in the trunk?

firebirdude

iTrader: (3)

They are 10" subwoofers and I didn't make them. But several members on this board have built their own wheel well enclosures, exactly like mine, with 12" subs.

laxxman111

okay thank you, just figured id ask while you were helping me with the other stuff, mines about done. i would post some but theres already alot of other threads. not trying to steal the credit from everyone i got the idea from lol