DIY: Install New Amp & Sub

I was wondering the size we have to work with if we remove the spare tire. So I did some math and roughly came out to 3.27 cubic ft. if i did the math correctly.

Does this sound right to anyone who has removed the spare and installed a sub in it's place?
 
Has anyone done this ?

I dont know if i missed which color wires are connected from the factory connector to the RCAs but im really confused !

Halp me please :confused:

---------- Post added at 02:27 PM ---------- Previous post was at 08:25 AM ----------

bump
 
I just finished installing my amp and subwoofer over the weekend, and I had this thread open in my laptop the whole time. Great write-up, thanks for the pics!

However, I did have to make a few changes to my installation...

Basically, I had 2 problems:
1. The remote wire was only giving me about 6 volts (unlike the 12 volts that are mentioned in the original post). I guess this is enough to power the stock amp, but my amp just laid there dead when my radio turned on. There are 2 solutions that you could use, either build a relay circuit (which means running additional wires from the battery to the back of the car), or you can cheat like I did and tap into the power socket / cigarette lighter in the luggage compartment. This works because the 12V power socket only comes on with the key at ACC or ON, so it's an easy fix.

2. The audio signal wires (thin black and white wires) that used to feed the stock amp were unfortunately not "plug-and-play" for my amp. Using a voltmeter, I found that the signal is carried with a 6V DC offset. So when I made my RCA connection, the (-) wire was being grounded to the chassis ground, and it was causing my rear speakers to buzz and hum. After much head scratching and bumper kicking, I found that the difference in grounds between my amp and my signal was causing the problem. I thought I needed a Speaker to line-in converter (as mentioned in the original post), but in fact all I needed was a ground loop isolator. I got mine at radio shack (ie The Source) for about $20, but I'm sure you can find them cheaper online if you don't mind waiting for shipping.

It's also worth noting that I mounted my amp inside the spare tire (i cut a round board and screwed my amp into that). Unfortunately, I couldn't really think of anywhere else to put it, but with all said and done, I like the Idea of being able to take my subwoofer out to use my whole trunk without having an amp in the way.

Now, with everything in place, everything's up and running and sounding great.
 
I am only talking about the stock sub here - bridging a small Amp to replace the Amp currently inside the sub. No other speakers will be powered from the new Amp. I had planned on using your exact thread above to do this, because I already have an extra Amp, but it is relatively lower power. I thought bridging might be the way to get more bang since the sub is the only speaker I plan to power with this Amp.

Did you ever end up doing this prior to your new sub install? I have been thinking about this idea also and just by coincidence came upon a 200w mono JL amp the other day for $35. The amp is 200w mono and 2ohm stable, so I think I'll just connect it to the two stock 6s in series (they are 1ohm each). I might hook it up this weekend if I get time.
 
I dont understand how the amp connects to the car audio system... steps 10-14 are confusing any help?

All the wires you need are at the connector in the spare tire well. Just depends on your amp is how youll wire up the audio input from the stereo. Post up what amp youre going to use and itll be easy to tell from there if you need a line output/rca converter or if you can just wire them up directly to the amp(like I was able to do with my kenwood)
 
I dont understand how the amp connects to the car audio system... steps 10-14 are confusing any help?

This might help: It's the connector at the stock bose sub..

BOSEsubWIRES.jpg

---------- Post added at 01:16 AM ---------- Previous post was at 01:11 AM ----------

Would also be interested in the idea of connecting a stronger AMP to our stock subs. Anyone?

Here is mine: CLICK

EDIT: I forgot to mention that our stock subs are rated @ 1ohm each, so I wired them in series to a 2ohm stable amp. Works great.
 
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Thanks FXtion, awesome post.

I got me a pair of Subs and a Sony XPlod amp. Now the manual does not show me wiring for connecting two subs to the same amp.

What do i do?

I've two 10" Sony XPlod subs and a Sony XPlod XM1652Z amp.

Please advice..!!

RB
 
here is a link ot the user manual.

http://www.docs.sony.com/release/XM1652Z.pdf

The amp is 2-ohm stable. This means that you can hook up your speakers in "Series" for a combined load of 8-Ohm. when you increase the load on the speaker side, it cause the the amp to over load. This means that the native load of the amp (4-0hm) to drop down to 2-ohm, producing more power. This is becuase of the ratio between Wattage, impedance, and voltage. I forget the formula.

The way to hook up the speaker in searies is to hook up one positive post of one speaker to one negative post of the other speaker. then use the remaining positive and negative posts (one on each speaker) to the amp. The diagram in the PDF above will show that you'll need to connect one wire to the positive of one side and the negative to the other side of the amp (right and left).

Now, if you speakers have dual voice coils, you'll need hook up all posts of the speaker in series (+ of one voice voil to the - of the other) and then hook each speaker (+/_) to the right and left side of the amp. On the input side, you can use the hight level impout of the amp to connect the Sub wire

Good luck. You can do a google search on "serial speaker wiring" and "dual voice Coil speaker wiring" to show you how the speaker wiring are supposed to go. Note: some documents on the web talk about 8-ohm speakers. That's for home use. Car speakers are usually 4-ohm. You need to end up with 8-ohm on speaker side to have 2-ohm on amp side. You almost never want to end up with 8-ohm on the amp side. It might damage the amp. Also, you must never exceed the max impedance level of the amp which in this case is 2-ohm (NO 1-ohm).

Thanks FXtion, awesome post.

I got me a pair of Subs and a Sony XPlod amp. Now the manual does not show me wiring for connecting two subs to the same amp.

What do i do?

I've two 10" Sony XPlod subs and a Sony XPlod XM1652Z amp.

Please advice..!!

RB
 
FXtion, thanks a lot for this write up..!! I successfully installed my AMP and Subwoofer.

:smile (2):

Points to Note:
1. I broke the plastic tip at the battery end as I tightened the bolt too hard.
2. I did not have an extra tip so I bought a couple of slugs to connect to connect Ground and Positive wires to bolts.
3. I bought a kit off Amazon which had everything to install the AMP
4. I had a tough time to make a small cut on the rubber at the battery end and push the wire down into the vehicle. Be VERY careful not to cut the other wires there. It could turn to a disaster.
(Amazon.com: Boss Audio KIT-2 Complete 8 Gauge Amplifier Installation Kit: [email]Electronics@@AMEPARAM@@http://ecx.images-amazon.com[/email]/images/I/31psMrmVC9L.@@AMEPARAM@@31psMrmVC9L)
4. I used a high to low converter from Best Buy and went thru RCA to AMP.
5. I do not know where to put my AMP and the woofers are too big for the car. The THUMP is huggeee...!! So a word of caution, when buying an AMP+Woofer combo, BIG ain't GOOD all the time, for people who don't need this huge a thump..!!

The whole setup took me only 3 hours, for a noob like me :nerd (2):, im at upstate NY so I had to bite the cold and get it done. I guess anyone could do this especially with an excellent writeup from FXtion.

Thanks to all.!!

Regards
RB :ninja:

AmpSetupOnFX35


AmpSetupOnFX35


AmpSetupOnFX35


AmpSetupOnFX35


---------- Post added at 03:33 PM ---------- Previous post was at 03:30 PM ----------

The pic din get inserted here..
Try this Link below:::

http://picasaweb.google.com/raghubhaskar/AmpSetupOnFX35#
 
Is is possible to add another factory bose sub amp and run one amp to each factory sub... or whould that screw up things... is sounds like the ohms would be screwed up if you only ran one speaker off of each amp... does anyone know of a decent inexpensive amp that could be used to simply replace the factory amp?

---------- Post added at 02:39 PM ---------- Previous post was at 02:30 PM ----------

I just had another idea/question. Would it help things noticably to simply run a seperte low gauge quality power source to the stock sub amp to replace the factory power supply which appears to be inadequate? Also, using better quality speaker wires from the amp to the subs... should help too right?

Just wondering... I am almost happy with the stock setup... and don't want a sub cabinet in my trunk....
 
...
Also, you must never exceed the max impedance level of the amp which in this case is 2-ohm (NO 1-ohm).

Just to clarify, the impedance rating of a solid state amplifier is it's MINIMUM rating. The combined resistance of any speakers connected should always equal or exceed this rating. The safest bet is just to match the rating exactly.
:tup:
 
Rpm goes up and down

My fx45 has been doing this for I don't know how long it's just that I noticed it when I turn the headlights or the music is too loud and everybody says is normal but I have tried other cars and I don't see this problem . Sometimes I think is the battery going bad but not sure, please if anybody knows !
 
I want to thank you for the DIY. It was a breeze for me and it saved me some money. I'm running a Polk audio enclosure db1212 with an alpine mrx-m50. I have to tune it a little bit but it sounds great...
 
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