Wiring advice for an old DIYer

First off, very nice community here with excellent discussions and advice.

I'm an old DIY enthusiast who's coming out of "retirement" to upgrade a 2005 tacoma on the cheap by using old equipment as well as buying some new stuff and trying out new things.  My overall goal is to build a quality system on a budget.

My main questions have to do with wiring and cap or no cap and running 1ohm vs. 2ohm, but let me start from the top.

old equipment I plan on using:

Upgrade plans and questions:

- first upgrade The Big 3 (btw, thanks to the OP of that article.  I definitely would've forgotten about upgrading those wires if not for that article!)

- install ~60ft2 of sound deadener.  I will most likely buy the cheaper padding but was curious about whether I should also invest in a gallon of the liquid stuff.  I'm not going to be anal about removing unwanted sounds.  My goal is to test the waters with using a modest amount and listen for any improvements.  Note my previous car had no sound deadening, so this is new territory for me.

- To keep costs down and use existing factory spaces, I'll buy some 6.5" coaxials and a pair of tweeters, and also reuse the infinity 6x9s.  These will be connected to one of the 700s amps which I plan to run ~2ohm stereo, ~250watt per channel according to the manual.  This is a similar setup to what I ran in the previous car where the amp's input sensitivity was at its lowest setting with the help of the BLT and ran cool to warm, not hot, for two years before I shelved it.

- buy a pair of  these: http://www.soundsplinter.com/rli_ignition_series_8_inch_and_10_inch_diy_subwoofer_drive

I'm undecided on 8" or 10".  Can anyone provide some feedback on these subs?  I don't know much about this company, but they caught my eye due to their power handling, excursion and low sealed volume requirement.  Also, should I buy the single or DVC 4ohm?  I was thinking DVC for resale value.  I will use the other 700s bridged mono, which according to the manual is stable at 1ohm mono, but one of the pro installers here mentioned he would not run 1ohm.  I understand the amp will run hotter, but shouldn't the amp be able to handle it if it's rated for 1ohm?  What are the other disadvantages, and should I stick with a 2ohm mono load?

- Cap or no cap?

- 4awg or thicker?

- fuse at battery

If anyone can help me out with these basic questions, I'll be ready to start this project.  Thanks in advance,

SonicFlux

Edit: correct html link is http://www.soundsplinter.com/rli_ignition_series_8_inch_and_10_inch_diy_subwoofer_drivers.html

Ref 700s in 1 ohm mono = real bad bad bad bad bad bad idea. Here is where I would start. Ship all old Soundstream amps to Rob. If this is not an option, follow plan B below.

(1) Ignore the liquid sound deadener and concentrate on a good deadener like Brown Bread.

(2) If you have the cap, use it as sometime yes they do indeed help.

(3) Definitely do the BIG3 (or4) and use 0 gauge in the engine bay. The Ref700s is a power hog, with two of these hogs I would be using 0 gauge for the main power run and definitely read the what is a proper ground sticky.

(4) Run the rear speakers off of the cd player for the time being otherwise you will not be able to set the front stage / rear fill that is necessary for proper sound reproduction. Use one amp to operate the front speakers, if you must, find another small amp to power up the rear speakers.

(5) Use the second amp to drive a single 10" sub. Choose a single 4 ohm version that can handle what that amp can produce, which should be up around the 700 w rms into 4 ohm mono.

(6) Use the cap as the distribution point to run the 0 guage feed line from up front. It can then split to the 4 gauge lines to feed each amp.

(7) Use a circuit breaker of at least 150 amps or a wafer fuse of at least this rating up front. It is important here that you are fusing the wire, not the amplifiers. The sole purpose of this fuse is to protect the vehicle in event that this wire is damaged.

(8) Did I mention to send me these amps?

Thanks guys,

That gives me enough to get started on the project.  Since I'm upgrading on a budget I'll have to shelve some of the ideas mentioned above like running 4channel for soundstage, but I can always come back to finish the job later.  In any event, this interim solution should blow the pants off the tacoma's "premium" jbl factory system

One last question.  I calculated the theoretical max power of this system to be either 1000watts or 1200watts depending on whether I run the sub(s) at 4ohm or 2ohm, respectively.  However, 98% of the time the system volume will most likely be cranked down to a modest level to suite my tastes, not to mention the amp input sensitivity levels will be set very low.  So is it safe to assume that this system's real world normal "daily listening" power output will be no where near 1000watts?  Yes, no?

What I'm getting at is the thought that perhaps 4gauge main power wire could be sufficient for low volume regular listening.  Right now I'm very tempted to reuse 4gauge wire primarily to save money and knowing that I will never be pushing the amps to their max performance levels.  After all, if 98% of the time the system's real world power output is actually closer to 500watts than 1000watts, then according to the charts 4gauge would be sufficient.

Install the four gauge, and at some point after everything is working, crank the system to louder-than-you-like-it volume.  The amplifiers will still get the juice they're craving even if the power and ground wires are a bit small for the task.  That is, of course, assuming there is an inline fuse that will allow this amperage flow, and that the alternator is up to the demand put upon it.  The point being this:  the wire may be a bit small for the headbangin stuff which you will rarely get to, but it won't limit the current flow by much (just some loss in heat).  The wire will get warm, that's all.  Wire size is more about safety than current flow.  When it gets hot there's a problem. 

Wire it the way you are going to use it.  My personal car has a 40 amp main wire fuse and I've never pulled more amperage than that fuse will allow.  I couldn't be in the car with a system that loud.

It would be safe to assume that the real world daily listening wattage would be at around 100 to 200.  1 watt to your sub, you're at about 87 db.  64 watts, 105 db.  Add to that the relative gain produced by the cabin, at least 6 db.  Most home speaker systems can't achieve that db level cleanly.  That is way loud.  Components will take less.  It is a strange curve, this power-to-decibel relationship.  It only gets steep at the very end.  And by that time your ears will have gone into protection  .

Whenever someone uses phrasing such as this, where they liken gain settings to relative position, it raises a red flag.  Make sure you go through the steps to set the gains of the amps to the output of the deck.  Search 'gain' in forum topics for a bunch of threads that give tutorials.  A proper gain setting could be anywhere along the travel path of the dial (screw).  In fact, you shouldn't even be looking at it when you set it...you should be listening.  Good luck with your project.  You sound like you're a lot like me.

Again, much appreciated.   I understand what you're saying about input levels and will be sure to check the tutorials.

When I first installed the 700s in my old car I remember settling on leaving the input gain ~40% max.  I later purchased a balanced line transmitter to try and eliminate some very faint yet extremely annoying engine noise.  Not only did it eliminate the noise but I remember decreasing the amp's input level down to ~5% max to compensate, and the amp seemed to run slightly cooler after that.  Of course, the BLT had its own input level... so many variables in installing a system...  it's fun getting back into it.

The more I read, the more I realize I need to read more before starting this project!

SonicFlux