S2000-specific Audio/Electronics FAQ v.2.37
Registered User
Joined: Jul 2008
Posts: 63
Likes: 0
-Optional: Rears
These are for rear fill only, and generally can be run off the head unit amp. Many EJ's don't even run rears. This can be a good solution if you are not concerned about the finer points of sound quality and all you want to do is hear music with the top down. Our recommendation for just hearing music better is to replace the head unit and add rears.
These are for rear fill only, and generally can be run off the head unit amp. Many EJ's don't even run rears. This can be a good solution if you are not concerned about the finer points of sound quality and all you want to do is hear music with the top down. Our recommendation for just hearing music better is to replace the head unit and add rears.
can someone explain what are the "finer points of sound quality" that would lost if i were to do this mod?
Registered User
Joined: Jul 2006
Posts: 459
Likes: 0
From: SoCaL
The link for subwoofer box measurements of the 3 different boxes don't work anymore.
http://www.geocities.com/mariobonifa...asurements.htm
Anyone have this? I need the box with 0.8 cf.
http://www.geocities.com/mariobonifa...asurements.htm
Anyone have this? I need the box with 0.8 cf.
Registered User
Joined: Jul 2007
Posts: 3,187
Likes: 3
May be worth adding the rated capacity of the stock alternator - 105A - and what that means:
A * V = W
105A * 12V = 1260W (continuous)
105A * 14.4V = 1512W (continuous)
And I get a ~0.4V drop when I turn the HIDs on with the car off. With the same math, guessing ~600A for the battery makes that around a 240W draw.
So with the lights on, systems pushing over ~1kW continuously will need an alternator--for bass-heads, that could be an issue.
A * V = W
105A * 12V = 1260W (continuous)
105A * 14.4V = 1512W (continuous)
And I get a ~0.4V drop when I turn the HIDs on with the car off. With the same math, guessing ~600A for the battery makes that around a 240W draw.
So with the lights on, systems pushing over ~1kW continuously will need an alternator--for bass-heads, that could be an issue.
Joined: Feb 2009
Posts: 278
Likes: 0
From: Montebello
^that does not seem correct if key is not on ACC or Ignition position. It is a lead acid battery we are working with so the voltage under load is different than when it is almost open.
I have not measured nor calculated it yet but the lighting system should draw around 150W at most
What we should consider the most is that the car "could" be drawing around at least 50~60A when it is running with every stock load: ignition, fuel injection, ECU, lighting, a/c, blower, and the EPS.
Killing the battery is just a small thing, what happens to the alternator and the rest of the on board electronics is what we really need to think and worry about.
I have not measured nor calculated it yet but the lighting system should draw around 150W at most
What we should consider the most is that the car "could" be drawing around at least 50~60A when it is running with every stock load: ignition, fuel injection, ECU, lighting, a/c, blower, and the EPS.
Killing the battery is just a small thing, what happens to the alternator and the rest of the on board electronics is what we really need to think and worry about.
Registered User
Joined: Jul 2007
Posts: 3,187
Likes: 3
Yeah, it's not surprising to hear that's likely inaccurate--I should have stated that it wasn't a multimeter load or anything very accurate: my DEH-P800PRS HU has a voltage readout, and that's all it was based on. The battery was quite cold at the time, so 600A is probably a high estimate also. I though it was a starting rough estimate, but as someone trained in the field, I'd trust your estimate much more than my SWAG-experiment 
That last part makes me wonder--the point of what happens to the alternator and on board electronics.
Years ago I had a system with 300WRMS to speakers and an Xtant X1001 wired to a pair of DVC subs wired in parallel. I had this in my brother's then-new 02 dodge neon for a few months. When the amps had pretty well run the battery dry, I could feel the car actually hesitate or stumble whenever/while the bass hit hard. I wondered if the spark plugs weren't getting enough juice or what was happening. Interesting...
That last part makes me wonder--the point of what happens to the alternator and on board electronics.
Years ago I had a system with 300WRMS to speakers and an Xtant X1001 wired to a pair of DVC subs wired in parallel. I had this in my brother's then-new 02 dodge neon for a few months. When the amps had pretty well run the battery dry, I could feel the car actually hesitate or stumble whenever/while the bass hit hard. I wondered if the spark plugs weren't getting enough juice or what was happening. Interesting...
Joined: Feb 2009
Posts: 278
Likes: 0
From: Montebello
lots of problems actually current starvation leading to low voltage and then the infinite loop of voltage vs current for the silicons... Lower voltage means the chips will have to draw even more current, and there isn't enough current to start with, sounds weired but this puts a lot of strain on the entire electrical system.
Alternators aren't designed to be running at 100% at an extended period either. And, the more it generates, the hotter it gets, and the lower it outputs... Definitely not fun. I'm not a pro at alternator designs though, so I'd rather leave it to someone who is really into it.
The problem you experienced is also related to the sensor feed back signals. They were designed to send their readings in certain voltages, but if the voltage supply is not within design specification, the signal they output are really off than what they were supposed to be. In additional to the already chocked electrical circuits on the vehicle, ignition systems and fuel injection systems, the car would just run really really poor.
current starvation leading to low voltage and then the infinite loop of voltage vs current for the silicons... Lower voltage means the chips will have to draw even more current, and there isn't enough current to start with, sounds weired but this puts a lot of strain on the entire electrical system. Alternators aren't designed to be running at 100% at an extended period either. And, the more it generates, the hotter it gets, and the lower it outputs... Definitely not fun. I'm not a pro at alternator designs though, so I'd rather leave it to someone who is really into it.
The problem you experienced is also related to the sensor feed back signals. They were designed to send their readings in certain voltages, but if the voltage supply is not within design specification, the signal they output are really off than what they were supposed to be. In additional to the already chocked electrical circuits on the vehicle, ignition systems and fuel injection systems, the car would just run really really poor.
Registered User
Joined: Jul 2007
Posts: 3,187
Likes: 3
Hadn't thought about it quite to that level--the current <--> voltage fight and design voltage input range issues. Hearing a bit about the mechanisms makes it easier for me to understand the problems, although I doubt I'd foresee them in advance. Interesting stuff!
Joined: Dec 2008
Posts: 2,634
Likes: 0
From: Valrico / Tampa, FL
I've read through the whole FAQ and am a seasoned installer of car stereos (as the screen name might hint). The question I have that would probably fit this FAQ well is 'what are the differences between MY head units?'. I know the speakers changed throughout the generation's revisions, but did the head units (hopefully I didn't simply miss this being addressed)? I'm looking to help a member upgrade his setup and want to know everything possible before I give him total advice.
Thanks!
Thanks!