Special Car Audio...

[PCGUY112887]

I hope this goes here... it's controled via PC so it should.

Anyways, i've been thinking of an audiosystem for a near future car. Most audio systems in cars have a head unit... and all speakers are powered from it. Then if you want a subs, you have an amp powering the subs.

Well I plan to have a carpuder and would rather have something set up on there to play music. Problem is... as far as I know it doesn't come out pre-amped! So I would have to run EVERY signal through some sort of amp... I planned on having 2 in the front (door sides), 2 in the back (by rear window) and a sub or 2 in the trunk. I'm not looking to make something crazy loud that will shake everything around me, just something with some power that sounds nice.

How would YOU go about setting this up? I can think of a few ways so far but i'm interested in how you guys would... $ is a factor here.

[Niku-Sama]

your talking about a computer in your car right?

[JKrepps]

most aftermarket head units have 4.1 sound (front 2 speakers, rear 2, and sub output), so any decent soundcard (or onboard sound) with 5.1 would be fine, you just would not be using the center channel (unless you want to go to that extra step, nice if you plan on movies or want better sq.

I "think" the output from your computer should be fine to run straight to the amp(s), but am sure someone on the boards will correct me if I am mistaken and you need any other hardware to correct the signal from comp to amp.

Good luck

<edit to add, Yes, you will need to have at least 1 aftermarket amp (more if you use multiple more application specific amplifiers, though the last time i looked there were some decent "all in one" amps that would be almost idea for what you are wanting to do), the sound output from your computer would have no chance of running speakers and would probably blow up if you tried)

Your local reputable car audio shop would also be a good place to start to get ideas of what you will need for a project such as this

[shard]

the amps use a RCA plug input, so if you had a minijack to RCA plug converter, then you will be in great shape, just pick up a 4 channel amp for the speakers, wich will have dual inputs for front and back, and get a beefy amp for the sub

[greenman100]

I'd do 3 of these

http://www.thezeb.com/p-USacoustics-USX-2050-2-Channel-Amplifier-105480.htm

bridge one of them for a sub, use the other two normally for doors

[PCGUY112887]

Humm greenman looks like a good idea, but $ is a huge factor for me.
These 4 channel amps... basically 1 would power front left, front right, rear left, and rear right?
http://www.jcwhitney.com/autoparts/Search?sku=sh514845B&storeId=10101&catalogId=10101&searchbtn.x=0&searchbtn.y=0

Seems like it would be most cost effective...
And for the whole minijack/RCA thing... say I had a 5.1 surround card in there... I could just use a mini to RCA for the front 2 speakers, then the same for the rear 2? I've never used a 5.1 card that didn't have Optical... so i'm assuming there is also a line just for the sub?

Then set it up in the comp as 4.1?

[JKrepps]

That would be the simplest, however you may want to plan on having at least a small sub for lows. Most small speakers (used in front and rear) really don't handle bass well at all, and while you may not like the car shaking "feel it a block away in your bones" bass, it really does make a difference to have some bass. However, if you plan ahead a little, you can always add it later. OR, there are amps that offer 4.1, 5.1 and even higher options (ie.. they come set up for all of the inputs and enough power to run a full system off of 1 amp)

Good luck, look forward to hearing how it turns out.

[greenman100]

Humm greenman looks like a good idea, but $ is a huge factor for me.
These 4 channel amps... basically 1 would power front left, front right, rear left, and rear right?
http://www.jcwhitney.com/autoparts/Search?sku=sh514845B&storeId=10101&catalogId=10101&searchbtn.x=0&searchbtn.y=0

Seems like it would be most cost effective...
And for the whole minijack/RCA thing... say I had a 5.1 surround card in there... I could just use a mini to RCA for the front 2 speakers, then the same for the rear 2? I've never used a 5.1 card that didn't have Optical... so i'm assuming there is also a line just for the sub?

Then set it up in the comp as 4.1?

Pyle is like a PC chips motherboard, or a powmax power supply. AKA a absolute POS.

and 2 of those US Acoustics amps are cheaper that 1 of those Pyles

use 3 mini to RCAs. one ofr the front 2 speakers, one for the back 2, one for the sub, and yes, sound cards have a jack just for teh subwofer

[Stoanhart]

I would do:

-Convert the FL+FR phono plug from the sound card to a set of RCA's
-Convert the RL+RR phono plug from the sound card to a set of RCA's
-Run those four RCA's to a nice 4 channel amp. I'm not sure the voltage on the output of a soundcard, but it's low enough not to damage an amp.

Take the Center/Sub phono plug on the soundcard, also convert it to RCA, but only the sub channel, not the center one. Or, convert both and run it to an amp with low pass filter, so you can strip out the center channel data. The amp should be a mono block or 2channel with bridge mode.

Use high quality RCAs. I used some crappy ones in my car, and it picks up and amplifies the RPMs of the engine. Seriously, the faster I go, the higher-pitch the sound gets. When I shift up, it drops lower again!

Get good ground points for the amps. Sand down some metal unit it's shiny and clean. Maybe redo the ground loop in your car. The "Magic 3". Check a car audio forum for that. Not necessary unless you get dimming lights from the sub, though.

[blueswitch]

here is what I do. I have an older Thinkpad that I run off of the cigarette lighter in my car. For the Audio I have an older Kenwood headunit but found out that Kenwood makes a cable that converts the CD changer input into an Aux in....so then I just run a mini plug from the audio out in the laptop to the RCA inputs on the converter cable and works like a charm. Nice thing about a laptop is that I have a 14' display in my car and it is easy to unhook it, take it inside and put it on my LAN to transfer songs on over or use it for another purpose. Check with your head unit's manufacturer if they make a cable like that...if if it may even have it's own aux in

[SB911]

I used to run a active crossover (3way) from my carputer to the rest of my stereo with 3 amps. I am more into SQ now so I run a deck. But using a active crossover it will preamp one set of RCA's and split it to the proper outputs. Then you can adjust cutoff frequencies and such to send the right sounds to the right speakers, balance and fade controls also. IMO it's the best way to go. Here is an example of an Active Crossover... http://www.crutchfield.com/S-QTDZR3hdoLS/cgi-bin/ProdView.asp?g=82600&I=20603KX2&search=active+crossover

[SB911]

Heres a good thread you might want to have a look at.......

http://www.mp3car.com/vbulletin/showthread.php?t=32430

[lowfat]

there is a guy on these boards (fyerdaug) that has a carputer in his car. and uses a home theatre amp to power the speakers. He is using a Audigy 2 ZS and using the optical output to the home theatre amp.

If this is going to be used for music only, the cheapest way to do it would be buying a deck with auxilary inputs, there a lot of decks under $200 i believe that have AUX inputs. Since car audio is just stereo (2 channels) all you would need to do , is make/buy a headphone jack to a RCA set.

and BTW Stoanhart that sound you most likely heard isn't caused my RCA's, more likely a bad ground. I have used $10 RCA's before, and i have used $50 RCA's before no difference really. As long as they are a sheilded RCA, your fine.

[FyreDaug]

Theres a couple things you should know first if you plan on using a soundcard
First, typically cheaper sounds cards put out 2.5V for the preout (meaning 2.5V will travel through the RCA cable) typical cheap headunits put out 3-4V and the higher end cards can put out as much as 4-4.5V (My audigy 2ZS) and high end HU can put out 5+V.

Maybe that doesnt mean a whole lot to you but from my experience the lower the voltage the more interference its susceptable to and the signal wont be as clear as a higher voltage. But aslong as you dont buy a $5 sound card you should be good if you arent planning on winning any sound quality contests, if you were I'd consider using optical or coaxail and sending that signal to a digital amp.

Another problem with using RCA's is that sound cards (even though they are 5.1 or 6.1) you only have a front L+R and rear L+R output, the 5.1 and 6.1 is trapped in the digital only option. So in order to hook up a sub you will need to split one of these signals (thus reducing its voltage in half) so youe rears could get maybe 1.75V and same with the sub. However if you get an amp with input and output RCA's you may be set, sometimes they will trick you though and not bring the voltage back up, so all it really does is split. Theres a couple amps that will keep your voltage up.

I chose optical and a home theater amp for a couple reasons, 1 being optical input (dont have to worry about interferance or voltages) and 2 because it has tons of settings in it to change, its own parametric EQ, bass/treb gains, distances, individual gains for each speaker AND it has its own 4.5V preouts on the back for a sub, with also has its own active crossover. And I only paid 300 bucks for it. Yamaha RXV 450

I'd direct you over to www.mp3car.com to get more information, its a good site but I found out about it after my system was done.

Good luck

[PCGUY112887]

I already have a SoundBlasterLive 5.1 that i'll put in there... and i'm a registered and posting member on mp3car...

I'm not looking for super high quality, just something that sounds nice but beats stock.

As far as the center thing goes... I thought that if you set it up for 4.1 analog, 1 minijack on the card would be for front left/right, one for rear left/rear right, and 1 for center? I'll have to find the specs for my card... they only have 1 new model of it now (slimline 7.1 live card).