Winter project

[Slow91z]

Hey fellas I was looking through here earlier and decided to ask you guys some questions I have on car audio since I noticed that there seem to be some guys in here quite good at it.

Winter project is as follows unless you guys make me change my mind.

Alpine MP3 Deck - There are 2 I am looking at the major difference being one has 2v preamps and the other has 4v...I had a Pioneer in my last car that had 2v and I didn't like that nearly as much as just using the speaker outputs...it was WAY to quiet...Would 4v outputs fix that?

I have 1 Infinity 12" reference in a 1 cubic foot non ported box (maybe it's 1.5 can't remember for sure), sounded great in my Eclipse but I'm worried that it won't be enough to get through the backseat...Also do you think I should point it forward (which how it was in the Eclipse, and sounded awesome), or some other direction?

Amp will be a Infinity 111wx4, with 2 Channels going to the rear speakers (6x9 Infinity's I think), and 2 bridged to the sub.

The fronts are Pioneer and will be running off of the deck alone.

Thanks in advance for any and all help...Sorry it's so long I just hate multiple threads for the same car...I try to get it all out at once.

 

[SilverSleeper]

As far as 2v vs. 4v output voltage:
well, with the amp at the same input level settings, yes, the 4v will be louder. But, the main reason to step from 2v to 4v is to reduce the amount of amp gain needed to achieve a loudness level.
Increasing output voltage while decreasing amp input gain will get a stronger signal through your amp and a cleaner sound.
If you dont understand what Im saying, just go turn on your home stereo amp without any signal (ie, no CD or radio playing). Notice that the more you turn it up, the more static you hear. This is the equivalent of turning up your car's amp gain. You turn up the input voltage so that you turn your amps gain down and reduce that extra noise.
You need to match your pre-out voltage to your amps input level. If you overdrive your amps with too much input voltage, it will distort your sound. If you are using your speaker outs without a converter to drive your amps, thats a big no no.

As far as your amp and speaker setup:
Why would you deck power your front speakers, and then amp the rears and subs? You will get a lot of your mid-high frequency information from your rear speakers, and the fronts will not even be heard. I guess if youre used to that, then thats your choice. That could be a reason you say it sounds too quiet. Its gonna sound weird. Generally speaking, your fronts provide your mid-high information, and if you have rear speakers aside from subs, they are there for fill only, and are not as driven as the fronts.
Now, if you are using your 6x9s for mid bass, thats different. You would want to cross over those to keep your mid-high info out of them and up front to your Pioneers.

You have a good start though. good luck!

 

[Slow91z]

The reason I'm not amplifing the front is because they are rated for about as much power as the deck puts out...Seems to make more sense then over powering them with a amp, I mean they are tiny, please correct me if I'm way off.

What converter are you talking about for the amp input?? If the amp has speaker inputs what's wrong with using them?? I mean ain't that why they are there?? It sounded clear as a bell in the Eclipse...Once again if I'm way off please correct me.

Sounds like the 4v preamp is perfect for what I had going on...I had the amp gain at max and could barely hear it with 2v, and with the high inputs hooked up I had the gain around the 1/2 mark and it was twice as loud.

 

[SilverSleeper]

Ok, youre talking about an amp with speaker level inputs. Gotcha.
I had visions of (yes I have actually seen people try to do this) wiring the deck output into the RCAs that lead to the amp inputs.
The speaker level inputs will probably be louder than a 2v RCA, but also less clean at the same time. 4v should work well for what you need.

Are you using 3.5" Pioneers for the dash? Yeah, you wouldnt want to amp those little guys anyway.
What you have will still sound ok, just that your front stage is gonna be lacking with only those 3.5"s up front. If you are serious about an install with this car, youre gonna have to step up to something a bit bigger for front stage. Some people have done kick panels, or door panels with a 5.25 or a 6.5 speaker. You will not believe the difference it will make. I started with a very nice pair of Boston Acoustics 3.5's up front. Then I saved the money for the Q forms kick pods, and put the Bostons in there. Just the better imaging alone was worth it. Then I put in Infinity Kappa 5.25 seperates, and it was like night and day.

Also, the smaller speakers will handle more power than they are rated for, you just dont want to send really low information to them. I actually amped my Boston 3.5's for awhile, and they did pretty well. This was with a 100x2 rms amp, also. But, they were crossed over pretty high when I did amp them.

Im just trying to help. Ive gone down that road before, and while bass is nice, you will miss a lot of sound by keeping the small drivers up front. Your rear 6x9s will give you the higher freq's, but you get the sound indirectly, as in, the sound bounces off the glass, gets absorbed by the front seats, etc. Its gonna sound weird.

 

[Slow91z]

I see where you are coming from...Right now my main consern is music that i can turn up louder then the wind noise on the interstate, and I want it to be fairly clear.

If you saw my car you would know it's a severly low budget car...Primer, benchseat no option car that I paid $4000 for.

It runs 11's now so it's time to start on the stereo for the winter...I figure this will be pretty nice, my tape even broke last spring so I've been screwed all summer...I want to do this and then paint and after everthing is done I'll worry about making it sound perfect.

Yeah just 3.5's up front, I got them cheap, and they sound really good, just not loud.

I'm pretty set on the upper class deck, the 4v outputs might be just right for me.

 

[Slow91z]

Oh yeah what do you think about the sub placement??

 

[SilverSleeper]

Well, sub placement is a matter of opinion.
Some people like to face it rear, others face it front.
You get a different sound either way, so you probably want to test it out if thats possible with your box design.

When I built my box, its pretty much the same dimensions around, so I tried it out facing either way. I liked it facing forward, but then, thats just me. I have 2 JL 12w0's, BTW. It just sounded tighter that way, but also it decreases the rattles coming from the trunk and other parts in the back.

One thing you could try to do, is to low-pass crossover your 6x9's, which would cut down on the high freq, and high-pass x-over your 3.5's. If you x-over your 3.5's, you will be able to turn it up more without them distorting. Thats the main reason they wont handle much power. The bass freq will destroy them faster by mechanical overdriving, than by not handling the actual wattage.

 

[1QuickV6]

I'm in agreement with Jason here on everything. With a 4-volt head unit, you should definitely run two pair of RCAs to the Infinity amplifier. And as he had suggested, I'd like to see you power the fronts with good power. Nowadays, better head units do have built-in crossovers for their internal amplification, so that may end up working out on a budget (I'd cross the little 3.5s over at about 100Hz, if possible with your head unit). It sounds like you have good equipment to start with, so your results should be satisfactory right off the bat.

If you are not into building up your front stage with kick panel pods or modifications, a nice, high quality set of 3.5s up front (i.e. Infinity Kappa, Focal, MBQuart, Boston Pro) may help a little bit. But your ears will tell you what's good, and you may love your Pioneers in the Buick. You may or may not like the idea of rear fill with your 6x9s, but it's again a matter of taste.

Use good power wire (I'd recommend a 4-gauge run to the amp, if it's back in the trunk... just in case you get the bug and decide later to go with a dedicated sub amp), good interconnect between the head unit and amp (there are some good deals on ebay or see your local guy for some recommendations), and take your time with the install. It's a winter project, so do the tough stuff once and do it right.

Good luck, and check back and let us know how it's going!
Erik

 

[Slow91z]

In my Eclipse I had the sub faced forward because it sounded cleaner...While listening to rock it sounded like the drummer was in my backseat...That's what I like, massive amounts of bass don't mean much to me it's punchy bass I like.

I planned on using those passive bass blockers in the front, and the amp has variable high/low pass filters to use for the 6x9's and sub.

I think I'm just gonna push the pioneer's till they die (they were cheap why not) and after that I'll think about upgraging them.

Thanks for the help fellas I'll try to keep yall updated.

 

[SilverSleeper]

If you are interested...
I have my Boston Pro 3.5"s still around.
They are a great little speaker, and really clean.
They can handle quite a bit if you do want to amp them.
Just thought I would pass that on.

Yes, keep us updated. Hope we can help you get the sound you want out of your system!

 

[Slow91z]

I'll keep that in mind after I get the rest done...I may want to pick them up.

 

[Slow91z]

Hey guys I'm back again...My deck is on the way, should be here tomorrow...I ended up getting the Alpine CDA-9830.

I'm having 2nd thoughts about my amp though, I might just buy a mono or 2 ch. amp and since I can't afford 6x9's right now anyway.

My questions are
1. WHY ARE MONO AMP'S SO EXPENSIVE?

2. I was talking to a buddy and he said if you bridge a 2 ch. amp you'll still have 4 ohm's going to both ch's and therefore you're gonna have to spend just as much as you would on a mono amp...I thought if you bridged a 2 ch. amp it basically split the ohm's to 2 ohm's per ch=higher output.

Example=Mono Rock Fos Amp $500 300w RMS@4ohm.

2 ch. Rock Fos Amp $500 150w x 2 and in his way of thinking 300w bridged to a 4 ohm speaker.

2 ch. Rock Fos Amp $250 75w x 2 and in my way of thinking 300w bridged to a 4 ohm speaker.

CONFUSED please help.

Oh and I used Rock Fos just as a example I am in no way set on a amp company...I am actually looking pretty hard at Profile amps...They seem VERY nice for the money.