I've decided to replace my stock stereo system with an upgrade . I still have the original 70 amp alternator in the car, and just had it totally rebuilt . I'm upgrading to the Pioneer 7900 series radio, and I'm running 2-6x9 Infinity 3 way (300w max)and 2-4x6 Infinity 2 way speakers (120w max)in the rear, and 2-4x6 Infinity two way speakers (135w max) in the dash. I'm thinking of installing an amp and was wondering if the alternator will handle it without any additional upgrades?

 

Yes with ***'s. The radio will not pull all that much more amperage. The max wattage is not something you should ever evaluate a speaker and amp combo with. You will never reach max wattage unless you have a heavy metal rap duet playing at maxed out all the way hard over volume.

You probably have about 150 - 185 watts or RMS draw. I would put that right around a 20 amp draw from the charging system. Now, with headlights and HVAC stuff running you will be pushing that alt to the limit but it should work just fine.

That being said, it's always a good idea to install a better alt. Reason being, that 70 amp probably puts out somewhere south of half that at idle. That means at a stop light you will have dimmed headlights and will be running off of the battery. Not good for battery life.

I suggest a CS130. They are cheap and very easy to install so long as you get a 12 & 6 clocked case CS130. Here's a paper to aid in the installation.

http://photos.imageevent.com/durango...%20Install.pdf

On a final note, those six speakers will probably have a hard time playing well with one another. In a cabin the size of a C3, you really only need a good solid front stage. The front speakers you picked may not be best suited for solo duty in a lout open air car like a Corvette so adding some rear speakers will definitely help. I would however, try to talk you out of using the third set of speakers.

Put the pair of larger more powerful speakers in front, and the smaller less powerful speakers in the back. Amp them, and call it a day.

 

A x V = W

 

Would it better to put 200-400w 4x6's in the front instead of what I have now to equalize with the rear 6x9's?

 

I know I'm stepping on toes with this response [and probably hijacking the thread]...but I just can't help myself. I used to play in a rock band...bass guitar. We played big halls and I had a 100 watt amp head pushing two big speaker cabinets with 15" JLB's. I had a buddy with an electronics lab and one day we checked out the power output of the amp through its volume range. It really did put out 100 clean RMS watts at max. volume, but it turned out, at normal volumes in a good sized hall, I was probably putting out a true RMS power of less than 10 watts and it was plenty loud. People buy these HUGE power monster car stereo systems for big buck$ and I'm just stunned. For the sound purist, you can get great sound quality with a higher power system than you really need, but that just generates clean sound on power pulse bass sounds...which is great! But what's with the 300, 500, or 1000 watt thing? And this is NOT a rhetorical question....I'd really like to understand why anyone would want to do this in order to [personally] listen to music. Now, if the real goal is to play music for the whole neighborhood.... D_boy, what's the attraction?

 

7T1Vette, I'm not into the huge boomers, or am I trying to hold a mini concert from my car for the people on my block. I went to a stereo store and they told me these speakers would sound nice for my Vette, and I was told an amplifier would just make them sound better. If these will sound good without an amp, then I'm happy. I never understood why people would put tons of money, and power just to listen to music in a car....but everybody has different taste in stereo equipment. I just want the front and back speakers to sound good together, and not because they're the loudest on the block . Thanks for your opinion

 

I got a 22w per channel head unit driving 4 - 6" speakers,, 2 in the front in the kicks,, and two in the rear as subs, in a box. The sound is plenty good for just cruising around with the T's out. Incedently,, the Max power rating is a MEANINGLESS NUMBER. what counts is the RMS or Continous Power rating in everything,, that's what you experience and that's how devices trade power in real time.
Used to be, the manufacturers would simply rate the speakers or amps at twice RMS and call it peak,, but now they're hiting them with the max power it can survive, it looks like, and putting it on the box as some real rating. max power. Meaningless. My 30 watt RMS Pioneers were rated at 120 Watts, peak, real big, on the box. in the fine print,, or specifacations it says 30W RMS. Allways ask what the RMS or continous power is, and build the system around this,, anything else is pure fantasy. Some of those stereo sales people don't know thier ykw from a hole in the ground,, so allways check the box before you buy for RMS power rating,, esp on Amps. Also check what Impeadenmce a power amp delivers it's power to. sopme will be 4 ohms, some will be 2,, some older ones will be 8, 8 used to be the standard,, now it's 4. That's important because if you go with twice the rated resistance (same as impeadence)in a speaker, the power you will get out is only 1/4 the rated power.
eg: If your amp says it delivers 200 watts into a 2 ohm sub and you hook up a 4 ohm sub you get,, that's right, 50 watts of power out of it. nothing you can do about it either. just bear these facts in mind,, i'd say that 75 clean watts of power into each of 4 speakers would be plenty good enough for even the most jaded listener,, and will sound great if you use quality componants and position them right.

 

Yes. You want the bigger better music coming from in front of you. In such a small car you really don't even need the rear speakers but you already have the equipment. Run the 6x9" speakers in the back. Use a smaller 4 channel amp, no bigger than 75 watts RMS per channel.

Let me know if you would like some help choosing an amp.



Easy. say some kid just got himself a Honda Civic, a wong, fart can, and a few stickers. He walks into Wal-Mart for his stereo equipment. Do you think he's going to buy a set of Boston Acoustic 6.5" 75 watt speakers or will he purchase the Sony Xplode 6.5" 300 watts speaker set for $40 less than the BAs? It's all marketing. They know that by slapping a huge wattage on a low quality speaker they will sell more even though they are rated at the same RMS wattage.

 

Wow, I actually know the answer to a question posted on this forum. I am a bass player (my moniker refers to the Geddy Lee signature Fender Jazz bass). I think the major difference between a stereo system in a car and your bass rig lies with the speakers. Power is power and it doesn't really matter where it comes from (in theory), but it matters greatly what it is played through. Sensitivity ratings (dB at 1 meter per 1 watt) for a car speaker would vary greatly depending on the application (volume of the enclosure, harmonic of the cabin, etc.). That said, I'm sure the sensitivity of a car speaker in a car would not be as great as a bass amp which is more akin to a loudspeaker than a high-fi full range audio speaker like in your car. SO, due to the difference in sensitivity of the speakers, more power is required.

As an aside, depending on when you played bass, you might have had a tube power section in your amp which can put out its full rated power and sound good. A solid state amp pushed past clipping is not pleasing to the ear and most solid state amp begin clipping well before their max power rating.

Speaking of power rating, I also think that many current amps have inflated power ratings. Even though an amp can make its max power, if it can only do so for a moment before releasing the magic blue smoke what good is a max rating?

Okay, that's it. I'm done talking for now.

 

Well, I DO appreciate the responses. Please understand that I have absolutely NO PROBLEM with anyone buying whatever they want...I just didn't understand WHY. {But I DO have a problem with those who want to invade MY music space with THEIR music!} I think you've given me a fair answer...but those JBL speakers were B-I-G magnet speakers which weren't that efficient. Anyway, thanks for the dialogue with an "old rocker" who is now enlightened! [[This program will now return to its original station...]]

 

Just run the 4 x 6's in the dash and the 6 x 9's in the rear. Try them without an amp first. You may be surprised and may not need an amp. I have the same speakers with a Sony 4 x 25W deck.

 

Put and amp in it and upgrade to at least 120 amp alternator. I'm in the middle of that right now along with a new interior. You won't be sorry for all your work. I'll try to send some pics if I can figure out how to do it on here. I'm not real good with a 'puter, better with wrenches!

 

Here, this may help with the picture posting.

http://photos.imageevent.com/durango...g%20Images.pdf

 

7T1Vette, if the truth be told......of your 10 watt output, 1 watt of pure power, in the correct situation, is enough to make your ears bleed. I have played lead guitar for 34 years. You don't need alot of watts to sound "musical" in your vehicle. Clean is the key. I'm in Tucson, maybe we'll see each other one day. I'm trying to finish my 69 to make cars in the park in Sierra Vista Oct 12-13.

 

DurangoBoy, my new hero.....Thanks, Tank

 

Don't thank me, , thank Photobucket.

Most car audio makers thrive on hype. The good quality stuff is almost always going to be a brand you can't find at local stores.

There are premium brands out there that make a $6,000 set of three way components. How's that for sick?

 

I only put the max wattage that the speakers advertized to see what size amp would work best, and if the original electrical system of the car would handle that extra power . I checked the boxes of the speakers and the 4x6's RMS are 40w & 45w. The 6x9's are 100w, and the Pioneer stereo is rated at 50w x 4 . When I installed the 45w 4x6's in the dash I turned on the radio when I had one new speaker, and one original one in, and the new one sounded so much better compared to the original speaker . And I figure they will sound even better with the new Pioneer stereo. I'm also building a custom speaker box for the rear to hold the 6x9's. I'll place pics of the box when it's all done. Thanks everybody for your input on this matter.

 

Ignorance is bliss.

 

How do you conclude that?

 

I can't find the frig'n paper righ tnow, but I recall reading the 10SI alternator had a loaded output of around 32-34 amps at 800 RPMs. Depending on the internals obviously both the idle output and maximum output would vary.