ok, i really dont know much at all about car speakers and when enough is enough, or when an amp is needed.

heres what i have right now
Radio - Kenwood KRC 2000A 6W + 6W
2x Pioneer 4x6 TS-A4670R - 120w peak, 20RMS
2x Pioneer 6x9 TS-A6961R - 230w peak, 40RMS

now, i also have another set of the 6x9's laying around and some 4" TS-G1041R 110w peak, 20RMS.

im looking at installing these some time this spring. is this going to be too much of a strain on the radio? will i need an amp? if so, what size should i be looking for?

 

first of all, the peak power ratings mean NOTHING, disregard those numbers completely. The only power specs that are meaningful are the RMS ratings.

second, as long as they are a standard 4 ohm speaker they will not put any strain on the radio. . The power rating doesn't mean a thing to the radio, all the radio sees is what the impedance of the speaker is. BTW, the 4 ohm spec on the speakers is an "average" rating because as the speaker is playing the impedance changes constantly.

If you need is amp is really up to you. if you like to turn it up to above normal listening levels at times an amp will always help. Keep in mind that in our cars, the ambient noise level is relatively loud compared to a modern car therefore to have the speakers at a percieved "normal" listening level the radio is usually turned up somewhat louder to overcome the amient outside noises to hear the speakers at a normal volume level.

any ANY amp, whether it's the very small amps built into a radio or larger external amp, the higher you turn up the volume the harder the amp has to work and the more you will increase distortion levels in the signal to the speaker. It's almost always distortion that blows speakers, not power. The larger the amp is, the power you have therefore to listen to the system at the same percieved volume level. A more powerful amp is working less and therefore putting out lower distortion than a a smaller, less powerful amp. Not only will it sound better, but you have a much less chance of damaging or blowing the speaker.
I can take a speaker rated at 50 watts RMS, hook it up to a very powerful amp rated at over 250 watts/channel RMS power output and play it very loud for a long time and never blow the speaker simply because the distortion levels are so low and than take the same speakers and hook them up to a very small amp such as the one in the radio you listed in your post and I could blow those speakers quickly simply because of the much higher distortion levels even though the speakers are rated to handle an amount of power above which what the radio is actually putting out.

The bottom line is that do you NEED a larger amp? No, the speakers will play fine off the radio, but would you see a difference in sound quality of the system if you added a more powerful amp than the answer is yes you would and besides sounding better with the larger amp it will also typically be easier and safer on the speakers too because of lower distortion levels.

Yes, it IS possible to blow a speaker from too much power also, it can cause a thermo failure of the speakers voice coil from too much heat (more power means more heat to the voice coil) but this is actually much rarer to blow a speaker this way rather than from distortion levels.

think of amps as the motor in a car. a small amp is like a little 4-cylinder motor and a large amp is like a big V-8 motor. when cruising at 60mph in the car, the little motor (little amp) is working really hard and revving up to high rpm's but the big motor (big amp) is loafing along barely above idle and not working hard at all.

If you decide to go with an aftermarket external amp, with the speakers you have, I'd recommend looking into a good quality amp that puts out a power rating of approx 30-40 watts/channel RMS. This would make a significant difference in the sound quality that you hear out of the system simply from much lower distortion levels being introduced into the system and you can turn it up louder if you wish while still keeping the distortion levels relatively low.

Hope this helps a bit.

 

seeing as i really knew about nothing about car radios and amps, that helped out alot.

 

Barry, that was a pretty good explanation

 

glad to be of help

 

ok, ive been doing some reading and searching and have settled on an amp. its a kenwood kac744. 40wx4 @ 4ohm. im going to run my two 4x6s from the exsisting radio, and my 4 6x9s from the amp, and ditch the 4"s.

now ive run into another question, and possible problem. i see all of these amps use RCA cables to go from the amp to the radio. my radio is a kenwood KRC-2000a and has no RCA jacks. it does however have a preout that in the manual says to attach to an amp.

i guess my question is, will this pre-out work or am i SOL with no rca jacks?

 

you can make the RCAs, radio shack has the parts, cheap enough

 

how abouts does that work?

does one end of the cable just plug into the regular +/- jacks and then the other end has a RCA end on it?

 

whatever made you decide to run the system like that??
no way you need 6 full range speakers in the car.
I'd recommend using the amp to run all the speakers, and by all of them I mean only four (2 pairs).
have the amp run the front 4x6's in the dash and also your 6x9's in the rear. That's all you need. Adding a second pair of 6x9's in the rear isn't going to do anything for you other than muddy up the sound, especially if they are different model speakers.
since you have the amp there would be no logical reason to have the radio run any of the speakers directly.........refer back to my previous post about distortion!

Believe me, when it come to audio, the KISS principle is almost always the best when it comes to sound quality.

Regarding the amp you are considering, be aware that's almost a 10 year old amp........
I don't know the specs or the connection hook-ups on that particular model but a lot of amps will accept a high-level input from the radio so you don't always have to have the RCA jacks to hook up an amp. If the amp accepts high-level outputs all you need to do it connect the radio's speaker leads to the input jacks on the amp

 

my reasoning for going this way is...

the 4x6s are currently just about the only audible speakers in the car. the 6x9s are in a cut out back behind each seat, wich makes them almost inaudible.

the new 6x9s will be going ontop of the rear compartment lids, so this way the speakers will almost be right behind my head.

with more power going to the 4x6s, and the 6x9s on there own amp, i may actually be able to hear the radio when im going 60mph.

heres the specs on the amp...


and a friend of mine pointed me towards a set of line out RCA converters that ill be useing.

 

They're probably inaudible becuase the fader is turned all the way forward. Trust me, if those 6x9s are functioning, you'd hear them. I totally agree with the poster above - don't go with 6 speakers. In fact, I'd recommend buying two smaller 2 channel amps so you can control the front-rear fade of the sound.

 

more power to the 4x6's?????
how do you figure the 4x6's are getting more power from the radio than they are from the external amp?

if you do the 4x6's in the front and one pair of 6x9's in the rear, both pairs running off the external amp you will have plenty of sound and volume! This is assuming of course all 4 speakers are wired correctly and working correctly.
if any speaker within a pair or any pair of speakers against the other pair of speakers are wired incorrectly, IE: out of phase, than you WILL lose a good percetage of sound, so make sure everything is wired correctly with the proper +/- speaker leads orientation.


Batman, as long as the radio has a 4-channel output, whether it's RCA leads or high-level (speakers leads) going to the 4-channel amp he will have proper fading and balance control. Running two seperate amps is not needed and will just complicate the install with needing more wire runs and additional room to mount two amps rather than just one. Follow KISS and you will thank me for it, I promise.
I used to do this for a living..........

 

Arrgh...good point about the 4-channel. I used to help a professional installer friend of mine all the time, we almost always used two (or more) 2-channel amps rather than 4-channels. If you use a 2-output fuse/distribution block, it's not much more wiring, but more space is needed.

I stand by the recommendation to stay with 4 speakers.

 

I have a 4-channel fosgate amp and it has seperate gain controls for front and back channels...I thought this was pretty common on newer amps. My head unit only has 2 rca outs(low-level), so this setup lets me still setup the fade right.

 

Have got to agree with BarryK. Keep it simple. We fought the noise battle in our '69 coupe. We now have great sound at 70 MPH w/tops off. 200 watt amp, two 6x9s, two 4x6s(front) and NO electrical noise anywhere or anytime. We have a Pioneer in-dash am/fm CD player. Good luck.

 

looks like ill be sticking with the 4 speakers total. after seeing how many people agree on it, and i knowing very little about the subject, ill take the advice and run with it.

now i get to start that fun new project of takeing that damn radio out of the cluster again...