tweeters, ohms, and my head unit?

[jordan.guess 1]

So I am struggling on choosing a tweeter that's going to fit my head units power capabilities, and if the ohm load that the tweeter is will majorly affect my vehicles audio performance. My favorite tweeter that I am looking at is 8 ohms, and RMS's at 50 watts with a 1300-20000 frequency range, but will this tweeter perform fully off my deck if its asking for 50 watts at 8 ohms? another tweeter RMS's at 15 ohms, but has a 4 ohm impedance with a 3500-25000 frequency range....would i be better off with this because it more matches the RMS wattage of my head unit? lastly, I found another tweeter that surpasses all others in that it is 4 ohms, but requires 100 watts RMS....would the power of my deck even be able to make two of these perform well? not to mention they are twice the price, and idk if i would want to do that If one of the 8 ohm tweets, or the low RMS 4 ohm tweet would better suite my needs.

Also, at what frequency range will you no longer see in music? is 25000 a little over the top? or is it not enough?...your help is much appreciated, thanks!

I avoided labeling titles of tweets so that I could avoid a vs. thread.

[An-i-no 86]

I can say this. If you like music as much as I do, then NOTHING on head unit power will satisfy you. Seriously. And a HU at 8 ohms....will not sound good, sorry.

I don't mean to tear you down, but what you're asking for just screams "buy an external amplifier!"

[jordan.guess 1]

So i would be okay at 8 ohms if i am at external amp, but if im at head unit with speakers requiring low RMS...go head unit?

[An-i-no 86]

So i would be okay at 8 ohms if i am at external amp, but if im at head unit with speakers requiring low RMS...go head unit?

I'm not entirely sure what you mean but maybe this will help.

There's a lot more to sound than output power. An external amp will have a better dampening factor (cone control) and since the HU isn't responsible for being an amplifier AND a processor it will put out a cleaner signal itself (because it's not being pushed to it's limit).

Remember, an 8 ohm speaker is twice as hard to drive as a 4 ohm one so don't think "oh, at 8 ohms the head unit will barely be working," because it's working just as hard but the load is heavier. An external amp will pretty much be better than a head unit (at amplifying) in EVERY way. Plus you can get a small, 4 channel amp for around $120 if not cheaper that will do the job well.

There really is...no good reason to use your HU as an amp when you have the option to get an external one.

Edited June 17, 2012 by An-i-no

[jordan.guess 1]

alright awesome, thanks!

[BKOLFO4 29]

Remember, an 8 ohm speaker is twice as hard to drive as a 4 ohm one so don't think "oh, at 8 ohms the head unit will barely be working," because it's working just as hard but the load is heavier.

That logic is not true.

The radio or amplifier will have the same voltage output on both loads, but the output current on the 8 ohm load will be half of the current on the 4 ohm load.

The radio will NOT work as hard and will only provide half as much power with the 8 ohm load.

If you plan on using tweeters on the headunit, you need to be more concerned with the sensitivity rating of the tweeter more than the max RMS. that is how loud the tweeter is with 1 watt input.

Also keep in mind you need a tweeter with a passive crossover, or you will have to build one (on 20 watts, it can be as simple as a cap).

We use tweeters directly on the headunit all the time and it works great.

Edited June 17, 2012 by BKOLFO4

[An-i-no 86]

Remember, an 8 ohm speaker is twice as hard to drive as a 4 ohm one so don't think "oh, at 8 ohms the head unit will barely be working," because it's working just as hard but the load is heavier.

That logic is not true.

The radio or amplifier will have the same voltage output on both loads, but the output current on the 8 ohm load will be half of the current on the 4 ohm load.

The radio will NOT work as hard and will only provide half as much power with the 8 ohm load.

If you plan on using tweeters on the headunit, you need to be more concerned with the sensitivity rating of the tweeter more than the max RMS. that is how loud the tweeter is with 1 watt input.

Also keep in mind you need a tweeter with a passive crossover, or you will have to build one (on 20 watts, it can be as simple as a cap).

We use tweeters directly on the headunit all the time and it works great.

Oops, my bad.

[///M5 2,833]

I don't understand most 4 ohms drivers. The trade-off's to make them are counterproductive.

More importantly here though is how are you crossing said tweeters over and what are you mating them with? Just buying tweeters and hooking them up to what you have is bad. No questions needed for that, but if it is to mate logically with something and you have processing then it could be fine.