If your amp can handle a 2 ohm load then yes you can run the tweeters and 4 inch speakers off the amp. Make sure that you have the crossover set high enough to filter all bass out. The speakers can't handle anything but midrange.
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sparky
While it can be done, I'd recommend a decent 4 inch coaxial speaker to go in the dash. Dash speakers are usually pretty bright anyways, and I don't see the need for adding tweeters.
If you do go with your speakers, make sure the tweeters come with their own crossovers (if they're in an add-on set, they usually do). Also, find out for sure what the rms rating of your 4 inchers are, then use a multimeter to set the gain to that level. If you're unsure, use the search function in the upper right hand corner, and you should find everything you need.
If you've got a 4 channel amp, are you bridging two channels to power the sub, or do you have another amp for that? The reason I ask is because if you are using another amp you can just use one speaker per channel- two for the 4's and two for the tweets. You must have an outboard crossover for the tweeters, though, because many amps usually don't have crossover points high enough to run just tweeters.
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My ex once told me I have a perfect face for radio.
The tweeters do have their own crossover network. The four-channel amp will power two front and two rear channels. The sub is powered by a dedicated mono amp.
According to the tweeters' manual, one simply connects the positive and negative terminals of the tweeters to the positive and negative terminals of the full-range speakers. Does that make the total impedance of the combined set 2 ohms? My amp can only deliver the full frequency range at a 4 ohm impedence.
What should I connect to the front-channel output of the amp - the tweeters (50W RMS input) or the full-range drivers (+- 20W RMS input)? Logic indicates that I can connect the tweeters to the amp (which the tweeters' manual indicates one can do), with the full-range set running directly from the head-unit. Or can I connect both the tweeters and full-range speakers to front two channels on the amp?
Incidently, the tweeters' wiring diagram indicates that one can connect both the tweeters and full-range speakers to an amp. It's Kenwood tweeters, so I doubt if the company would supply an incorrect diagram...
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F R A N S
1985 Mercedes-Benz 230E
320 000 km / 199 000 miles
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I'm confused as to what you're working with. Basically, a tweeter and a midrange should be designed to be used with each other by separating them with a crossover that was designed particularly for those drivers. If you have drivers that are intended to be used with each other, go ahead as planned.
It is the crossover network that is attached to the mid, not the tweeter. The signal goes to the crossover and is separated by frequency to the two drivers. If each of the drivers is nominal 4 ohm, the overall impedance will stay at 4 ohm because of this separation of frequencies. You don't have to worry that you are lowering the impedance.
This tweeter/midrange network will now be thought of as "one speaker", because that is what the ultimate function is. So just use the front two channels of your amp for the pair.
The "full-range" driver is now no longer full range...it is a mid driver. The crossover should be separating these drivers at about 3.5kHz, but that would be taken care of in the design of the crossover. And again, if these two drivers were not designed to be used together with the tweeter crossover you referred to, you should go another route.
And FYI, the amp has specifications based on a 4 ohm impedance load, but it will deliver the full frequency range into any impedance load. For example, you can run an 8 ohm load and the specs will be improved. Conversely, you can (probably) run a two ohm load and get a deteriorated, but still full range, output.
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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.