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Discussion Starter · #1 ·
Ok guys, I have a set of Alpine R-S65C.2 that will be going in the car. I also have an Alpine R-A60F (100w x4 @ 4 ohm) there is more but this is the only piece that has me scratching my head. So obviously this set is a component set with a 6.5 and a 1" tweeter. They are rated at 100w RMS but how is that power distributed. I can connect these two different ways I guess. Place them on the same channel using the passive crossovers that came with them hence splitting the power to 50w to the 6.5 and 50w to the tweeter. or I have the channels available to give them 100w RMS to each piece of the components. I doubt that tweeter is going to like 100w RMS so obviously i would have to tone it down but it would give me the ability to control the crossover actively at the amp. Happy 4th and thanks in advance for any suggestions.
 

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a crossover doesnt split power 50/50

probably like 10(mid) to 1(tweeter)

A tweeter only needs a few watts to get loud.

I would run it all on individual channels. If you have a heaudnit that has time alignment, thats a plus. Because you could run the front and rear preouts to the amp and get the time alignment correct.
 

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I know they don't split power but if I cross them over passively I can connect them to the same channel to achieve 50/50. I do have time alignment.
The amp does not supply 100W all the time... the lowest amount is 0W.

If you are listening to piccolo music it may be 100% going to the tweeter, mist music will have 80-90% of the power going to the woofer.

Pink noise drops off at the higher frequencies just like general music.

If they are on separate channels then it will be around 100W and 15W.
And in an RMS sense more like 5W and 1W (woofer/tweeter respectively.)
 

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Discussion Starter · #6 ·
The amp does not supply 100W all the time... the lowest amount is 0W.

If you are listening to piccolo music it may be 100% going to the tweeter, mist music will have 80-90% of the power going to the woofer.

Pink noise drops off at the higher frequencies just like general music.

If they are on separate channels then it will be around 100W and 15W.
And in an RMS sense more like 5W and 1W (woofer/tweeter respectively.)

I really want to wire them individually. The problem is the set is 100w RMS. There is no info on them as individual pieces so I have no idea what the RMS is for each individual piece. I would assume that the 6.5 could take more RMS than the 1". The problem comes down to the gain on each. Since the tweeters will be on channels 1&2 and the 6.5s on 3&4 I can separate the gains. I am assuming that the gains on the tweeters will need to be practically all the way down though. Which if that is the case I don't know that it makes since to separate them into different channels. If my assumption is correct would it not be better to just add the passive crossovers and connect them both to Channels 1&2? Also at the end of the day is there any reason to separate them into their own respective channels? Maybe I am just overthinking this one.
 

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I really want to wire them individually. The problem is the set is 100w RMS. There is no info on them as individual pieces so I have no idea what the RMS is for each individual piece. I would assume that the 6.5 could take more RMS than the 1". The problem comes down to the gain on each. Since the tweeters will be on channels 1&2 and the 6.5s on 3&4 I can separate the gains. I am assuming that the gains on the tweeters will need to be practically all the way down though. Which if that is the case I don't know that it makes since to separate them into different channels. If my assumption is correct would it not be better to just add the passive crossovers and connect them both to Channels 1&2? Also at the end of the day is there any reason to separate them into their own respective channels? Maybe I am just overthinking this one.
Just set the gain pots all the same... Fully at minimum.
If it is not loud enough then turn them all up.

The tweeters only receive the combo of the signals in the RCS and the gain knob.
They do not "receive" 100W... They could, in theory with a 100W amp, but they never will see that wattage with any known music.

Just hook em up and give it a whirl.
 

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Run them off the 4 channels. The tweeter will not ever see 100 watts.
The gains on the amp...use them to match the levels.
By using all 4 channels you have the ability to give the woofer the power it wants. 100 watts is perfect for the type r midwoofer. It's actually a very nice midbass.
The tweeters will not need that much. But the amp has gains. Use them to blend the mid and tweets to what sounds good to you.
The tweeter xover box also has 2 or 3 jumpers on the inside that will allow you to lower the level more if you want. Just set the gains with the xover set on +2 or whatever the loudest setting is.
Then if the tweets are still a little harsh you can turn them down at the xover or the amp. Which ever is easiest for you.
If your head unit has time alignment using all 4 channels will give you 4 channels of alignment instead of just the 2. Allowing a better blend between the mid and tweets.
The only reason not to is if you were going to bridge the other 2 channels to sub or something.
 

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There has already been some good information in this thread for you. Your amp has the necessary crossovers for you to run active, without the passive crossovers, but if you don't have time alignment, or any other tuning features, then running the components active is not going to give you much benefit over keeping the passive crossovers in place. You will gain the ability to level match a bit more accurately by using the gains, and you'll be able to choose your own crossover point between the mid and tweet, but that may not help much, especially if you just duplicate what the passive crossover is doing.

As mentioned, passive crossovers primarily split frequencies, not power. Although, if there are resistors in the crossovers to attenuate the tweeters, then the crossovers can do a bit of both. The signal going into the passive crossover already has significanly less power on the high frequencies than it does on the low frequencies. If you choose to run them active from the amp, make sure to set the HPF for the tweeters at a safe frequency, or you'll risk ruining them. Sending the tweeters low frequencies will be much riskier than sending them a little extra power with a proper crossover set.

Gains are easy to set. Set the gains for everything to their minimum. Slowly turn up the gains on the mids until you get roughly the volume that you're looking for with the head unit set to 75-80%. Slowly turn up the tweeter gain to get a balanced sound. Take your time with this, and if you hear distortion, back down the gains a touch. Again, make sure you set your crossovers correctly before turning the gains up. The amplifier will not automatically produce 100 watts per channel, it's power output will depend on the input signal's power, and how much of the gain you use. If the input signal is low voltage, you will need more gain on the amp than if the input voltage is high. Typical listening levels only require a handful of watts, most speakers will produce at least conversation level SPL with less than a single watt. Take your time, and make small adjustments at a time. At 75-80% of your head unit's volume range you should be pretty much at the loudest level you'll listen to, with that last 20% reserved for when you really want to crank music that was recorded at a lower SPL than most.

Having said all that, you have 2 options, keep the passive crossovers, which will ensure that the tweeter is crossed over high enough to be safe, and use the build in tweeter attenuation switch to balance the output between the mid and tweeter. Or, run them active from the amp after setting a safe crossover point for your speakers. The passive crossover offers slightly more protection for the tweeters, and running active offers slightly more tunability. Since you aren't running a DSP, running active from the amp won't give you nearly as much tunability advantage, but it would still be a bit more flexible than using the passive crossovers.
 

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Discussion Starter · #10 ·
Below is my setup. As you can see I think I have this planned out optimally but putting another set of eyes on it couldn't hurt. If there is anything you would do differently please leave a comment. You know what they say about best laid plans. Since I decided to do an all Alpine system ( Yeah I know the head unit is Kenwood but the global chip shortage got me so I will address that later) the amp matching for Alpine was not optimal hence why I have two sub amps. However they do match the RMS of the Sub and the birth sheet has them both at 800w RMS into 2 ohms so we should be good. I had to go with an Sealed enclosure because I am going to get the trunk done custom but my local sound shop that has the equipment to do it charges $130 an hour plus materials so I need to get my funds right again after buying all of the below before I go on that adventure. Anyway enough rambling, see anything out of place?

Car:
2011 Nissan Altima 2.5S

Head Unit:
Kenwood DMX7705s

Speakers: 10 Total
R-S65C.2 (100x4 @4 Ohms) Dash and Front Doors
R-S65.2 (100x4 @4 Ohms) Rear Doors
R-S69.2 (100x4 @4 Ohms) Rear Deck
R-W12D4 x 2 (750w RMS @2 Ohms) Trunk

Amps: 4 Total
R- A60F (100x4 @4 Ohms) Dash and Front Doors
R- A60F (100x4 @4 Ohms) Rear Doors and Rear Deck
R-A75M (750x1 @ 2Ohms) Subwoofer 1
R-A75M (750x1 @ 2Ohms) Subwoofer 2

Electrical Upgrades:
370 Amp Alternator
Big 3 Upgrade

Box:
Zenclosures Sealed Box 1.07 Cubic Feet per Sub

Sound Dampener:
Sound Skins - Trunk, Rear Deck, 4 Doors, Headliner
 

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There is no reason to run them active unless your head unit has time alignment. Sure, the passive crossovers will eat up some of the power but not enough to matter, they designed the crossovers for their speakers.

But if you want to run them active there’s no reason not to as long as you read up on settings gains to keep speakers from clipping. But if you don’t have time alignment etc. it’s more effort for little to no benefit.

if you do run them active use capacitors to protect the tweeters (or the passive crossovers they came with), especially if you’re using the amps crossovers; it’d be easy to accidentally knock into them.
 

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Personally I would start with the dash speakers, and the subs, before layering in more speakers and amps.
(You may even have enough gear for 2-3 cars.)
 
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