Need some help guys

[somebody]

Ok well this will probably sound like a stupid question to you guys but whats the difference between running a componet set active and passive? How do you run speakers active? Do you need crossovers to run active?

[wakibaki]

Anything that's got an amplifier in it is active.

You can have one amplifier (per channel). You can run one speaker off this, or you can run many. If you want the speakers to handle different frequencies, as is common, you need to split the signal after the amp. This requires a device which, since it contains no amplification, is called a passive crossover.

You can choose to have more than one amp per channel e.g. one per speaker. In this case the signal will be split into different frequency bands before the amplifiers. You can do this with a passive network, but often some amplification is done at this stage, to overcome the losses in the filter, and because at small signal levels it makes the design less demanding in some ways, and because the power levels are small.

If the active/passive distinction is applied to other parts of the chain, it generally reflects the above principle. An active speaker has the amplifier built in.

You could find out most of this stuff without a lot of effort by searching on this site or on google...

w

[RobWells]

Because you said 'component set' I'm assuming you're talking car audio..

A common generalisation is active will be better, but you will need an active crossover and an extra amplifier.

IMO it's only worth considering after you've done all the basic things first. - sound deadening, positioning tweets properly etc.

Also I'd think it would be really difficult to set up an active system without decent measuring gear - A passive system could easily end up sounding better than an active system set up 'by ear'


Rob.

[somebody]

Originally posted by RobWells
Because you said 'component set' I'm assuming you're talking car audio..

A common generalisation is active will be better, but you will need an active crossover and an extra amplifier.

IMO it's only worth considering after you've done all the basic things first. - sound deadening, positioning tweets properly etc.

Also I'd think it would be really difficult to set up an active system without decent measuring gear - A passive system could easily end up sounding better than an active system set up 'by ear'


Rob.

Correct, I am talking about car audio, sound deadening and all the other basic stuff is done, could someone please explain how to wire the system and give a few suggestions about the which crossovvers would work good for me. The componets I have are CDT Eurosport 6.5"-4" 3 way set and I bought them used and the original crossovers were not included so I need new crossovers anyways. Here is a link to the componets if it helps any except instead of the DRT-26 tweets I have ES-01 tweets. Thanks for all the help.


http://www.buycdt.com/es642i.htm

[RobWells]

1st thing to do is e-mail CDT and ask them the crossover points and the order of the slopes for your component set. After that you can then search for a suitable 3-way active crossover.

Some head units have active xo's built in, but not much flexibility in the ones I've seen.

You'll also need 3 stereo amps to run them active, plus another amp for your sub/s.

I'd personally be looking at around 150 RMS for the midbass units, around 75 - 100 RMS for the midrange and about 30 - 50 for the tweeters.

Basic install would be :

Head unit -> active xo - > amps -> speakers. To maximise the signal to noise ratio you'd need someone to scope the system - basically measure at each point in the chain to ensure that no clipping is introduced into the signal.

Rob.

A good primer for car audio is here

[Cal Weldon]

Moved to car audio.

[jol50]

I would get a good HU. The cheapest I found is the Pioneer 880 on US ebay for ~200 right now. It will do it. You can do it with amps if you have one that band passes the midrange, but then you give up front seat access....unless you buy a 3 way crossover and you need a good one or they are noisy. Then you need a big EQ.

If you get the HU like the 880, it has a huge EQ (and DSP) in it and comes with a mic to do a basic auto RTA of your car to see where you are at....then you have something to work with on your own. There is a good clarion that will work, alpine and eclipse also can do it as well as some even better combo packages. With the EQ, time alignment, and the mic you can get it tuned in much better than old style huge EQ in the trunk, and then have to RTA it manually (that most people don't have).

[somebody]

I have a pioneer AVH-P5000 h/u and a clarion 7 band seperate equalizer, the h/u should be good but will the eq even be nessacary if im going active?

[somebody]

Originally posted by RobWells
1st thing to do is e-mail CDT and ask them the crossover points and the order of the slopes for your component set. After that you can then search for a suitable 3-way active crossover.

Some head units have active xo's built in, but not much flexibility in the ones I've seen.

You'll also need 3 stereo amps to run them active, plus another amp for your sub/s.

I'd personally be looking at around 150 RMS for the midbass units, around 75 - 100 RMS for the midrange and about 30 - 50 for the tweeters.

Basic install would be :

Head unit -> active xo - > amps -> speakers. To maximise the signal to noise ratio you'd need someone to scope the system - basically measure at each point in the chain to ensure that no clipping is introduced into the signal.

Rob.

A good primer for car audio is here

Do you really need 3 amps or could you use 1 multichanel amp? I already have a sundown sax-100.4 that puts out 100rms X 4 at 4ohms.

[jol50]

Multi ch amp is fine. You can adjust the crossover points....but you still can only do that and vary the gains of each amp for highs/mid/lows. So if say your mid gets loud in the top of its range, you would need an EQ to get rid of that. But you need a big EQ with many bands, or a parametric so you can zero in on that spot.