# Active vs Passive Crossover



## SciontCGuy (Aug 29, 2015)

I was at a local car audio shop recently and starting talking to one of the sales people. Since I'm still new to car audio, I asked him about active vs passive crossovers. He said that, to him, active crossovers aren't worth the money because manufacturers have already tuned their passive crossovers to the optimal frequencies. What do people here think about that? I'm not trying to beat a dead horse as I know there are a lot of threads on here about active vs passive, I just haven't heard this argument before and was wondering how to counter it.


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## Bayboy (Dec 29, 2010)

That's a broad stroke he's painting with. In some instances, yeah the passive has been maximized, but often places limitations on where the separates can be placed from each other to keep that integrity. 

The key to active is not what is often preached (take that passive set and go active) though it can have it's merits over a poorly designed passive crossover that comes with the set. The real key in active is not being constrained to shelf component sets. You can mix & match drivers to suit your tastes & install which opens up doors to various drivers not found in any car audio shop and often of better quality for the same dollar. 

That's the gist, plain & simple.


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## vwdave (Jun 12, 2013)

Well they are two completely different animals. Active is before the amps and passive is after. Running a system active has its benefits, as does passive.

Active: you can optimize the frequencies to your liking. Everyone likes their sound a little different, and usually there's enough overlap between the mids and tweeters that you can play around in the overlap to make it sound best for you.

You also can have better control over how much power is going to each speaker. Passive crossovers rarely have more adjustment than +3,0,-3 dB on the tweeter. You also tend to loose some power when using a passive crossover, not the case with active since it's before your amplifier. You can also run a line driver to increase signal voltage before your crossover to make sure you don't loose anything.

Passive: easier to set up as you just wire it and go. It's also safer, meaning it protects your speakers from turn on pops or odd ball noises that can creep through. It's also idiot-proof (although nothing is completely idiot-proof).

I've run both, I'm currently running active and I have no plans to ever look back.


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## gijoe (Mar 25, 2008)

A passive crossover is built with specific drivers, locations, and angles in mind. No matter how good the passive is, if the speakers aren't arranged in the same (or very similar) manner as they were during the design phase, the crosser points and slopes immediately become less than ideal. 

An active crossover allows a flatter response through the crossover point in more situations, allowing for much better potential, and allowing the user to place speakers where they can fit them, at the angles that work, and still tune for a flat response through the crossover region. 

In short, a good active crossover will always be better than a good passive crossover. That doesn't mean a system with active crossovers will always be better, since it's necessary for the user to tune it, and if they aren't good at it they can make things even worse than a less than ideal passive crossover. Active crossovers are better, but only if you know how to use them, otherwise use a great passive set and save the time and money that it would cost to install, purchase, and tune an active setup.


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## gstokes (Apr 20, 2014)

There is no signal loss with an active system, the active crossover is self powered so as the signal travels through each component in the active crossover it doesn't lose any amplitude whereas with a passive crossover the signal is reduced a little bit as it passes through each component in the passive crossover..

5-channel amplifiers with a bandpass filter are ideal for 2-way active plus subwoofer setups, that's what i find attractive about 5-channel amps with BP, they negate the need for a discrete active crossover upstream of the amplifier..


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## Alrojoca (Oct 5, 2012)

The shop is correct for the most part, a passive filter is made for the drivers or the drivers are made for the passive filters.

In order to use those drivers without their passives, you will need to match all the passives crossing points, slopes etc. Many times that information is not available, and we may just be guessing, If you have a powerful DSP with a wide range of frequency choices and slopes, the active filter will do the job and sound better, one thing to keep in mind is that with an active filter you use one Channel per tweeter and midbass driver that separates power for each driver and offers more clarity due to the separation. 

If you can use a passive where you can use one channel per each driver then the sound differences may not be noticeable. The only benefit of the active filter is as it was mentioned, cleaner power, less resistance and heat that the amp may have to take and probably also the speakers.


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## SciontCGuy (Aug 29, 2015)

Thanks for all your responses! I see how beneficial it is to run active over passive. Another quick question though. I want to get a DSP as well, but I only have the budget right now for that or an active crossover. Which should I get first?


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## Alrojoca (Oct 5, 2012)

Many choices ranging from $250 to over $700.


Do you need 8 channels for a 3 way and sub front?


If not I would just spend $250-400 on an HU that offers active filtering.

The PIo 80prs, or PIo AVH ending in 700 double dins offer active network with decent choices for active pass, you want a unit that has HPF and LPF in the main 4 channels. If using a basic 2 way front and sub system. They offer,basic time alignment EQ and decent processing for good SQ


If you want a 3 way front and sub, then the PIo P99, or external DSP. For easy controlling without a lap top, the jbl ms8 and Alpines, the rest ( mosconi, audison, helix, Ppi RF 360) need a laptop for the settings and to save them, and be prepared to deal with 31 EQ bands per channel and spend hours if not months to get it tuned properly, an RTA Amy help to get started, all things add up, unless you have the time, you may want to get hands on help from members of the forum if you are lucky, or search for a pro also here that can help you tune your system properly.


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## Theslaking (Oct 8, 2013)

To answer your question of importance (DSP or crossover) with opinion. I always figure out what signal processing I will be using before I set the rest. If you have a HU with great processing then a DSP may not be necessary for your application. In that case get whatever crossover you want first. If you need more adjustability the your HU can offer then a DSP should definitely be first.


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## sqnut (Dec 24, 2009)

SciontCGuy said:


> Thanks for all your responses! I see how beneficial it is to run active over passive. Another quick question though. I want to get a DSP as well, but I only have the budget right now for that or an active crossover. Which should I get first?


It's not one or the other. All dsp's will give you the ability to set active networks. Choose one based on how many channels you need and your budget. 2 way + sub = 5 channels, 3 way + sub = 8 channels.


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## cajunner (Apr 13, 2007)

cheap passive crossover component sets do not have really great optimized, or voiced crossover duties covered.

expensive passives have a lot of adjustments and built-in equalization at the passive component level, which make sonic improvements that a DSP would also be able to match, most of the time.

if you put an active crossover into a suite of drivers that had a minimal passive crossover come with the set, you can realize good gains in sound quality using just the active crossover, but a DSP always has the time alignment function, which is where you pay extra for the service.

a bare-bones active crossover, used on a great set of drivers may be all you need, but it will depend on placement in the vehicle for the percentage of success you enjoy.


most people will move along in their build to add a DSP since that's the basic entry level point for the hobby where you can begin competing and tuning and doing all that fun stuff like measurements and graphs and the assorted hardware necessary to complete, or look towards a horizon with it's finish lines always gradually receding in the distance...

but as advice goes I'd use the passive first, see how you like the sound, decide what it is for that you are buying an active crossover and extra amp channels, and/or a DSP.

Get out to some stereo shops and see if you can demo the difference between active and passive, find out what people mean by crossover selection, and why passive can be pretty awesome especially if you can bi-amp using time-alignment built into a deck's suite of filters and controls.

there are some systems out there that could be stripped down to a 3-channel amp and because the things are all "right" acoustically, or install location-wise, you will hardly notice the improvements over the passive networks and a sub using several amplifiers and a DSP as the system grows more complex and unwieldy and requires actual knowledge to improve using relatively expensive hardware for measurements, and software for all those "ripples in the pond" that an active system has with it's several drivers.

Of course, it's not as fun if you get it to sound "great, er... good enough for me!" using a single amp on highs and a deck's built-in active crossovers, and the passive crossovers in the component set.

It's kind of like when you pay out-of-state hunting fees, licenses, permits, tags, etc. and save up for a few months to make a great trip with some friends, and ten minutes after you set up camp the afternoon you got there, and walk towards a clearing an 8-point buck steps out and looks at you while you shoulder your rifle and take him down...

you just have to continue hunting, even with a chest of meat already sent to the sausage-maker, because well... you put in the effort. That's what you do, haha...


and for all those sensitive types, no animals were actually hurt in this post, since it's an analogy, right?

I mean who would buy all those doo-dads and gadgets and spend weeks to learn how they function, if you could be happy with a normal installation using good product...


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## Staffordshire (Oct 1, 2011)

active is more expensive because you might need more channels, more amps. also you will need to have some knowledge about slopes and frequencies. if you are advanced and have some spare cash then i would go for active.

pre build as said before would be idiot-proof. all the cut off frequencies and slopes are pre set so you will be less likely to blow your speakers. if you will be building your own passive then you will need lots of parts to play with and that is pricey aswell. also it is not easy to build a crossover it will take some time until you find slope and values that you like.

all in all- if i was building a higher end setup, i would go active, if i wanted to go cheaper then passive/hybrid would be the way.


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## Bayboy (Dec 29, 2010)

What's passive/hybrid?


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## Staffordshire (Oct 1, 2011)

Bayboy said:


> What's passive/hybrid?


sorry i meant to say active/passive that would be hybrid. and cheaper


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