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How much amplifier power is lost by using passive crossovers supplied with the speakers?

I hear people say run active instead of passive but, I wonder would I gain 1db, 2 dbs... 10dbs?

I am already bi-amping my 3-way Focal K2 Power 165KRX3 (with 150w x 4) of an Arc Audio 1200.6 xDI but, I am still using the Focal passive crossovers on all 3 speakers.
 

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I can't, like the previous responses, fully address your question in that I'm not sure how much power reduction you'll experience by using passives. You could certainly test active vs passive with an SPL meter to determine the difference in volume. But even so, you're gain structure would likely be different in one vs the other, so I'm not sure the results would be that accurate, without ensuring all things equal (i.e. equal power output in both scenarios).

What I can say, as the other previous posters stated, is that utilizing active crossover vs passives will result in a profound improvement. I don't believe it's all attributed to not having power "absorbed" by passives either. Each driver's crossover parameters are much more precise, in that they don't change/fluctuate with changes in impedance, phase, temperature, etc. Active sounds much cleaner and level matching is much simpler.

I've been running fully-active systems exclusively since 2004 and wouldn't dream of going back to passive design.
 

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i went active amd went right back to passive.
My amp does 150x4 or 300x2.
300x2 sounds a lot louder and more dynamic on the passives than 150 per speaker. im lucky though. the stock locations for my tweeters arw almost exactlt the same distance away as my mids.
 

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With either passive or active filtering you are taking out( aka attenuating) a range of frequencies. If anything by going active, you reduce the stress on the amplifier by limiting the frequency it needs to do its job.
The other way of looking at it is what power are the passive components using from the amp? I can't imagine a capacitor is providing a load but they do have ESR. Inductors, on the other hand all have DCR (aka some kind of resistance) which is usually in series with speaker impedance. This is in the 0.2 to 0.5 ohm region. So going active for a 4 ohm speaker this would be a 9% decrease in total ohms, thus power. Yes, its a gain in output, just not enough to notice to much especially considering the logarithmic nature of amps.

<post too soon>
The reason you want to go active is flexibility in changing frequencies (passives are usually fixed) and most of all, steeper slopes than passives. These days going DSP, even the less expensive ones, just for active cross over is reason enough to get one.
 

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Not much really, not considerable db increase, and your tweeters will be leveled matched with you midrange and woofers without the hassle and hours trying to level match them by ear going active, in fact you will have to reduce the midrange and tweeter output a lot to get the balance of a passive bi ampable crossover.

The benefits of an active system will come more with better time alignment and EQ per side, perhaps more flexibility to choose more precise x points and slopes.

Better stage, a more centered dialed one seat stage. A better listening experience that only some trained ears can detect or learn to do so.

Will it be worth it? It depends, a 2 way system maybe, a 3 way system will be way more difficult to tune level match and EQ.
 

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1) How much amplifier power is lost by using passive crossovers supplied with the speakers?

2) I hear people say run active instead of passive but, I wonder would I gain 1db, 2 dbs... 10dbs?

3) I am already bi-amping my 3-way Focal K2 Power 165KRX3 (with 150w x 4) of an Arc Audio 1200.6 xDI but, I am still using the Focal passive crossovers on all 3 speakers.
1: Not much

2: Mostly one gains better control over the speaker, in terms of damping in the cross over bands. As well as options to run different size/type of amplifiers to each set of speakers (tweeters, midrange, woofers.). As an example one could run a 50,100 and 200W respectively.

3: An active cross over is easier in terms of changing cross over points.

Any active cross over will out perform a poorly designed passive.
But a lot of work can go into a passive cross over. If it sounds good and you are happy with it, then I would not see a good reason to change.

If one is mixing speakers and needs to alter over cross over points, as well as channel gains to make up for differing efficiency, then it becomes more like a mandatory need.

You probably do not need an active cross-over. You may want one, and there may be reasons to want one, but raw volume is generally not one of them, unless the levels get high enough that 3 amps are needed where one cannnot reach it.
 

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Really depends what you call a passive as you get generic run of the mill passives and then you get passives like the Focal Crossblock

I have heard a active kit 7 and compared it to my passive kit 7 - I can say the passive was not worse than the active.

But most of the passives these days are convenience devices and not purposely designed tools to aid the final solution

Only the passive in the Uber high end speaker sets are worth using imho

Otherwise a DSP would work great with or without passives in your system

I used the crossblock and DSP in my car...


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Another point. If you like how it sounds now, leave it. If you want better, you're entering the tinkering stage. This stage is limitless. For me, personally, it's a hobby. I'm swapping amps when I get new ones. I'm comparing them. I have different branded tweets and mids. A passive xover is not an option for me, as per previous posts' s point on mixing drivers. And the point of different quality passive xovers is a good one too. A properly designed and built passive xover is pretty good to use. And as for power loss.. There will be some, but almost negligeable really. I've also seen passive xovers get burned from being abused... Can't do that with active setups... You will burn drivers instead :). So. Tinker. Or install and forget about it. 2 different types of audio listeners.

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Another point. If you like how it sounds now, leave it. If you want better, you're entering the tinkering stage. This stage is limitless. For me, personally, it's a hobby. I'm swapping amps when I get new ones. I'm comparing them. I have different branded tweets and mids. A passive xover is not an option for me, as per previous posts' s point on mixing drivers. And the point of different quality passive xovers is a good one too. A properly designed and built passive xover is pretty good to use. And as for power loss.. There will be some, but almost negligeable really. I've also seen passive xovers get burned from being abused... Can't do that with active setups... You will burn drivers instead :). So. Tinker. Or install and forget about it. 2 different types of audio listeners.

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The quest for better is an obsession I am well aware of...

But now I'll settle for decent .... to my standards!


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How much power is lostis low, but in reality one can gain a lot more headroom with 3-amps on an active crossover - compared to one through a passive.
 
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