Active vs passive crossover


I think most of forumers in this plaftorm know what are active/passive crossover (essentially crossover before/after the amplification) and understand the pros and cons of them.  Some if not all might even agree the best sound reproduction solution is active crossover with DSP.  But, my question is, why the vast majority of companies in this industry still chooses the passive route.

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"Best sounding" is not how I would universally qualify passive crossovers.

Complexity and the desire to avoid an extra A/D, D/A conversion step are important negatives.  If I am the type to want to go out and buy a fancy DAC and amplifier I don't necessarily want to have the sound quality interfered with by another component I wont' be able to evaluate as thoroughly.

I think it mostly comes down to how much more it would be to make them active and would the normal audiophile be prepared to pay for it.

Money and the ability to blow up their drivers, with our screw ups. The tech support lines would never shut up.. I could see the warrantee lines, behind, OOPS! and expect the manufacture to pay for their messing around. I could hear the conversation. I don't know, it just started smoking and quit working.. :-)

Regards

Grrr, "best sounding is not how I would universally classify ACTIVE crossovers."

@erik_squires 

"best sounding is not how I would universally classify ACTIVE crossovers." I got this part.  Maybe you had experience (A/B comparison) with it and I am not going to dispute that.  But why the complexity and the desire to avoid an extra A/D, D/A conversion step are important "negatives?"  Why does that become "negatives"? I thought being able to avoid A-D-A in the passive crossover greatly helps preserve the quality of signal.  Maybe you know something that I don't...

Of course, active crossover systems, because they utilize two or more amplifiers are much more complex, and require more careful engineering and component matching to pull off properly.  When done right, they can be quite good.  These days, one is tempted to go fully digital-- use DSP to not only accomplish driver crossover, but to also apply room correction, driver correction, etc., all in one step.  I have heard such systems, but none that really bowled me over (that is not to say that the DSP was the cause of any sonic issues).

The closest I heard to an apples to apples comparison occurred MANY years ago.  I head the Advent Loudspeaker and the powered version of the same speaker (same drivers, same internal volume cabinet, but one with active crossover and built in amps) in a direct comparison.  I could not believe that these were similar systems-- the powered version was so much more alive and engaging.  

Hi OP,

Sorry for the short hand. A/D was short for Analog to Digital, and D/A was short for Digital to analog.

These are 2 new steps which must be introduced into the chain for active digital crossovers. Question is, how do I evaluate the sound quality of each step and decide if I like it? Well, I have to listen to the finished product.

With a few decades of experience listening to a variety of great measuring DAC’s I know that some great measuring DAC’s sound like crap.

On paper, if all sounded great, and all A/D and D/A steps were perfect then the active digital crossover offers a number of advantages vs. passive but it’s not necessarily simpler. Now I must deal with multiple amplifiers per speaker. Does the speaker maker pick those? Do I?

My point is definitely not pro or anti either approach. My point is that in practicality there are a number of complexities and trade offs which prevent blanket statements about the superiority of either approach.

 

But, my question is, why the vast majority of companies in this industry still chooses the passive route.

Cost and simplicity.

+1 russ - With passive crossovers, it's much easier to protect the drivers too. I don't use any components between the drivers and the amplifier outputs, just wire. Somewhat risky for the drivers, but worth the risk for the sound improvement to me.

@fiesta75, can you install in-line fuse to the wire if you concern about it?  Might need to be selective with the quality of fuse and holder.  I have not tried it but some people bypass the fuse in the passive crossover and get the speakers to sing with more clarity treble and tighter bass. 

Passive crossovers can get pretty expensive, so I'm not sure how much of the decision comes down to cost with the higher end speakers.  Passive crossovers give the manufacturer full control of the crossover interaction once the speakers get into the end users hands....not so much with an active crossover.  

In term of the cost and simplificity of the architecture, I respectively disagree with the passive crossover system is the lesser of the dual when it is applied in the industry. Think about it, the active crossover/DSP/EQ unit has been multi-channel ready and could house, say, 3-way (6 channels) plus subwoofer, in one-box IF the internal DAC is in Hi-Fi quality. This will eliminate the need for the multi-channel DAC module. Also, as an additional benefit, the DSP/EQ module enables one to perform room acoustic correction.  You would need purchase and add that into the passive system.

When it comes to amplification, the multi-channel PAs can be customized based on the customer’s need just like Emotiva does. Even you have preferences in terms of selecting different PA for each signal frequency spectrum, the power requirement of each P.A. would no longer necessarily be as needy and costly as a single PA serving the full-range frequency. For example, a good 20-30 watts PA should suffice to drive tweeters (2/5kHz - 20 kHz) to sing sweetly. A good 50 wpc and >100 wpc class A/B or D should be prenty to drive midranges (200Hz-2/5kHz) and woofers (40Hz-200Hz). The amplication modules do not need to be manufactured by the venders and, instead, purchased by the individuals to their satisfaction as long as they meet the specification. Note that, in today’s high-end Hi-Fi world, it is quite common that audiphiles purchase expensive monos or multiple stereo amp of enormous power to support their full-range speakers already.

Finally, when it comes speakers, as you know, they just need to be wired directly from the PA at the multiple terminals. If you are concerned about lack of protection then adding in-line quality fuses to the wires or terminals should resolve the issue. Therefore, overall, I really do not think the active crossover system will necessarily be more costly or complex than the passive couterpart. It is just the matter of taking paradigm shifts in concept, implemention and business models to make it reality. I am confident that, if you build it, "they" will come.

All fuses degrade sound. You never want a fuse in series between the amplifier and speakers, ever.