In a general engineering sense, active (powered) speakers are almost always superior, and they are much easier and cheaper to make excellent than are passive speakers.  The list of technical advantages is long, and I won't go into them here.  

In an argumentative theoretical sense, it is possible for passive speakers to be made to equal or almost equal active ones, if the builder/or user possesses the technical knowledge, ability and test facilities to do the work.  But it's actually quite hard, and very expensive.  

At Sausalito Audio, we never consider passive designs any more, just active ones, for the engineering ease, excellent performance and reduced costs.  

I hope this helps.  

Best regards,

Dave Moulton, Sausalito, Audio

Thanks for that, Dave.

So, to turn the argument the other way around, the majority of passive speakers sold at big discounts by the likes of Richer Sounds might not be that well made or designed if they are being made/ sold at a low price.... yet they will often have good reviews in the press whilst  at the same time B&O speakers are ignored or dismissed as overpriced or not for the serious listener. It's a strange world!

Graham

It is (relatively) quite easy to design a good power amplifier which will measure and perform very well indeed. It is very difficult to design a speaker to do the same. Just fitting a power amplifier into a speaker cabinet isn't really the whole story, it achieves very little on it's own - what it does allow however is for the individual amplifiers response to be tailored to the individual drivers, for example each amplifier EQ can be adjusted to compensate for any deficiencies in each driver response resulting in a combination which gives a much better overall performance than the driver on it's own or even the driver driven with an external technically perfect power amp. These EQ adjustments are done at signal level (or even in the digital domain) before the power stage and so are relatively easy to achieve.

Most studio nearfield monitors are active designs - from a domestic hifi angle, it removes the ability to "fiddle, pontificate and upgrade" and hence isn't that popular among the believers.

Having said all that, and I agree with it, it is not true that all active speakers are going to be better than passive ones!! It is merely easier to avoid making awful ones unless you really don't understand what you are doing! B&O have made some excellent passive speakers but instead of the active amplifiers being used to tailor the sound to mask the deficiency of the drive units, the crossover is used to attempt to do much the same. However it has to be done forn an amplified signal and also without knowing the characteristics of the amplifier. B&O used to produce speakers for systems which seemed to sound particularly good with the system they were designed for. The Beovox 1200 and Beomaster 1200 spring to mind. Neither were very good in isolation but together they were very musical.

Peter wrote:

Having said all that, and I agree with it, it is not true that all active speakers are going to be better than passive ones!! It is merely easier to avoid making awful ones unless you really don't understand what you are doing!

😁Of course you're right, you can still make absolute stinkers!!!

However, making EQ adjustments at the signal level (or in the digital domain) allows much greater (and finer) control than attempting the same with power level crossovers etc.

Doing it well is where the skill/knowhow counts!!🙂

I agree - let's face it - the beolab 6000 is a superb example of what a speaker should not look like, A couple of car speakers in a drain pipe is a description I have heard used but despite this, the engineers at B&O have actually produced something that sounds not bad! A passive 6000 would in all probability be hilarious! Active technology allows engineers to tailor the amplifier to the drive unit but also to the enclosure which allows the designs seen at B&O. I am sure Geoff Martin sighs at times when he sees the latest design he has to work with and it is a testament to his skill that B&O speakers sound so good! Imagine the sound if he was given free rein with the design!

I have both active and passive speakers in my house,but have pros and cons.I have the beolab actives, where I don't want a dominating speaker,but decent sound.

A pair of active beolabs at say £3k will never compete with a good amp ,and passives at the same price.Like I said in the past I chose passive speakers with power amps,over lab 5s because they sounded better.

Saying that,Ihave just ordered the new linn akubariks,which sounded better than my old passive and amp setup,and cheaper too.Beolabs are great active as you can get decent sound from a small footprint,which looks good,beolabn3 are sensational for their size.

Peter wrote:

.... B&O used to produce speakers for systems which seemed to sound particularly good with the system they were designed for. The Beovox 1200 and Beomaster 1200 spring to mind. Neither were very good in isolation but together they were very musical.

That is a very good example of the fact that B&O for decades has understood that speakers and the amp are a pair - and not just two components brought together more or less by chance.

Consequently this has lead to the BeoLabs as we know them today.

Actually the BL14 and the15/16 are of the same kind - only the speakers cables are 'a bit longer' than when the amp and the speaker(s) are located in the same unit.

MM

Hi Graham,

Of course, it's easy to make a mess of anything. So, you can't simply say "active is better than passive" (or vice versa) because the statement doesn't contain enough information. I can say that "a bicycle can go faster than a car" if I know the extra information "if the car is a 2CV going up a "hill" in Switzerland and the bicycle is dropped out of a helicopter". 

In addition, as some others have mentioned, the advantage of an active loudspeaker design is not primarily due to the "one-amplifer-per-driver" topology.

The REAL advantage comes in the signal processing (which includes, but is not exclusive to "filtering" or "EQ" or "equalisation" or whatever else you want to call it) that you can apply to the loudspeaker independently to each driver.

To give just a few simple examples:

• You have a resonance in the woofer at a frequency that is above the crossover. You want to correct the problem in your filtering (because you can hear and/or measure it), but the problem does not exist in the midrange. So, you want to have a filter on the woofer alone - not the woofer and midrange and a passive crossover.
• You're using a driver that has a natural response that is "weird" around the crossover that you need to correct with a filter design that is not possible or not realistic to achieve with resistors, capacitors and inductors. As a very real example, I have a tweeter that, due to its electroacoustic design/construction has a high pass characteristic that (going downwards in frequency) starts off as a second-order highpass, and turns into a third-order highpass. In order to correct this so that it behaves well through the crossover region going down to my midrange, I need to do some tricky filtering (thank goodness for DSP!) on the tweeter itself. If this correction was not done, I would either have a weird frequency response, power response, directivity, or (most likely) all three would be a mess.
• You want to do time alignment of the drivers, but you're not allowed to change the physical shape of the loudspeaker. You can't fiddle with driver-independent delays through a passive filter. (I know, I know - you can do an allpass. But time alignment and phase -mucking are different things.)
• You want to do some dynamic processing on a driver without affecting the others. (for example, ABL or thermal protection of a single midrange, or thermal compression compensation of a woofer)
• You want to compensate for small differences in loudspeaker driver sensitivity on a production line by doing an automated measurement and a gain offset on a driver-by-driver, loudspeaker-by-loudspeaker basis to ensure that loudspeakers leaving the factory are better matched to the "golden sample"
• You want to do a linear phase crossover instead of a minimum phase one (for whatever reason you might have...)

An active loudspeaker design makes all of these examples MUCH easier (or perhaps "possible") to achieve.

All of that being said, if your electroacoustical behaviour of every component was "perfect" (whatever that means) and if loudspeakers behaved linearly (i.e. they gave you the same frequency response at all listening levels, and they didn't change their behaviours when they heat up, and so on and so on) AND if you did everything properly (meaning that your cabinets were the right size and shape) AND if your production tolerances of every component in the system was +/- 0%. Then MAYBE a passive design could work. ;-)

All of that THAT being said: It's certainly cheaper to stick a woofer, a tweeter, and a couple of electrical components in a box than to stick a woofer and a tweeter and a couple of amplifiers and a power supply and a DSP board and some ADC's and DAC's and whatever else you might need in a box. So a passive design does have THAT going for it... 

Hope this helps.

Cheers

-geoff