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Why passive speaker better than active speaker?
I use chord, MC2 audio and bryston power amp to drive ADAM passive speaker,the performance of passive speaker better than internal "ICE power" class D amp.What is the reason of a company using active speaker instead of passive speaker?
The performance of active speaker is very weak even active speaker has a internal electronics crossover and build in power amp.
Follow Ups:
Bill in public address there are phase and amplitude problems because drive units are being fudged for maximum SPLs, DSP chips can help but not fully resolve the problems. The same applies to the ubiquitous 3" dome, DSP would help but a decent modern cone drive unit works far better.
However in purist High fidelity or studio monitoring applications, far better performing drive units can and should be chosen. They will require no fudging just a crossover that conforms to classic theory and a crossover is an analogue function.These are issues we don't think are fully understood by many manufacturers, otherwise loudspeakers would be much better than they are.
FWIW I'got Tannoy LittleReds which I originally used passive with a MC2 MC450.
Very nice speakers indeed and the amp not bad either.
But since I converted them to full active operation, using a BSS 360 xover and an additional MC2 T500 for the treble they are in a completely different league. Easily equal to the best active main monitors (PMC, ATC etc) except in bass extension!Not the first time I've converted speakers to active (or been present when somebody else done it) and all other things being equal, active operation always proved to be much more accurate. Especially in the bass the improvement is quite dramatic: There is a lot more detail reaching the driver which in passive operation gets 'smeared' by the series inductor.
The bass becomes clearer, faster and much better controlled. You also get 3dB more power reaching the driver which usually gets converted into electro-magnetic energy and heat by that inductor. Another advantage is that the inductor in passive speakers can, by means of the constantly changing magnetic field it produces, negatively influence the fields of the drivers motormagnets.All in all, if you compare the same drivers using the same amps, active operation wins any listening test every time. This is all well documented and researched. Just try googling.
Of course if you compare passive ADAMS driven by the quality of amps you mention to a generic little active job driven by a toy amp the result is a foregone conclusion...
There's no doubt you can achieve better performance with a mega bucks amplifier powering the passive version than with the active version... After all, the passive version is also well designed. But if you would put the same amount of money in a cable/amp/passive speaker set than you would put in the active version, I doubt you could achieve the same performance.
and like them both. In my case, passives are JBL 4425s and UREI 809s and 813s. I drive them with tube electronics. These are all horn-based speakers, BTW. These allow me to 'hear back' into the earlier stages of gear that I use or may be modding or updating. With them, I can hear the difference in sonic characteristics. I also use them for mixing down my little 8-track Cubase system as they were intended.I also have a set of older JBL 6604 self-powered speakers that I use when I'm out traveling. They're light, sound quite good and provide my clients a fast playback of recordings done on site. They're also nice in the sound room (my kitchen) when I need to do some fast editing/mixdown in a nearfield setup. The big speakers are all far-field brutes.
Hope that helps. BTW, there's no such thing as a 'best' speaker. There are plenty of options based on your needs.
Cheers,
In theory Active speakers are better because each drive unit has its own amplifier and is therefore driven over a limited bandwidthwith consequently reducing Intermodulation distortion. You've also removed the resistive losses of a passive crossover components and gained better control of the drive units which means even less distortion.Active crossovers operate into a resistive load and therefore conform to classic theory which means seamless integration, better clarity and accurate phase behaviour so a better stereo image.
In practice is it possible to mimic the action of an Active crossover and get very close with a passive design but it rarely happens because most speaker designers aren't electronic engineers and don't understand the implications of what they are doing. Many still use resonances in crossovers to correct drive unit anomolies and so on. Therefore it may well be possible to convert passive speakers to active and gain a massive improvement. Equally there are some pretty rotten actives around.
An enormous benefit can be had by going active if drive units with a very broad bandwidth are selected (to get really good phase behaviour) with a gentle roll off and steeper filters are chosen than is practical with passive designs. Much of the harsness that two way speakers have is caused by the tweeter being audible below the crossover and intermodding like hell. Using 4th order filters reduces this dramatically.
Definition is improved by removal of the passive components too, bass tightens and mid is much clearer.
Another advantage is that high voltage, low current and ultra low distortion, dedicated power amps can be designed that are far better and cheaper than the great monsters beloved of Hi Fi Journalists. These are necessary because speaker designers can't do a proper crossover and impedances are often far too low. 2-3 ohms is common where an 8 Ohm drive unit has a DCR of 5.4 ohms and is much kinder to its Amp.
Therefore Active speakers have the potential to be substantially better than passives and they must be the future. The problem at the moment is that there are good and lousy examples of both and it makes it difficult to tell.
The typical low end active speaker is no more than a speaker with amps and a crossover in the same box. For the most part the only advantage it has is an active crossover that may be better optimized for it than an outboard or passive, and here well integrated high quality separates for the most part will work just as well, if not better. Where things are markedly different is in the upper end, where an on-board DSP perfectly optimized to the speaker offers both frequency response and phase response characteristics that simply cannot be duplicated with separates. This level of technology is rapidly moving down the price point spectrum, and within the foreseeable future will dominate the market.
Bill you need to have speakers that work, you simply can't compensate for drive unit deficiences with a DSP any more than you can with an analogue electronic crossover. To talk about high end or low end is misleading, correct engineering is what counts.For instance, a typical High End 3" dome rolls out at 12dB at best and typically 24dB per Octave below 500Hz, resonance is usally around 400 Hz and this is before a crossover is applied. Please explain how a DSP can resolve this problem and produce seamless phase and amplitude integration of the bass drive (or the tweeter for that matter because they are just as bad at the top)with adjoining drive units.
We've found that drive unit anomolies cannot be corrected and that crossovers must conform to classic theory, hence my stating in my previous posting that only broad bandwidth ones will work properly.
While integrating DSPs into the design process hasn't yet become popular in the hi-fi end of the spectrum it's de riguer in pro-sound, where it's been a staple commodity since EAW introduced the KF850. True, a DSP can't correct basic design flaws. But for better or worse speakers that rely on analog hardware rather than digital software will eventually suffer the same fate as analog media.
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