ATC buying advice

@mijostyn You are not looking at this right.

Active has zero to do with digital or "digitization". Active can be analog or digital crossovers and all class D amps. Active is simply an electronic crossover (analog or digital) operated at line level before amplifiers, amps hooked directly to drivers and no passive elements in between.

In the brand I work with, ATC, it is 100% analog: analog crossover, Class A/B MOSFET amps, no DSP digital anything inside. Same with older Genelec and many other active systems. You have to research this to know for sure.

Some of these active systems bundle DSP in to do "correction". What that correction is important because it could be "DSP room correction" or "DSP speaker correction".

Room correction attempts to fix an acoustical issue with some kind of EQ. This is controversial as you are now changing a speakers direct output based on the reflections in the room. What’s coming out of the speaker may not be wrong.

Speaker correction looks at correction of the crossover itself and how it affects speaker behavior and driver performance.

TRINNOV and DIRAC are room devices, addressing the acoustic problems in the room. This is still controversial, as fixing a "room" electrically is still something many experts argue about. The brand I work with (ATC) hates it as they say why fix direct sound when its reflections that are messed up? The only thing that may be right is the speaker itself but now you want to change that based on what the room is doing. Purists would say "Fix acoustical problems acoustically and electrical problems electrically".

Whether amps are digital (Class D) or not is not part of the DSP room correction. You could use DSP room correction in front of analog speakers, like your preamp or receiver having DIRAC but used with pure analog speakers. Or using a Trinnov in front of a ATC analog speaker. In the case of DEQX, it is a replacement for crossovers and speaker correction, a very different "problem" compared to room correction.

Brad

@lonemountain 

Hi Brad,

DEQX does both speaker and room correction, separately. I greatly prefer the DEQX system which is more like the TacT system I am use to. I do not yet know how much manual tweaking I will have to do. As far as room correction is concerned, there remain issues that have to be handled acoustically. The room has to be in tolerance or you will just clip filters. The types of loudspeaker being used are also important. Certain speaker designs have far less room interaction. When it comes down to brass tacks there are two major types of errors, errors in amplitude and errors in time. These are easy to correct for, to a point. You cannot correct for echoes. There are problems that have no analog solution. Other then by shifting position there is no analog way to put a delay on a speaker, and the dimensions of the room and other practicalities put severe limitations on how far you can move anything. 

Yes, you can do an analog active loudspeaker. The only good reason to do that is you do not have the engineering to do it digitally. Digital signal processing including crossovers is, in every way, superior to analog signal processing. Analog signal processing is about as useful as tits on a bull.  The only exception is in the mind of the audiophile. Audiophiles are as change resistant as cyclists. It took a decade for the cycling community to accept synchro shifting. 

As for the type of amplifier that again depends on the loudspeaker, even the independent drivers can dictate amplifier choice. 

Yes, you can do an analog active loudspeaker.  The only good reason to do that is you do not have the engineering to do it digitally.

@mijostyn That’s just simply not true — there are lots of benefits to an analog active speaker, but I’m sure @lonemountain could do a much better job than me describing what they are.

The idea that it takes superior engineering to do digital crossovers or eq is hillarious.  Anyone can do that.  The only reason to do digital is because you don't have the engineering to do it analog, obviously.  

@soix 

There may be advantages over regular methods in some designs but they pale in comparison to what can be done digitally. You have to remember the designer has no idea what environment the speaker is going to be placed in and the room is 50% of the equation, some would say more. Analog can not deal with this. Eventually systems could be digital all the way to the speaker enclosure. With good cable you can easily run a 300 foot AES-EBU line without any loss. 

@jon_5912 

You have to be kidding me. Analog electrical engineering has been around for eons. I built my first amp when I was 13 years old. Digital signal processing is about 25 years old. It is an entirely different branch of electrical engineering and requires specific training. Programming the crossovers is easy, but that is not designing the circuitry. 

The only reason to do anything in analog is to hand an analog signal to the amplifier so you can listen with your analog ears. Unless you have a large record collection everything should remain digital up to the amps. Not only will such a system easily outperform any analog set up but you can also tune such a system to sound any way you want without any added artifacts. I digitize my phono stage and do the final RIAA correction by computer.  I also use tube amplifiers to drive ESLs.