Small studio monitors are usually "active"; that is, self-powered.

They also are more likely to be a bit more accurate. This is not to say that small audio speakers are inaccurate, but monitors tend not to use "tricks" like a small upper bass boost to give the impression that they have more low end response than they do.

Everything that Elk said, plus:

1) All studio monitors are not self-powered, but more and more are these days.

2) Studio monitors generally cost less than "hi-fi speakers" for a given level of quality.

3) Not all studio monitors are particularly flat, even expensive ones that are highly regarded. I've seen measurements of many pro monitors and was distressed to see that most had an intentional dip in the "harshness" range between 2 and 4 KHz. So people report them sounding smooth and non-fatiguing. But they're not accurate, just flattering.

--Ethan

You might want to look at www.mixonline.com which is the electronic version of Mix magazine, a high end professional recording magazine that is a very interesting read. It provides information on the movers and shakers in the engineering/recording industry and updates new products like Stereohile does for audiophiles.

Some studio monitors can be nutty-priced just like audiophile products. Mastering engineers want to hear all the warts and problems in a recording to work to fix them (if they wish) prior to distribution. Most monitors can be brutally revealing.

The great recording engineer, Al Schmitt, joked that his wife was the audiophile and that she asked him why he mixed music on the old Yamaha NS 10's that were nortiously bright sounding. She could not stand to listen to them. His answer was that if he could get music to sound good on the NS-10s, it would sound good on anything.

How many times have we heard that many artists would take their tapes out and make sure it sounded decent on a car stereo. Yikes! Hardly a way most of us would think of a great way to know if a recording was mastered well. I think that now that idea is pretty much out the window...at least I hope so. Although there is one artist who was so in love with the sound of the ITunes "enhancements", that is how he mastered his last CD. That is awful, but it is his choice. Maybe that is his customer base.

I would think that most might not like the sound of studio monitors on a regular basis, but some might. I know a number of people who love the Event Monitors and they are very affordable. As with all speakers you need to audition before buying. If you find some monitors you like...go for it. Buy the equipment for what it does, not what it is. Great sound is beyond labels.

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1) what is the purpose of making them self powered for studio applications?

There are many advantages of active monitors for the typical project studio, besides a simpler hookup with less pieces to carry if you ever do remotes:

Active speakers are typically bi-amped, which often yields a cleaner sound with less distortion. And bi-amping offers more ways to optimize the crossover performance because it uses active rather than passive components. Also, the power amps will be well matched to the speakers, they won't have a fan, and the wires from amp to speaker are shorter which improves damping. But to me the overwhelming advantage, as implemented in the Mackies anyway, is that the woofer cone's motion can be included within the power amp's feedback loop to reduce distortion by a significant amount.

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2) So assuming a monitor and a book shelf of comparable quality and price range, can we say that monitors are more "true" in terms of sound reproduction...while hifi speakers are tuned to sound good to the ears?

Ideally, all speakers will be perfectly flat. At least that's what they should aim for IMO.

--Ethan

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3) Why is that in most of the studio pictures I see, they have monitors...why not have a full range Hifi speaker for doing the mix?

It depends on the studio and the types of projects it handles. Many large studios use what we think of as audiophile amps and speakers. Mastering studios in particular often use products with which we are familiar. For example, full range B&W speakers and Pass amps are common.

And what Ethan said.

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For example, full range B&W speakers and Pass amps are common.

Yes, and Bob Katz and others use Lipinski speakers.

--Ethan

Lirpa?