Bookshelf Speakers electricity

[anirudh]

Hi guys,
I am a total idiot at this.
Please help me...
How are bookshelf speakers powered? I mean how do they get their 'electricity'. Is it from the amp?

Thanks

[Pano]

Yes, from the amp. It comes via the speaker cables.

There are things called "Powered Speakers" (more common in the pro world) that do plug into the wall. They have amps built into them. But the vast majority of home speakers get their power from the amplifier via the speaker cables. They have no other source.

[Cal Weldon]

There are also wireless speakers for those with an aversion to cables.

[anirudh]

Thanks for replying so quickly, Pano.
And Cal, wireless is not worth it, but thanks for the idea.
So won't bookshelf speakers work without an amp?
I need speakers for my gym and PC could you give me some advice for budget speakers.
Thanks,
ANi

[Pano]

I don't see how the speaker could work without an amp, do you? A bit like trying to drive your car uphill without an engine.

Since this is a DIY forum, you want to build your own speakers? What size and what budget? There are plenty of kits and plans around, if you know your goals. Let us know, and we can steer you.

[AlexQS]

Originally Posted by anirudh

Thanks for replying so quickly, Pano.
And Cal, wireless is not worth it, but thanks for the idea.
So won't bookshelf speakers work without an amp?
I need speakers for my gym and PC could you give me some advice for budget speakers.
Thanks,
ANi

I have a PC in my classroom at school. A small subwoofer plugs into the mains to run the amplifer. Two small seattlite speakers plug into that.

It gets its signal from the computer through the miniheadphone out of the soundcard.


It can work for me in a small classroom. About $49 - $150 depending on the quality you get.


The problem is that I think your gym is bigger than my classroom, and I barely have enough sound to fill my small classroom.


My laptop is connected to the aux input of my receiver at home. iTunes sounds really good with a real amp and fullsize speakers. Though my CD player sounds much better than my computer.

Don't expect any quality from computer speakers off the shelf. Your PC will sound best if you build some real speakers and get an appropriate amplifer for it.



Hope that helps,


AlexQS

[tvrgeek]

Let's back up a bit.

ALL speakers require an amp as they by definition are converting electricity into motion.

"Passive" speakers, as are most, use an external amplifier in the receiver, dock station etc. Some speakers, mostly like computer speakers are "self powered". That means the amplifier is built into the speaker. Besides the signal going to them, they need power. Often a wall wart for the computer junk. Some very fine ones are built this way. Meridian has some that cost more then your car. "Wireless" can be just as high quality as wired. It is all in the design.

Now, you want sound in your gym. That is a very specialized application and requires something more akin to "PA" speakers. A great many of then are also self powered. Don't mean to discourage you, but to have sound intelligible in a gym environment takes quite a bit of experience and skill. People make a living doing this.

[anirudh]

Ok, thanks Pano for clarifying that they WON'T work without an amp. But can it get power from the sub? And the sub presumably would plug into the wall. (Like AlexQS's reply)
I am a student in UK so, PartsExpress wouldn't be an avenue for me. I would need speakers, and an amp but from a UK dealer.
I am only 14 so...
And my gym is in an outhouse so echo is an issue. But I think for my gym, I should by OEM speakers from say Logitech. But for my office or my living room, I can whip up a setup most likely with an AV amp. My gym is not a GYMNASIUM, its an outhouse which has equipment and my Xbox.
So thanks everyone (Pano, tvrgeek and AlexQS)
Finally, after your advice, I think
For GYM: Standard Logitech
For Office: Better Logitech
For Living: Pioneer 5.1 Amp probably, and good bookshelf ones.
Thanks all,
Anirudh

[Pano]

You're welcome!

A lot of computer speakers do get their "power" from the sub. What that means is that the stereo amp and subwoofer amp are both built into the sub box - as that's a very convenient way to do it. Then there will be a wire out of the sub box to each speaker.

[chris661]

Someone here younger than me, that makes a change.

Where in the UK are you?

Also, I'd stay away from Logitech - while you couldn't make what they make for the money they make them for, you could make much better for a little more money.

How big is the gym?
I suspect you're going to need something pretty serious if you want to get loud sounds at a decent distance - a cheap Logitech system will not hack it (certainly not for the size of gym I'm thinking of - typical basketball pitch size)

Chris