Laptop + external speakers: Will this arrangement work?

Factual Questions
1

I’ve got to give a PowerPoint presentation in a largish room. The presentation contains audio files.

Normally I give presentations in a normal-sized room, so I usually just plug a pair of external speakers into the headphone hole of my laptop and I never have a problem. The speakers, each about the size of a small cigar box, are self-powered (that is, they have a line cord that plugs into a standard wall outlet) and can fill the room with sound.

But I fear the 2-speaker arrangement will not be loud enough for the new largish room. I have some spare pairs of external speakers, and I was wondering if I could add an extra set to the mix. If I plugged a splitter (M-FF) into my laptop’s headphone hole, and plugged TWO pairs of the external speakers into the splitter, would it work safely? Would it deliver “twice” the sound?

I don’t want to risk ruining my computer, so I’m asking here before I try it or go out and buy anything.

Thanks all, in advance.

2

Gee, no replies??? Is this really such a tough question?

Let me give this a bump.

3

Okay, I will dive in.

If each pair has an amp, you should be fine. If you plug each pair into an outlet, each pair will take the low output from the headset ‘out’ and boost it.

4

…as long as you weren’t going to have to turn them up to 11 to make them audible. Splitting the original signal will reduce the maximum final volume achievable by each of the speaker sets, but as long as there is some amplification capacity to spare, it shouldn’t matter.

A better one-off solution might be to use a decent-sized portable stereo with a line in socket, as these typically have a bit more poke than a pair of computer speakers.

If this is more than a one-off - and particularly if it’s a professional context - you should probably invest in a proper amplifier and speaker system for the room.