Thor SP-100 mini speaker system

Review date: 27 September 1999.
Last modified 03-Dec-2011.


A lot of PCs now have sound cards in them with signal specifications that wouldn't look out of place in a pro audio studio. But these whiz-bang audio sources are often connected to seriously unexciting speakers. The little three inch (or smaller...) drivers in most PC speakers can, when driven by the two watt amplifier on most sound cards or by their own built-in amps, deliver a decent amount of noise, but they've got lousy bass, and are often crammed into awful little plastic boxes that strangle what sound quality they might otherwise be able to manage.

You can get around the bass problem by using a speaker system with a subwoofer (like one of these, for instance) or just hooking the PC up to your stereo. But the better the speaker system, the bigger it is, and this can cause problems. What if you don't have the space? What if you're always moving the computer around, and don't want three extra boxes to schlep? And it wouldn't hurt to save a few dollars, either!

SP-100 speaker system

Here's the epitome of the small-and-cheap speaker system. The somewhat oddly named Thor Speaker SP-100 system is so small that you actually mount it in the computer - it screws into any vacant 5.25" drive bay! It's got its own built-in amplifier and a pair of 1" drivers, and it'll work in any PC with a sound card and a spare bay. The retail price is $49 (Australian dollars).

Setting up

Installing the SP-100 (I refuse to call this tiny thing "Thor") is simple enough. You screw it into any drive bay you like (screws are included), and you plug its passthrough power cable into any Molex connector from the power supply. The SP-100 runs from the 5V line, so it shouldn't overstress anybody's power supply - the 12V line is usually the one that runs closer to its limits.

Next, you screw an (included) blank expansion slot cover with a hole in it into any rear panel slot that's not in use, and feed the audio cable from the SP-100 through the hole, and around to the speaker output of your sound card. This is a little funny looking, but you try thinking of a better way to hook up internal speakers.

The SP-100 is made to take speaker level input from the sound card, and its volume control gives you enough flexibility that you won't need to fiddle too much with your sound card volume settings. There's also a headphone jack, and a little green power light.

Once the SP-100's in place, you can pivot the speakers left and right a little to aim the sound at where you're sitting. The pivot action is smooth, and indeed the whole unit feels nice and solid, considering the price.


Removing one screw at the pivot point lets you lift the speaker unit out of the mounting frame, and reveals the simple circuit board and two teeny speaker drivers.

Inside view

The packaging claims that the SP-100 has a ten watt amplifier, which is, to use a technical term, a bunch of hooey. Each driver is rated at only 0.2W, which is plenty for a one inch transducer, and the amplifier is a simple single chip job that couldn't output ten watts if its life depended on it. I love these PMPO numbers.

The tiny drivers have commensurately tiny magnets, and their magnetic field is negligible anywhere outside the SP-100 casing, except for right in front of the drivers, where there's a noticeable field - but it drops off very quickly with distance. If you're in the habit of rubbing floppy disks on the front of your computer, this could be a problem for you; otherwise, the SP-100 should cause no data corruption difficulties.

How's it sound?

I was expecting pretty darn underwhelming sound from the SP-100. There's only so much you can do with one inch transducers. There are telephones with bigger drivers, for Pete's sake.

Big Disco Bass is, indubitably, not going to happen, and with the drivers less than four inches apart you also can't expect much in the way of stereo imaging.

I was pleasantly surprised, though. The Thor actually sounds not bad at all, for what it is. Stereo is barely discernible if you push your head up against the front panel of the computer, and there is indeed no bass to speak of, but I have definitely heard tinnier sound from drivers this small. You can even get a reasonable volume level out of them, although it won't compete with regular unamplified desktop speakers driven by the standard two-or-so-watt amplifier on most sound cards.

I think the reason the Thor sounds passable is that it's got a comparatively large airspace behind the drivers, rather than penning them up in the plastic matchboxes that usually house such teeny units. Speaker aficionadoes know that a good box can make bargain basement drivers sound rather nice; nothing's going to turn a one inch driver into a hi-fi component, but a bit of enclosure volume helps a great deal.

The Thor is still not a startling, sounds-bigger-than-it-is audio experience; it's more in line with the sound quality from a not-too-expensive clock radio. But I could live with this, for game effects and light classical background music and, of course, simple system sounds. Clicks, dings and beeps, or the light and peaceful Vivaldi of your choice, come over just fine. Rumbles, explosions, Barry White and Wagner are rather less impressive than they should be.

Worth buying?

If you've got a cutting edge sound card, for Pete's sake get some good speakers, or headphones, to go with it. Otherwise, you might as well have bought the cheapest card you could find.

But if you're out of desk space, or if you cart your computer around a lot, the SP-100 could be just what you're looking for. It's got enough volume for game playing anywhere but a really raucous LAN party, it doesn't sound horribly bad, it isn't all that expensive, and it makes it impossible for you to accidentally leave your speakers at home. And since the SP-100 hooks up at the back as normal, you can always unplug it and plug in bigger speakers whenever they're available.

If you don't have a spare 5.25" drive bay, of course, the SP-100's not much good to you. But most people do have at least one such bay lying fallow.

The SP-100 is well made, sounds all right, and isn't very expensive. Hi-fi it ain't, but it makes up for it in convenience.

Buy stuff!

Aus PC Market don't sell the Thor speakers any more. They moved on to some $AU38.50-delivered "Laser" internal speakers that were the same thing, but those are out of stock as well now.

They do, however, have the Creative Travelsound Notebook 500, another one-piece two-driver setup that's made to clip onto the top of a laptop screen, but could be put anywhere you like - including on top of any kind of desktop monitor, giving the same zero-footprint advantage as the Thor.

USB or battery power, only $AU33 delivered - I think we have a winner. Australians who'd like to order a set can click here to do so.


How can a couple of 0.2 watt drivers constitute a "ten watt" speaker system?

Welcome to the wonderful world of PMPO. PMPO, which stands for Peak Music Power Output, is basically a lie. In theory, it’s the power a system can output for a split-second when fed a really high signal level, but since there’s no standard way of working this out (how high? How long?) different manufacturers’ PMPO numbers aren’t even comparable. Nonetheless, the "more watts is better" attitude is a popular one among consumers and manufacturers, and so laughably high numbers like this persist. Nobody's going to pay for a "half watt speaker system".

Give Dan some money!
(and no-one gets hurt)