2 simplest ways around this:

1) Getting a soundcard for your PC with optical input, speakers will then be connected to the card via analog connection. The DAC on the soundcard will handle the audio info to your speakers. Downside is, if you are playing on a TV, this basically means you need a PC next to your PS3 along with it being turned on whenever you use your PS3.

2) Get a receiver. This is the simplest way but decent receivers costs upwards of RM2k+. Which then at this point you'll realize how subpar the R501 are and want to upgarde your speakers, even more money will be burnt.

There are "cheap" HTIB, the ones you see on those Carrefour/Courts Mammoth catalogs. The ones that cost RM899 or some stupid promo being RM699 + free whatever they wanna give.
Those HTIB are a laughable stock of sound quality, ridiculous they even charge that much in the first place.

For a soundcard, you can probably find a Creative Titanium (non HD) second hand in garage sales or if you're not urgent, wait for the release of the Creative Soundblaster Z series in Malaysia (supposedly this month).

No idea how much it'll sell in Malaysia.

It's $100 for the basic Z in the US. So expect it to sell for at least RM350 here.

The Z has a better DAC than both the Titanium and the Xonar DX.

SBZ - Cirrus Logic CS4398 + a dedicated MAX97220A heapdhone amp.
Xonar DX - CMI-8788, no headphone amp, no optical in as well.
Titanium - Cirrus Logic CS4382, no headphone amp, has optical in.

The CS4398 on the Z is clearly a step up on the CS4382, the improvements are mainly on cleaning up the low and mid range. Other than that, the Z also uses nichicon gold capacitors (although some batches sold now are using cheaper Fujicon caps), power delivery is much cleaner than on the Titanium.

As for the DX? It's still a fairly decent card. Especially you can get it for lower than RM250 now a days, but since you need optical in... it's not a viable option.

I can go on more, but this isn't a soundcard thread so don't wanna go off-topic too much.