adapter for apple pro speakers?

Griffin used to sell the iFire adapter for the Apple Pro Speakers. It plugged into the Firewire port of the Apple computer and had a socket for the Apple Pro speakers.
Two slight problems:
1. Griffin no longer sell the iFire
2. The latest Macbook does not have a Firewire port

If you can obtain a used iFire adapter and an old iPod Firewire powerpack then you will still be able to use the Apple Pro speakers as the Firewire was just for power and there is an audio jack for plugging into the headphone socket on the Macbook (or iPod).
See http://users.tpg.com.au/aoaug/mac_video.html#ipod

The iFire is the amplifier for the system - the Apple Pro speakkers need an amplifier. You could try buying a cheap USB speaker set and use its amplifier to run the Apple Pro speakers. That does mean splicing wires.

I have been reading that people are trying to splice the wires on their Apple Pro Speakers to connect them to a regular headphone jack . I can tell you from experience that this will not work. The Griffin iFire and Griffin PowerWave work because they are external POWERED sound cards. Your iMac had a port that supported the speakers and fed them the necessary power to boost the sound, there are some towers out there with the special sound cards inside them as well. Without a powered sound card you get a very very low volume and unusable sound output.