Hello
Do you have any interest in any other field of engineering?
First reason why i asked is because you said you were interested in engineering courses, and maybe aerospace engineering.
Second reason is: from the course contents of aerospace engineering, it is a combination of Mechanical/aeronautical and Electrical engineering stuffs. It is more specialised than purely diploma in electrical engineering or dip in mechanical engineering.
Most important reason is because i don't recall SP having aerospace engineering(maybe now have), from my memory SP have either Aeronautical Engineering or Aerospace Electronics.
The two courses is quite different, can go SP website and look at the course content of the two courses.
Maybe you can take note of these when selecting your course of study.
Also maybe you can go read up on other engineering courses so to see if there is any other field of engineering that you have more interest in, and to make a more informed decision.
Your decision now is quite important, will affect your uni course selection and what you study in uni.
I also noticed you frequent the Home theatre & Audiophile forums and you have interests in speakers/subwoofers/audio stuffs.
I share the same interest as you(in audio/sound systems/amplifiers) thats why i chose diploma electrical engineering, and i specialised in aerospace electronics at that time.
Just another option (not saying you must) is to study electrical engineering if you have a lot a lot of interest in the audio electronics. I am sure you heard of crossovers, power supply, transistor amplifier(class a ab d g h etc), tube amplifiers, all these are just applications of electrical engineering. But at diploma level don't really go into the details of these.