What's missing in lubuntu
 

In August of this year I'm going to build a dedicated linux audio computer. I have been using ubuntu studio on my cheapo dell optiplex to learn linux and to get used to different programs and see which ones I need.

Lubuntu seems to use less cpu than ubuntu studio for the same program. I don't want any other programs on my system part from ardour, jack and a few misc MP3 players. All audio. It says that ubuntu studio is a low latency program, does this mean that Lubuntu isn't low latency? It seems that Lubuntu is running the program easier but I'm nervous to go with it because I fear it may be missing certain components to keep it less needy of cpu power.
What are your thoughts on this.

When they speak of low-latency they mean that the kernel was compiled in a way that optimizes latencies for stuff like audiowork, where every fraction of a second of delay is counted. Lubuntu is aimed at the standard desktop and doesn't come with these optimizations, but since both are based on Ubuntu it shouldn't be a problem to run Lubuntu with the kernel of Ubuntu Studio.
Just give it a try, if it doesn't fit your needs you can always change.

A I understand it the real time kernel uses more processor cycles because it attempts to ensure that interrupts are polled for at measured, repeatable, intervals so that, for example, audio can be recorded faithfully and played back faithfully.
https://askubuntu.com/questions/1266...-realtime-ones
I did also think that the low latency kernels were being phased out of Ubuntu Studio as modern processors are so fast that they are capable of, for want of a better way of putting it, sampling rates higher than those of the audio encoding software making "real time" kernels largely redundant.