Well... I can't answer for Arvon but...... yes you have to program everything in (Bass,Drums,etc.), or download it from the internet. Programming it in can be hard, but it can also be quite easy... it all depends on whether or not you know what you want it to sound like and if you know how to get there. For example: suppose you wanted to program in a Soft Rock beat for one of your songs.... you would probably use step-by-step recording to program it in... this normally starts off with you telling the keyboard what to play and then telling it how long to play it (I'm almost sure about that anyway) then you proceed to the next "step" Example: you tell the keyboard to play a bass drum and a hi-hat cymbal on beat one, then you go to beat two and tell it to play just the hi-hat, beat three has the hi-hat and a snare drum, and beat four just has the hi-hat... then you can probably tell the keyboard to loop this thing over and over again, then eventually you would add fill-ins and variations for choruses and other stuff. If you didn't know what a basic drum pattern is like though, you would end up with something that sounds like a new drummer just banging around. That's just my understanding though, I could be totally wrong, the only keyboard I've ever programmed stuff in on is a fairly cheap thing that is probably a whole lot weaker than the Triton's sequencer.
Now on the other hand with an arranger keyboard (such as the Roland G-1000, EM-2000 and most likely the Technics keyboard your friend is getting), you don't have to program hardly anything in..... Arranger's use "styles" which are preprogrammed drum, bass, rhythm guitar, etc. accompaniment parts. Most of the time you tell it what chord progression to follow and then start it up and trigger fill-ins, variations, endings, etc. by footpedals or buttons on the keyboard. This allows you to find the style of a song you want to do (Rock, Swing, Soft Rock, etc.) in the style bank of the arranger keyboard and then just hit start and the bass, drums and other parts will automatically follow the chords you play (I think) You can still program in things like on other keyboards, but you also have the flexibility of live performance. For more info on arranger keyboards and to find out if you can load the styles from your friends keyboard into whatever you decide to get, go to the "General Arranger Keyboard Forum" on this site and post there. Hope this helps you.
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