Octave range changes the octave on the 2nd loop of an octave. No loop - no octave change. So if you want "Octave Range" to work - you need looping.

A bit of a pity.

Could be a nice feature.

Instead, it's less than half of one.

And another instance of misnomers in the UI.

An arpeggio is a finite number of notes. If you want the arpeggio to play a wider range of notes (including the original notes) - you have to play more than the original number of notes. The only way to play more than the original number of notes is to loop.

It may be useful to be able to define a finite number of loop cycles. This would allow for realizing I believe what you would prefer. Setting range and cycle count (cycle count being "science fiction" that doesn't exist now).

Using what is available today - if I want an arpeggio to play 2 cycles and "stop" - what I do is setup a motion sequence to lower the Part's level down to 0 after the 2nd loop.

This is one way. You could use a latched trigger and catch the arpeggio before the end of the 2nd loop. This requires timing.

Or gated and hold down until the end of the 2nd loop and let go.

I know what an arpeggio is, in various forms, on multiple synths, and much software.

The problem here is super simple.

Yamaha missed an opportunity.

The feature works as a basic "zero octave" arpeggio.

There is nothing that breaks or is otherwise compromised by making the octave range operate (correctly) without the looping turned on.

By its naming, octave range would tend to indicate it's a modification of the arpeggio. But it is not. It's a addendum to the operational mode of the looping arpeggio, instead.

Which it would also be if it operated (correctly) during non looped play of an arpeggio.

This is missed opportunity to provide greater flexibility, control and creativity without any form of compromise.

Is there a way, without turning on loop, to make an arp respond to changes to this octaves value in the way one might expect (that it plays 3 octaves up if that's requested, or 2, etc)?

Yes, there is. Set “Octave Shift” = +3, or +2, etc.

The Arp parameter “Octave Range” works exactly as intended.
The Arp parameter “Octave Shift” parameter allows you to trigger notes in one area of the Keyboard, and have it sound as much as ten Octaves higher or lower than the actual notes you used. No loop is necessary, it simply shifts where the result sounds...+/-10 Octaves.

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