Are you talking about real gain numbers or your perception?
I’d you don’t have vents, everything ha sends your eardrum receive.
If you have vent and send the same stuff, you’ll get less at eardrum since sound escape.
When your change is ‘has vent’ and phonak adapts sent gain, keep in mind that thing you see on the screen is just some prediction.
If you get less than you need, that’s only a proof that prediction didn’t guess right for your earcanal and vent shape and size.
Without REM you can only go by feeling and increase gain until you hear similarly loud as before.
With REM you could exactly and fast hit the numbers needed. However, it also might be the case that receiver isn’t strong enough to send you enough.
Plus, bass is what gives loudness, the moment you open it, you can forget getting exactly the same.
This is background theory.
However if I understood correctly, you have the same molds and you just changed settings?
What phonak does is compensate for feedback, compensate for noise reduction and I forgot what else, but it effectively lowers the ability of receiver to send more, so if you’re already near the maximum, no go.
Gain isn’t what it sends really, it’s what he thinks it arrived to your eardrum based on acoustic parameters.
What’s sent you can see in other graphs, forgot the name, but under fine tuning, at the top somewhere, bunch of options.
Best confirmation what it exactly does would be with REM. But I hope you roughly got some idea.
I forgot what I searched, but it was about acoustic properties and how they generate programs and what are the challenges for example when you’re streaming and want to also hear your surrounding compared to streaming in quiet or just listening with has in quiet. But they definitely do a ton of calculations and predictions in order to compensate for changing in acoustics.
Yes, faster would be do REM, however, REM is done on barebone HA while this tricky adjustments are in heavily modded programs.
Probably it would be possible to use REM equipment to just measure real gain in various programs as well, but that’s not REM anymore, REM covers regular acoustics (so, in quiet, you earcanal shape, molds/cents/domes), so you couldn’t use REM targets for checking if you’re at the right position since they’re not meant for weird environments.
But still, we users have needs for weird environments, so maybe one day we’ll be able to do proper REM on all programs. Until then we rely on manufacturers guessing and own notes to tweak those other situations.
Hope this helps a bit