I'd be surprised if your compact was truly geared only 2% taller than your hybrid triple. That would be unusual. But there's no way for us to know if you yourself don't know what the gearing is on either bike.

It's possible you can achieve the same low gear by swapping out the cassette, but depending on how big your largest cog is now, you may need a different rear derailleur to do that.

Which model Synapse? What year Trek? We might be able to look up the specs...