Im looking for options that can work on phones as well technically with less (ohms), I've mistakenly already bought the Sennheiser hd 650 but after reading some reviews like these https://appuals.com/sennheiser-hd-650-open-back-professional-headphone-review/ its clear that it needs an amplifier and an iPhone wont be able to power it properly my questions are:

1: should I cancel my order
2: get a portable headphone amplifier?

Thanks!!!