There are no ribbon drivers in the IRS system. They’re planars.
They are aluminum mounted on a substrate. Not true ribbons but I believe Infinity called them ribbons, IIRC. Or EMIT and EMIMS, Electromagnetic Induction Tweeter/Midrange.
Who actually heard the Infinity IRS?
I've been looking at the very high value Arion speaker and it's called to mind a vintage speaker, the Infinity IRS. They are not the same speakers, but honestly I never actually got to even see an Infinity IRS in real life, let alone hear one.
I'm wondering if anyone has or even owns a quad (pair would be wrong) of them could talk about the sound quality and compare to anything today.