Anyone know where all 21 speakers are located in the rx500?
i can visibly only find 12

 

Many of the speakers are 2-in-1
Here's a video of the speaker locations in the 22 NX Mark Levinson system, timestamp 4:35. Maybe it can help you.

 

https://lexus.jp/models/rx/pdf/rx_catalog.pdf

Page 63 of 106 of this PDF shows the location of the 21 speakers in the Mark Levinson audio system.
Unity speakers are 2-in-1 speakers.
The same page also shows the location of the 12 speakers in the standard audio system.

I'm sure there's an English version somewhere, but I can't find it.

 

Here’s a screen shot of the relevant page.

 

Mark Levinson’s web site was finally updated for the 2023 RX: https://us.marklevinson.com/in-lexus.html#rx-2023

 

They have the subwoofer on the wrong side

 

Nice catch!