Hi there! Thanks for posting to community
Most home-listening devices get 128kbps - whether the account is free or paid.
For listeners accessing Pandora from a computer, Ad-supported Pandora is 64kbps AAC+, while Pandora Plus and Pandora Premium subscribers have the option of 192kbps.
On Android and iOS devices, ad-supported listeners and Pandora Plus subscribers get anywhere from 24kbps to 64kbps in mono or stereo, depending on the phone, carrier, connection type and - in some cases - the user's settings. Only Pandora Premium subscribers can receive 192kbps on their iOS and Android devices.
Hope this helps.