Yes, much quieter and cleaner. Tests on electric buses done by Altoona show a 5-10dB improvement for the interior and exterior noise levels. Newer designs are claiming as much as a 15dB improvement. Here is an example of the interior noise vs a diesel bus.
e-Buses are much quieter and this has benefits for the community and the riders. Here is an example of exterior noise vs a diesel bus, and here is an electric bus acceleration test.