Most modern tanks have moved to a dual, or triple drain configuration; referred to as Herbie, and BeanAnimal respectively!
The move to multiple drains is both for noise mitigation, and flood protection via drain redundancy! (These configurations run near dead-silent, with one of the drains at a metered full siphon, and the other left wide open as a failsafe!)
You can typically convert tanks which have a single drain, and single return hole drilled to a dual drain (Herbie) tank, with the return plumbed over the rim, if so desired!