The TARDIS
Voice Integrator
conveys
the Time Lord's
telepathic
"Gift" of translation, allowing Gallifreyans and other humanoids to understand any language.
A switch beneath the console controls the translation circuit.
Right before materialization, a TARDIS will scan a planet's broadcast communications
to create a database for translations.
The Telepathic Circuits will
determine the local language
as soon as a TARDIS has materialized. It will then provide a very sophisticated and very accurate two-way translation for a TARDIS crew by telepathically altering the crew's brains so that they perceive the local language as being their own native language. It will appear to the natives that the TARDIS crew can speak
any
language. The effect is so seamless that inexperienced members of the TARDIS crew might not even notice that they can suddenly speak and understand alien languages.
Some even have difficulty telling the difference between thought and speech. If a user is aware of how the Voice Integrator alters their mind then they can, with significant concentration, bypass its effects and hear the language as it actually sounds (and see the text as it actually appears).
A fully functional Integrator will automatically alter the crew's names so that they sound normal to local aliens. It will also alter the crew's dialect to match whichever regional or cultural group they are currently speaking to at the moment.
Conversely, the translated speech of local aliens is often given an additional accent
in order to convey the alien's social class or educational level. The accuracy and appropriateness of these accents varies depending on the reliability of the TARDIS. The translations circuits can also be set to filter swear words out of conversation
(presumably by substituting less offensive words).
The Integrator can't translate extremely primitive languages without assistance from the Animal-Language Translation Circuits. New languages are stored in the Language Bank for future reference. The Voice Integrator can translate any vocal language because the speaker has a mind that can be read. The Integrator's setting can be increased
to translate written text if desired. But written text must already be stored
in the Data-Banks
in order to be translated, since the text has no mind that can be read by the Telepathic Circuits.
Languages whose written languages are very abbreviated or ideographic (such as Osiran Hieroglyphs) can cause the Integrator difficulties.
The only written languages not included in the Data-Banks are ones that have been described as "impossibly old."
In theory the Voice Integrator's effects only function for the crew of a TARDIS but
some TARDISes have been known to in selectively extend the gift to certain acquaintances of the crew. The telepathic circuits can
be combined with the Voice Integrator to
cause a person's words to come out backwards. If a TARDIS's Time Lord operator is undergoing a difficult regeneration
the Telepathic Circuits will be tied up trying assist the Time Lord and
the Voice Integrator will not function until the Time Lord has recovered.