Journey allowed me to maintain current tempo (6,4)
I believe the answer is:
triple time
'tempo' is the definition.
(thesaurus)
'journey allowed me to maintain current' is the wordplay.
'journey' becomes 'trip' (trip is a kind of journey).
'allowed' becomes 'let' (I've seen this before).
'to maintain' is an insertion indicator.
'current' becomes 'i' (symbol for electric current).
'let'+'me'='letme'
'letme' going around 'i' is 'letime'.
'trip'+'letime'='TRIPLE TIME'
(Other definitions for triple time that I've seen before include "a very high rate of pay in unsocial hours?" , "What waltzers keep" .)