Strong beat via bass (5)
I believe the answer is:
throb
'strong beat' is the definition.
'throb' can be an answer for 'beat' (throb is a kind of beat). I am unsure of the 'strong' bit.
'via bass' is the wordplay.
'via' becomes 'thro' (I can't explain this - if you can you should give a lot more credence to this answer).
'bass' becomes 'b' (abbreviation in music).
'thro'+'b'='THROB'
Can you help me to learn more?
(Other definitions for throb that I've seen before include "Sound of engines" , "beat repeatedly" , "One's heart may do it" , "Strong rhythmic beat" , "Pulsate strongly" .)