Describe the dramatic effect when Howard listens to the voices of his family while Willy tries to talk business in Death of a Salesman.

Several effects are achieved in this scene. Willy's
professional stature is brought light, Howard's happiness is juxtaposed to Willy's
misery, and Willy's self-control is demonstrated as being extremely
weak. 

Willy meets with Howard with the intentions of
getting a transfer. Howard does not give Willy a "proper audience" and instead tries to
avoid discussing Willy's problems. Though Howard may do this in order to postpone firing
Willy, he is pressed ultimately to terminate Willy. The audio player used in this scene
serves to raise the tension of the moment, making Willy ill-at-ease and disturbing
Willy's intentions. 

Howard wants to avoid Willy and focus
on a lighter subject. The fact that he can ignore Willy by choice indicates Willy's low
status in the business. 

Listening to the voice of his
child, Howard is shown in his happiness. This happy diversion from the rather serious
and desperate issue in Willy's mind creates a stark juxtaposition and articulates
Willy's difficulties. 

Given these challenges to his goal,
Willy loses control of himself and yells at Howard, his boss. The disruption of his
intentions made by the audio player can be seen to help lead to this
end.