# Block-level merge synth defaults

``

    with_merged_synth_defaults

Specify synth arg values to be used by any following call to play within the specified `do`/`end` block. Merges the specified values with any previous synth defaults, rather than replacing them. After the `do`/`end` block has completed, previous defaults (if any) are restored.

Introduced in v2.0

## Examples

# Example 1
``
    with_merged_synth_defaults amp: 0.5, pan: 1 do
      play 50
    end
| ``
    # => plays note 50 with amp 0.5 and pan 1
# Example 2
``
    play 50
    with_merged_synth_defaults amp: 0.5 do
      play 50

      with_merged_synth_defaults pan: -1 do
        with_merged_synth_defaults amp: 0.7 do
          play 50
        end
      end
      play 50
    end
| ``
    #=> plays note 50

    #=> plays note 50 with amp 0.5

    #=> plays note 50 with amp 0.7 and pan -1

    #=> plays note 50 with amp 0.5