Unless otherwise provided in the will, a general pecuniary legatee shall not be entitled to interest on his or her legacy for the period of one year from and after the death of the testator. After the one year period the executor or administrator with the will annexed, unless otherwise provided by the testator, shall not be chargeable for more interest on any pecuniary legacy than the entire net income actually earned by the legacy if and when left in the investment as made by the testator, or actually invested in notes secured by mortgage upon real estate situated in this state, or in the bonds of any city or town in this state, or deposited in any savings bank in this state, or in the participation account of any trust company in this state, or invested in any other manner specially ordered by the probate court. But if otherwise invested, the legacy shall bear interest at the rate of six percent (6%) per annum or such larger rate as the same may have earned; provided, however, that nothing herein contained shall authorize executors or administrators to make investments other than trustees are allowed to make, unless specially authorized by the will to do so.