If a piano has not been tuned in a long time – a year or more – it is often necessary to perform a pitch raise. All of the strings have to be retensioned which puts a great deal of stress on the frame of the piano. Once the strings have been brought to their proper tension levels, then the actual tuning can take place. In order to avoid having to perform a pitch raise, be sure to tune your piano, at the very least, once a year. Ideally you should have you piano tuned every 6 months.