If a piano is horrendously out of tune, a "pitch raise" is the most effective way to tune the piano. A JD Piano Service Pitch Raise is different from a pitch correction or pitch raise procedure often referred to by tuners because it involves two separate visits. The first visit is preparing the piano to be tuned. A significant pitch correction is made followed by a rough-tuning to re-establish the piano's overall pitch to A440. The piano will sound noticably better but it is not yet fine-tuned and some of the strings will tend to wander a little over the next few days. The follow up visit is scheduled 1 - 2 weeks later and involves fine-tuning the piano and stablizing the pitch.
Many tuners will attempt to tune a piano in one visit regardless of how far out of tune the piano is. Drawing on my 36 years of experience tuning pianos in homes and preparing both new and used pianos for display and sale in my family's retail store I've become very familiar with how pianos react to dramatic changes in pitch. If time, budget and situation allow, it is always more effective to give the piano time to adjust and settle in. So while it is possible to achieve satisfactory results in one visit, the stability of the tuning is questionable and more often than not will drift off in a very short period of time. It's a judgement call on my part as to whether or not your piano requires a pitch raise but in general if your piano has been neglected in some way such as not being tuned for several years or if it is typically subjected to wide fluctuations in humidity and temperature a pitch raise may be necessary.
PLEASE NOTE - Very old or severely neglected pianos may have structural issues rendering them unable to accept a pitch raise to A440 or worse yet, unable to be tuned at all. Again, this is a judgement call JD Piano Service will make at the time of the appointment. Options and recommendations will be fully discussed with the customer before proceeding.