Professional Chromatic TunersProfessional electronic tuning devices have the richest feature set and most detailed displays. They are tabletop or rack-mounted. These high-end professional devices are used by instrument technicians, luthiers and piano tuners, or incorporated into a rack for studio use. Many models are designed specifically for piano tuning. Professional tuners refer to these as "Electronic Tuning Devices" or ETDs. They can be programmed with alternate temperaments; they can be used to sense a note, then calculate desired frequencies for stretch tuning; they may even provide assistance for pitch raises.
Peterson AutoStrobe uses a strobe display using discs. Peterson offers a number of high end tuner models for other instruments as well as piano from $500 to $3200
Sanderson Accu Tuner IV for piano by Inventronics uses a series of LEDs in a circle for strobe tuning, and a text display with more information; $1500-1800.
Veritune 100 for piano uses a high-resolution LCD needle and strobe for its primary display; $1800. Veritune also offers a software version for handheld computers.