Stacy Innerst, Post-Gazette Click illustration for larger image.

Ever wonder what it would be like to listen to some of your favorite old piano recordings in stereo -- maybe Art Tatum's 1955 mono recording of "Too Marvelous for Words" or Alfred Cortot's 1926 performance of Chopin's "Prelude No. 3 in G major" -- without the scratches or hissing sounds?

Now, that's entirely possible.

Zenph Studios, Inc., a tiny North Carolina software company, has created a 21st-century player piano by using computer technology that digitizes old recordings and feeds that information to a real piano in a real hall, allowing it to replicate the original performance down to the action on the pedals and the touch of each of the pianist's fingers on individual keys. That new performance is then recorded in stereo or surround sound, creating a rendition that is true to the original performance but one that is actually brand new.

There have been many previous attempts to refine old or poorly made recordings.

The standard approach has been to re-master them to filter out the noise and hiss -- but re-mastering can only accomplish so much. All the re-mastering in the world can't compensate for poor recording equipment or problems associated with clarity, acoustics and tuning.

"In terms of the music, what Zenph was able to do is precise," said Arnold Laubich, the co-author of "Art Tatum: A Guide to His Recorded Music."

Laubich was also one of a few people present recently at the Yamaha Studio in New York during a demonstration of the new technology. Laubich and others watched and listened as the Yamaha Disklavier Pro -- a computer-driven grand piano -- played the same notes with the same touch as Tatum did during the recording at a house party more than 50 years ago.

"It was a revelation for me to go to the Yamaha Studio and listen to the piano and watch the keys move and hear Art Tatum," Laubich said. "Zenph has done a very accurate job getting rid of the excess noise, pops and cracks, and you get to hear the full dynamic range of the piano and the beauty of Tatum's playing."

As a youth, Laubich attended seven Tatum concerts before the pianist's death in 1956. He said none of Tatum's recordings captured the breadth and dynamic range of the blind pianist.

"There were a lot of reasons for that," Laubich continued. "Most of his records were before the age of stereo. There was some fake stereo added to some of the recordings during the LP era, and they made it worse.

"His touch was soft and precise, but the dynamic range in old recordings was compressed."

Until the mid 1950s, recording technology was limited. For example, it was practically impossible to get the loudest and softest notes on the same recording.

One of the things that defined Tatum's aesthetic was his ability to balance notes in a chord.

"Every finger would have a different weight," said Laubich. "You can hear all that in the Disklavier."

John Q. Walker, Zenph's founder and president, said it took his people nearly three years to develop the software, which included building the engineering infrastructure.

One of the first things they had to do was build a dedicated recital hall with temperature and humidity control because pianos can be temperamental. Then, with the help of mathematics and a list of notes, they captured the sound waves on every single note.

Walker said they took into consideration the pedal movements -- how they moved up and down -- and the speed of the key strokes, as well as the harmonics. That information was then translated into MIDI or Musical Instrument Digital Interface language, a computer language created to allow electronic musical instruments and computers to communicate with one another.

But even after they mapped out the notes, there were hurdles to cross because the hardware wasn't good enough.

"Musicians spend their lives mastering the finest nuance of touch, and unless the instrument could reproduce that, it would be silly," said Walker. "Once we heard that Yamaha had built this exceptional piece of hardware, the software guys said, 'Let's go tackle the problem.' "

While the technology is in its infancy, Walker is optimistic it will eventually have as big an impact as digital technology had in the '80s.

"The central problem in all music research is to get the recording back to its original notes," said Walker. "This is a totally different way to think about how to produce a recording and what it means."

Walker said the technology will be marketed to record labels.

"They have the vaults of material of Tatum and other artists that don't get played on the radio or MP3 players because they were recorded in mono," said Walker. "These are great artists, but to record labels they are depreciating assets."