From his vantage point as a widely regarded audio specialist and the Chairman and co-Founder of Audio Precision, the highly respected manufacturer of multichannel audio analyzing tools that recently celebrated 25 years in business, Bruce Hofer sees the encroachment of digital audio from a special perspective.
He’s passionate about analog, but believes this pristine path is under siege.
“To put it bluntly,” says Hofer, “analog audio is being reduced to smaller and smaller niches.”
But, wait. Digital audio specs are very good, and in live broadcast situations in particular, doesn’t digital connectivity reduce miles of audio cabling with a reduction in audio quality that most would consider marginal at best?
“There’s no doubt that digital processing has become more ubiquitous, and the performance levels that are obtained are quite adequate for most applications,” Hofer said. “Quite frankly, an awful lot is made of specs in the world of power amplifiers and A to D convertors, with the assumption that the bigger the numbers, the greater the quality.
“There does, however, come a point when the level of sufficiency for most people has been reached. For the most part, digital processing has reached that level. Most A to D and D to A converters have reached the level of performance that provides almost perfect audio in the minds of most human beings.”
Better technology has played a huge role in that, of course.
“We’ve even seen a great improvement in the area of microphones with the introduction of PDM microphones, which output a digital signal,” Hofer said. “The engineer doesn’t even have to worry about interfacing. Loudspeakers are without a doubt the weakest link in the audio chain. They require complex transducers and high power levels.
“Speakers are fairly large devices that introduce mechanical resonances. Designers are chipping away at the imperfections, but there is work to be done.”
That said, there is another side to all of this.
“Here’s the fly in the ointment,” Hofer said. “Digital is fine, but when you have to store the audio or transmit it through media that has limited bandwidth capability — a cell phone or handheld musical device, for example — you have to compress the audio, and that’s where the lions, tigers and dragons lie.
“We all remember the robotic sound of some of the early cell phones. That sound comes when you attempt to reproduce audio with inadequate bandwidth. An awful lot of consumer devices are still plagued with these problems. People are still working to get better sound quality out of limited bandwidth.”
Technology, however, has found a way to bypass those early performance blockers — to a point.
“Pro audio, obviously, doesn’t have these limitations,” Hofer said. “Record your work to a large hard disc, and no bits are lost. The problem comes when you want to mass produce your work. At that point, you have to run your audio through a digital conversion processor to get a lower number of bits.
“Without a high level of quality control, a significant drop in quality can be introduced at this point in the audio chain.”
So, where does this leave analog audio moving forward?
“I’m not saying that I’m scared, but as I said, audio is being reduced to smaller niches in the market place,” Hofer said. “There will always be a demand for microphones that output an analog signal. The days of the old desktop pre-amplifier — the beauty with analog volume and tone controls and a balance control to monitor the left and right images — they are over!
“More and more, we’re seeing the movement towards Class D amplification, where a switch shifts between plus and minus voltages.”
As for where his own company is headed as analog faces its unclear future, Hofer said remaining rigid is not an option.
“We’re nimble and we adapt,” Hofer said. “When we first started our company, we were catching the tail end of the LP, the beginning of the CD era. We had to learn about jitter, dithering and how to handle quantization of audio.
“In the future, we may develop an audio analyzer that’s 100-percent digital. The HDMI interface we offer has been exceedingly popular with consumer electronics manufacturers.
“I’m not so sure that HDMI isn’t about to displace SPDIF in terms of popularity. But, I hesitate to try and factor things out more than three to five years in the future. Someone’s going to come up with something revolutionary. Audio Precision will be there when they do.”