The December 2022 issue of IEEE Spectrum is here!

Close bar

The Consumer Electronics Hall of Fame: Wadia Digital 170iTransport

After a long struggle, audiophiles finally managed to persuade the famously “closed” Apple to open up its iPods

4 min read
photo of the Wadia 170iTransport
Bit Player: The Wadia 170iTransport was the first device capable of extracting the electronic data from an Apple iPod so that the digital music files could be played through a superior digital-to-analog converter.
Photo: Wadia

The Wadia Digital 170iTransport, introduced in 2008, occupied one of the narrowest niches in electronics industry history: All it did was extract the bits from Apple music players such as iPods, enabling the data to be converted to music by higher-quality electronics than what was installed inside the players. But that was a bigger deal than you might think, because it helped demonstrate that the digitization of music, begun some 25 years earlier, wasn’t all just a terrible mistake. 

From a professional standpoint, digital music sounds like dreck much of the time. The reason is that there are a lot of things you can do with music in the digital domain, and most of them are bad. Between listeners and the companies that make playback equipment, those things are done quite often. There is nothing nefarious about this. Achieving superior sonic fidelity has always been costly, and there has never been a time in the history of recorded music when the best sound quality was easily affordable. Of course, that was also true of Apple iPods.

When Apple introduced the iPod in 2001, there were two models: one with 5 gigabytes of memory, the other with 10 GB. Part of the attraction was that you could fit “1,000 songs in your pocket,” as Apple’s advertising trumpeted. Prior to the iPod, nothing existed that could store anywhere near that many songs.

Five GB—or 10 for that matter—is both a lot and not very much. If you want to squeeze 1,000 songs into 10 GB of memory, you need to make the digitized music files smaller. There are many different ways to do this, but the most common one at the time was MPEG-3 encoding. MP3 encoders compress files: They take the digital data representing a song and eliminate some of it. Some of this excised data corresponds to frequency bands where human hearing is weak or absent. In addition, some—but not all—of the missing data can be reconstituted, and that is why MP3 is described as “lossy.” The upshot is that the use of a lossy encoding scheme diminishes audio quality in various ways, especially if you are young and your hearing is good. Most of the impairments are subtle, but a very important characteristic that suffers is dynamic range, which is the difference in amplitude between the loudest and faintest sounds that can be stored and re-created.

Apple, too, made compromises on the hardware side. In designing the iPod, Apple chose to use an inexpensive and low-quality digital-to-analog converter (DAC). The company had to hit a consumer price point, most people were going to be listening to lossy MP3s anyway, and they’d also be listening on relatively low-quality headphones. So using a cheap DAC was a rational design decision.

The cost of memory is driven down every year, however, and as the years went by, Apple released players with more and more capacity (as of this writing, the last iPods still in production max out at 128 GB). The additional memory encouraged people who cared the most about sound fidelity to switch to other encoding-decoding schemes, such as Apple Lossless—which also compresses files, but much less so than the most common version of MP3. Lossless encoder-decoders do not discard audio information, so they do not, in theory, have any effect on audio quality.

As they began accumulating iPods, audiophiles wanted to use them like any other stereo component, such as a CD player. In particular, some of them had paid hundreds or thousands of dollars for a fancy DAC and naturally wondered why Apple wouldn’t let them play the lossless files stored on their iPods through their costly electronics.

A stalemate ensued for years. Apple refused to upgrade to a better DAC, but neither would the company enable anyone to gain direct access to the digital files. Audiophiles kept on badgering the company about it, however, and in 2005 Apple relented and announced it would allow its DAC to be circumvented—but only by equipment manufacturers who would abide by Apple’s strict requirements and oversight.

The first to do it was Wadia Digital. Wadia was a curious volunteer for the job. What the company was known for was fairly high-end components that had list prices in the four figures.

Introduced in 2008, the Wadia 170iTransport looked just like a standard docking station, but that’s not what it was. Once an iPod was plugged in, all it would do was fetch the requested digital stream, bypass the iPod DAC on the way out, and transport the stream to some other system equipped with superior sound reproduction capabilities (which is why it was called a “transport”). That was enough to make the $379 system a minor hit, but in addition to supporting the use of iPods for high-quality audio, Wadia also incorporated in the 170i outputs for similarly high-quality playback of digitized films.

“I think the 170i showed people that digital music could work,” said Chuck Hinton, vice president of technical services at McIntosh Laboratory and of Wadia (both of them now owned by McIntosh Group, in New York City).

Hinton said he’d seen the 170i at a trade show when it was first introduced and was knocked out by the sound quality. “People demonized MP3s, just as they had demonized CDs when they first came out. The problem was just cheap DACs. Wadia showed that digital music could sound good, that MP3s weren’t complete garbage, as was mistakenly thought. The hardware was partly to blame.”

By the way, and perhaps not coincidentally, Wadia was also known for designing exquisite DACs, and it created a separate converter box to complement the 170i.

The Conversation (0)

John Bardeen’s Terrific Transistorized Music Box

This simple gadget showed off the magic of the first transistor

5 min read
 A small electronic gadget encased in clear plastic has a speaker and some buttons.

This music box demonstrated the portability and responsiveness of the point-contact transistor.

The Spurlock Museum/University of Illinois at Urbana-Champaign

On 16 December 1947, after months of work and refinement, the Bell Labs physicists John Bardeen and Walter Brattain completed their critical experiment proving the effectiveness of the point-contact transistor. Six months later, Bell Labs gave a demonstration to officials from the U.S. military, who chose not to classify the technology because of its potentially broad applications. The following week, news of the transistor was released to the press. The New York Herald Tribune predicted that it would cause a revolution in the electronics industry. It did.

Keep Reading ↓Show less

Liquid Metal Stretchy Circuits, Built With Sound

Encase metallic droplets in plastic for elastic electronics

2 min read
Dark photograph of gloved hands holding an item that has the letters DMDL, with glowing yellow rectangles in an assortment of spots on the letters.

Liquid metal particles sheathed in polymers connect microLEDs to make an ultra-stretchable display.

Korea Advanced Institute of Science and Technology

A team in Korea has used sound waves to connect tiny droplets of liquid metals inside a polymer casing. The novel technique is a way to make tough, highly conductive circuits that can be flexed and stretched to five times their original size.

Making stretchable electronics for skin-based sensors and implantable medical devices requires materials that can conduct electricity like metals but deform like rubber. Conventional metals don’t cut it for this use. To make elastic conductors, researchers have looked at conductive polymers and composites of metals and polymers. But these materials lose their conductivity after being stretched and released a few times.

Keep Reading ↓Show less

Get the Rohde & Schwarz EMI White Paper

Learn how to measure and reduce common mode electromagnetic interference (EMI) in electric drive installations

1 min read
Rohde & Schwarz

Nowadays, electric machines are often driven by power electronic converters. Even though the use of converters brings with it a variety of advantages, common mode (CM) signals are a frequent problem in many installations. Common mode voltages induced by the converter drive common mode currents damage the motor bearings over time and significantly reduce the lifetime of the drive.

Download this free whitepaper now!

Keep Reading ↓Show less