How Ribbon Microphones Became Popular Again

Ribbons were the first great microphones, mainly due to their very musical, natural sound qualities. Invented in the 1920s, their run of popularity lasted until the 1960s when ribbons fell out of favor. That was not because of the microphone itself, but due to changes in the way voices and music were recorded. Now ribbons are back in favor. How did that happen?

Ribbon microphones have a long and storied history in broadcasting and recording. Drs. Walter H. Schottky and Erwin Gerlach co-invented the first ribbon microphone at Telefunken in the 1920s. Dr. Harry F. Olson of RCA started developing ribbon microphones using field coils and permanent magnets a few years later.

The first RCA ribbon mic was manufactured in 1931. A year later, RCA ribbon mics were used at Radio City Music Hall in New York City. In 1933, the RCA 44-series came on the scene and lasted through the 1970s, when RCA ended its run in the microphone business.

All ribbon mic recording session

All ribbon mic recording session

Because ribbons have an inherent, high-frequency roll off that is similar to the way people hear, they remain popular to this day. Between the 1930s and 1990s, the majority of people were recording to tape machines through consoles. Both had a high-frequency roll off. Those tapes were then put on vinyl, which also added more roll off in the high-frequency range.

Then those vinyls were played on radio, which added even more high-frequency roll off. By the time the original source track hit the home listener, much of the high-frequency content was totally gone.

Until the late 1950s, condenser microphones could not compare to the ribbon’s frequency response. But condensers steadily improved and found their way increasingly into recording studios. Because of their high-tuned system, frequencies in condensers in the top-end were exaggerated and hyped.

Some condenser mics sounded harsh. But by the time the condenser was recorded to tape, then transferred to vinyl and then played back on radio, the top end was greatly rolled off and sounded smooth.

AEA replica of the RCA 44BX, $3,780

AEA replica of the RCA 44BX, $3,780

The difference between a condenser and a ribbon at the end of the chain was pretty drastic. An RCA 44BX sounded muddy next to a condenser, which sounded crystal clear.

Then, in the 1990s, something dramatic happened. Digital recording started to replace analog tape machines. It was much more transparent and honest sounding than tape machines. Suddenly, engineers found that the condensers they had been using for years for analog recording sounded too harsh and brash when going directly to digital converters.

Realizing that the unaltered sound of digital recording complemented the natural roll off of their ribbons, many users searched their microphone lockers for vintage ribbons. What they found was a warm, mellow and pleasing sound — one that is well suited to digital recording technology.

Wes Dooley, AEA's founder

Wes Dooley, AEA's founder

In 1998, AEA’s Wes Dooley began production on a replica and upgraded version of the classic RCA R44BX, called the R44C. Since then, AEA and other ribbon companies have designed a range of new ribbon models that have been much improved over earlier microphones.

For one thing, the current generation of ribbon microphones are far more rugged. Improved construction materials, stronger magnets and updated designs dramatically improved the mics. Ribbons can now be used anywhere, including on location.

AEA R8, small, new generation, active microphone, $1,098

AEA R8, small, new generation, active microphone, $1,098

One of the most important new improvements is active circuitry in ribbon microphones. Traditionally, all ribbon microphones were passive, meaning they needed no phantom power to operate. Earlier models were of a simple design, consisting of a thin aluminum ribbon, two magnets and a transformer. That was it.

But for traditional, passive ribbon mics to reach their full sonic potential, they needed a very high-gain, high-impedance microphone preamp. Those preamps were of an earlier era; today’s most affordable preamps lack the high gain.

Rode NTR ribbon Mic, $799

Rode NTR ribbon Mic, $799

Pairing a passive ribbon mic with a preamp that has a low input impedance can have a negative affect on the low-end, transient response and overall frequency response of the sound. This can be a problem when recording quiet sources without excess noise.

These factors led to the development of active ribbon microphones. These are identical to older design passive mics with two major differences — they have internal electronics that boost the mic’s output level and maintain a consistent impedance over the entire frequency spectrum. To operate this circuitry, active ribbon microphones require standard 48-volt phantom power.

Active ribbon microphones have about 12dB more gain, a better signal-to-noise ratio and a consistent impedance without regard to the type of external mic preamp used. These microphones can be used with any preamp and the frequency response sounds very consistent. Engineers can add color and saturation using their preamps without worrying whether the device will affect the bass response of the microphone.

Today, active ribbon mics are more compact, lower in cost, lighter in weight, extremely rugged and can plug-and-play with any modern preamp. Most important, their sound is dramatically better and more natural than condenser microphones with digital technology.

Royer R-10 passive ribbon mic, $499

Royer R-10 passive ribbon mic, $499

Ribbon mics, both active and passive, have made a big comeback and many studios now base most of their mic locker around them. A new generation of preamps are now ribbon friendly. Ribbon microphones are now the foundation for albums ranging from Hollywood movie scores to rock records. And, just as in the early days, ribbons make the human voice sound like “the voice of God.”

You might also like...

Designing IP Broadcast Systems - The Book

Designing IP Broadcast Systems is another massive body of research driven work - with over 27,000 words in 18 articles, in a free 84 page eBook. It provides extensive insight into the technology and engineering methodology required to create practical IP based broadcast…

Demands On Production With HDR & WCG

The adoption of HDR requires adjustments in workflow that place different requirements on both people and technology, especially when multiple formats are required simultaneously.

NDI For Broadcast: Part 3 – Bridging The Gap

This third and for now, final part of our mini-series exploring NDI and its place in broadcast infrastructure moves on to a trio of tools released with NDI 5.0 which are all aimed at facilitating remote and collaborative workflows; NDI Audio,…

Designing An LED Wall Display For Virtual Production - Part 2

We conclude our discussion of how the LED wall is far more than just a backdrop for the actors on a virtual production stage - it must be calibrated to work in harmony with camera, tracking and lighting systems in…

Microphones: Part 2 - Design Principles

Successful microphones have been built working on a number of different principles. Those ideas will be looked at here.