Sunday, February 10, 2008

Editorial:Bob Crowley talks about the making of Crowley and Tripp mics, and Roswellite

."Nanotech’ is a buzzword like ‘dot-com’ used to be. But where dot-com had its roots in business, nanotech refers to science – specifically, the control and application of materials on a scale that deals with atoms and molecules. And where dot-com’s hype ultimately ended in a fiasco, nanotechnology is poised to change our lives. The term ‘nano’ has already been tossed around enough to virtually erase its meaning but today we are seeing real evidence of a true nanotech revolution in our chosen fields of music and medical acoustics, with real products – not just buzzwords

Corporate "Escapees"

Hugh Tripp and I linked up with Chris Regan not long after we became ‘corporate escapees’ from a giant, bureaucratic medical device company. I had been director of R&D of the Imaging and Sensing Laboratory, where we invented all kinds of ultrasound devices, and Hugh had been knocking out dozens of precision medical products. We both enjoyed very successful careers. We had music, recording, audio and acoustics backgrounds, and we knew from our experience at Boston Scientific how to make very small things - like the tiny audio transducers used in heart imaging - operate like full-sized surgical tools. It was good, but after a while we got bored with the slowness of a big company. So we looked around and saw the big changes that had happened in audio recording and realised that in all types of microphones, and in particular, ribbon microphones, progress had virtually stopped.
Where's the analog?
Once magnetic recording tape had all but vanished from use, the condenser microphone designs of the past sounded too harsh, too bright and too hard under the dispassionate eye of digital recording. Lower-cost reissues of the classic condensers were delivering a familiar and reliable sound palette, but actual improvements have been few and the condenser technology itself, which is very old indeed, has been so worked over that few fundamental differences exist from brand to brand.
Back to the basics - back to the sound!
A few engineers, musicians and others started exploring the overlooked ribbon microphone as a way to put back ‘a pinch of analogue’ into their digital recordings, and were having success with the current availability of ribbon mics, which are centred on older designs. This availability was put to good use by pioneering recording engineers, and this created a small niche market for new ribbon microphones built by boutique companies. We saw that big improvements could be made to the relatively neglected ribbon microphone world almost immediately.
What a concept! Let the customer tell you what they want.
Users were very up-front with what they liked and disliked about ribbons. In short, they wanted less of a dark sound, which virtually all older ribbons produce, and demanded higher signal output – not just another preamp, but a ‘hot’ transducer. And, last but not least, they said that a much more durable microphone – one that they never had to worry about blowing – was the ultimate goal. The old ‘foil’ ribbons failed on all three counts. If we could correct all of them - we supposed - we would have the answer to ‘ribbon stigma’. The solution, we thought, was in the use of nanomaterials and the application of some of the things we learned in medical research.
"Sounds good" in context
All microphones have timbre. No matter how ‘flat’ or ‘uncoloured’ a microphone is claimed to be, or how straight the curves look, the pickup and delivery of sound is subjected to the transformation process (of acoustic energy into electrical energy) inside every microphone. Curves, traces and charts cannot tell you the whole story of how a microphone will sound in any particular application. The timbre, or tone, of the ribbon mic category has always been dark, so we intentionally designed the acoustics of new ribbon mics to have a brighter sound. For example, using a rising response with vocals would allow them to stand out in a mix. Other voicings include those that give drums a sharp presentation, and also a thick, dense tone that can be optimal for guitar cabinets. Ribbon microphones did not previously cover all of these applications, only some of them.
Hot enough!
Users clearly wanted more output, and by that I mean a strong, high-output, low-noise, hot signal under any recording situation - even quiet sources like soft finger-picking and light vocals. We had to develop our own transformers and other magnetics to do it, but now we enjoy output levels that exceed that of the typical stage dynamic - hot enough for virtually any preamp, IO device, PA system, or even high-end field recorder.
The human sound, presented au naturel
Vocals are a special category - smooth, flattering vocals are actually quite easy to achieve with properly configured ribbon microphones. The ribbon mics we need for vocals should have plenty of air and the rising curve of classic condensers, but without the top end tizz, fizz or hash that is inherent in tympanic membranes used in all condensers. Ribbons are pure and linear, and the human ear can tell the difference. Nobody made a close-range vocal ribbon microphone with a brighter rising response before, but it seemed important to us to produce it.
Nervous Condition? Your Fears Wiped Away With Roswellite
With a firm understanding of how to get certain tone choices, we were left with a final request: ‘Make it so that it will never break’, users said. The ribbons of old were terrible in this regard; some were so delicate that opening a door the wrong way could end a session. Nervous engineers dared not put the ribbon microphone near the source, where it was most needed. An all-new solution was needed to replace the infamous ‘foil’ ribbon. That weakness alone had been keeping the ribbon mic in the locker and away from music making. A better, stronger, great-sounding material, one that wouldn’t break under extreme SPLs, close to a kick drum, wind, or by the accidental application of a 48V phantom power was definitely required.
Ghost of Olsen
The ideal ribbon was imagined by Harry Olson, RCA’s resident audio genius during the late 1920s and early 1930s, as having almost no mass, to be perfectly conductive and yet be as tough as a trampoline. All Olson had to work with was thin aluminium foil, which was, and still is, weaker than any commercial product ought to be. But we had some experience in making the very thin medical devices very strong, and in allied fields such as carbon nanotube arrays, polymeric composites, conductive polymers, and the forming of nanoscaled magnetic and paramagnetic assemblies used in medical implants. If we could combine the strength of these nanocomposites with the conductivity of paramagnetic materials such as gold and copper, then we could obsolete that too-fussy ‘foil’ ribbon, forever.
"With a little help..."
We brought in an extra scientist and engineer, did trial after trial of new process steps, numerous measurements, including accelerated ageing studies, and then put all of that into test microphones and did a lot of listening. Finally, we had what we called ‘Acoustic Nanofilm’. It was light, it was strong, it was superelastic, and it worked. If anything, the sound of this new material was as good or perhaps better than that of foils and it was amazingly tough and resistant to abuse, misapplication of phantom power, plosives and wind blasts – certainly as tough as, or tougher than, a condenser mic. But it was also rather expensive to produce.
Roswellite: Wacky, weird and perfect.
Prior to the release of the first Crowley & Tripp el Diablo and then Naked Eye Roswellite microphones, we started thinking of what we were going to call this material. ‘Acoustic Nanofilm’ sounded too serious, to me. I liked the term ‘Roswellite’ but was afraid it was a little wacky, referring to the supposed UFO crash in New Mexico. My wife works in aerospace and knows about sun-angle-sensors for satellites, but not as much about earth-based microphones. ‘If I told you something was made of Roswellite, what would you imagine it is?’ I asked. ‘Something that is super light, tough and metallic,’ she responded.
It's here...
Roswellite is the trademarked name of our nano-enabled ribbon material invented, by Soundwave Research Laboratories, Inc and that we use in certain Crowley & Tripp microphones, and first introduced as el Diablo Mercenary Edition. It is an extremely strong, low mass, superelastic, paramagnetic composite with high inherent conductivity and shape memory properties. At this moment, we are scaling up production of this material - which is expensive and time-consuming to make - in readiness for the introduction of new microphone models with this and other nanomaterials in the future.


Anonymous said...

doesn't this almost certainly put the aluminum ribbon in the dustbin?

Anonymous said...

Bob and Hugh this is a great story and an inspiration to all. The fact that we witnessed it all at TapeOpCon and in real time here in cyberspace made it all the more delicious to watch you enter and slay the competition with innovation and creativity.


Congratulations on the sale of the mic line to Shure. Medical device companies better watch out!