Thursday, October 26, 2006

Naked Eye Classic Takes Off

1. Great reviews including two page spread in Sound on Sound
2. Two distinct, useful voices for loudest guitar or for vocals, horns and percussion
3. Conservatively stated SPL handling
4. A mount that lets you dial in the tone in front of the speaker cabinet
5. A three year no questions asked warranty on Naked Eye Classic
6. High output, low noise, well shielded
8. Open and clear sound that isn't covered by thick cloth like the others. The front sounds very much like a 121 or Fathead, but with a lower noise floor and a larger more efficient transformer, and the back has a rising response similar to the more expensive Studio Vocalist. The two sides are very different!
9. A FULL SIZE transformer made by us and firmly attached. Not a weenie transformer hanging by its wires. Massive SOLID SILVER contact blocks connect the ribbon at both ends and assures an extremely low resistance connection that will last for many years.
10. Low price but higher quality
11. Use any preamp, not just exotic high gain preamps.
12. Designed for everyday use
13. Blue-green muted sparkle finish is durable, and very nice
14. Comes in a very useful case that also holds the Monocle Mount.
15. The one I used for the shakuhachi sessions
16. A great value in a conventional "foil" ribbon microphone today
17. Beats the pants off the nearest competition at about two-thirds of the price, plus you get two mounts and True Dual Voicing.
neumann royer aea akg audio technica sony comparisons

Lung mic array

Looking something akin to a Klingon inspired warrior vest, this microphone array from Deep Breeze listens to lung sounds from 42 separate locations to produce a map of chest wheezing, "cracklies" and sounds that obstructive deseases create during respiration.

This is one of many new developments in medical technology aided by the use of specialized microphonic sensors.

Sunday, October 22, 2006

A Drum, a capsule, and a banjo - a multipart tale of Tizz - Part Four

Well this isn't exactly a banjo. Actually it's a banjo-uke that I picked up at a garage sale many years ago and did some work to. Several of the hooks were missing so I made some to match the originals. Also the thing came with those useless tapered pegs so I filled them in and put four tuners that I took off the Hofner Verithin. I still have the other two in case I ever want to restore the Verithin to original, nonfunctional condition.

Here is our friend the tympanic membrane coupled to some strings. Notice the position of the bridge, which is not in the center. Chladni you think, here he goes again about Chladni. You are right.

The point here is that the position of the excitation matters a lot. What difference does that make in a microphone? Doesn't the whole surface get excited at once? The answer is not in the case of the off axis sound: an off axis wavefront reaches the nearest portion of the membrane first. A sound wave is long until you get to the higher frequencies where the waves can be less than an inch (2.54 cm), which means that the crest of the wave can hit one part of the membrane while the trough reaches the other. This isn't very good because it can get one portion of the membrane to move away from the backplate while the other portion moves toward it, cancelling the sound, and creating a notch function. A couple of posts ago there is a link to Olsen's depiction of exactly that. Here it is again.

Here is a link to a frequency to wavelength converter.

I like the banjo sound up to a point. It certainly has a honky character. That honky character may be in part due to the standing waves on the head. If course guitars, violins etc. all have standing waves too, so why don't they sound like banjos?

A Drum, a capsule, and a banjo - a multipart tale of Tizz - Part Three

Before I get started on the inevitable discussion of the construction and operation of the condenser capsule, a tympanic membrane, let me soften the blow a bit by letting you know that there are still many great pieces of recorded music that I love that were nonetheless made with condenser microphones. Back in the dark ages of the 70's there were many sonic shortcomings in music not the least of which were other sources of noise such as the surface noise of vinyl records, some which I still have and occasionally listen to on my Empire Troubador turntable. I have one particularly crackly copy of "Stand Up", which is a precious treasure.

This is a shot of a typical condenser capsule from an inexpensive microphone. It is well made actually, and certainly a reliable device, capable of detecting sound and converting into an electrical signal for an extended time.

A quick tutorial on how it works: The membrane represents an acoustic impedance mismatch to air. Soundwaves carried through the air impart a force onto the membrane, a varying pressure, which causes it to move. Part of the membrane (not shown here) is coated with a conductive material and one lead is brought to it forming one-half of a variable capacitor. Another lead is bright to the backplate making the other half. A charge is placed across the two halves: either a battery or a DC supply, perhaps 48 Volts or more is present across the two halves. The result is a charged capacitor, that can move.

Now the magic happens: As the membrane moves, its ability to couple electrons, or charge, from one section to another is modulated, and a varying voltage can be detected at the terminals that corresponds with the motion of the membrane. This voltage is then applied to the grid of a tube or the gate of a FET and amplified. It is important to note that the moving membrane does not generate any signal by itself, it only modulates a static, or DC charge. This creates a very sensitive device as the membrane is thin and it takes only the tiniest of movement for it to vary the charge and be heard. In fact it can be made so sensitive that random air molecules can be heard!

Obvious comparisons to the drum can be made, and there are differences, too. The drum is struck by a drumstick, the membrane of a condenser is moved by air. Sometimes that can be a very sharp wavefront with a lot of "kick" like from a kick drum, not surprisingly.

Remember the snare? Those air particles can become agitated and in some instances will produce a noise that rides under the signal. It won't show up in a spectrogram, and it's not harmonic distortion, so it doesn't reveal itself there, either. What it does is create a kind of noise floor that varies with the amplitude. It can be a problem when, for instance, multiple tracks of a vocal are used, as that noise accumulates, and mud and a certain haze or veiled effect can be noticed.

But the number one noise effect has to do with lateral modes, the energy that does not move in and out, but ricochets left and right, and takes time to die down. That's the source of the hissy sound you hear on badly recorded vocals that rides along with the natural breath and throat sounds heard in close mic recording and makes it sound harsh. When it's bad, we refer to it as tizz. Tizz can be subtle, pernicious, and contribute to edgy sounds in horns and violins too.

Tape used to mitigate that effect, but no more, as most music production has gone digital, like it or not. I think the need to overcome what has been revealed - an undesired inherency - is what is driving the continued efforts to make LDCs sound better, and why some cost more than $10,000.

A Drum, a capsule, and a banjo - a multipart tale of Tizz - Part Two

This snare drum is an example of what you can do with a Tympanic Membrane. Tympanic membranes are found in drums, your own eardrum, banjos, dynamic and condenser microphones, and of course, loudpeakers.

Here the randomly picked snare is observed by the Naked Eye microphone, same as used in the shakuhachi sessions.

Tympanic membranes are found singly, or as shown here, as a parallel pair offset and acoustically coupled, aided by a surrounding, fairly air tight seal at the periphery.

The drum, when struck, produces a note, but it is not a single, narrowband note. Instead, it is a very broadband emission with a sharp attack and a lengthy (compared to the excitation of the stick) decay. That decay almost always flattens, notewise, over its period. That's due to a phenomenon known as frequency dependent attenuation, which simply means that the higher frequencies decay, or die out, faster than the lower frequencies.

Tuning the drum by tightening the skin raises the average note, which we can readily hear and appreciate, (or not when badly tuned) but has little effect on the lateral modes, decay, and broadening. I've mentioned the work of Chladni over and over and now would be an appropriate time to revisit him to get further insight into this important acoustic phenomenon.

Not only did Chladni show how the shape of an object affects the propagation of sound across it, but he also seems to have discovered the connection between standing waves, those lateral modes that appear to be still and sometimes bear his name, and what we know today as quantum theory. Chladni also showed that meteorites are of extraterrestrial origin. Quite a guy. Harry Olsen, that famous designer of the RCA ribbon (and other) mics, knew and wrote about Chladni, and did his own diagram of Chladni waves that is quite pertinent here.

Many people imagine the drum and its tympanic cousins as a thing that moves up and down, or in and out, more or less in a uniform fashion. This is not the case at all. In fact, it is the lateral modes, the energy that propagates across the skin, then gets reflected back from the rim, and back and forth again and again until it is radiated or turned into heat, that produce the characteristic sound of the drum.

The snare drum is especially important to music. The snare is a nonlinear coupled mechanical load that generates noise when driven by the drum. That produces a very characteristic and generally high pitched, broad spectrum tshhhhh!! sound that we the children of the late 20th Century love about the snare.

Noise is sometimes hard to define, though it is often thought of as any sound energy that is undesired. The tshhhh!! of the snare is similar sounding to white noise, but it isn't noise (except in muzak) as we think of it.

Still it is important to remember:

1. The drum has a tympanic membrane that produces lateral modes subject to reflection, lengthy decay, and frequency dependent attenuation.

2. The snare drum produces a characteristic, added tshhhh!! as a result of interaction of the tympanic membrane and an adjacent structure.

You can probably see where all this is going. Don't get alarmed. Yet.

Thursday, October 19, 2006

Hugh Tripp and a Tizz demonstration you can do yourself

Hugh Tripp shows how you can do your own investigation of Tizz.

Cut a strip from one sheet of inkjet paper and fold it into a zig-zag like you see in Hugh's left hand.

Cut the remaining piece into a circle.

Listen to the sounds of these objects in a quiet, dry environment. Gently excite the round sheet by wiggling it. What do you hear?

Gently excite the zig-zag by wiggling it and compare the sound against the circle.

You will find one structure will generate more noise than the other one.

A Drum, a capsule, and a banjo - a multipart tale of Tizz

Around the lab we are constantly looking at the how and why of sound. Why does this device sound the way it does? How does the sound propagate and interact with it and how can we modify it to do what we want? These and other questions invade our minds and guide some of our investgations into things acoustic.

Of primary interest is the sound of ribbon microphones. We listen and listen and have convinced ourselves that ribbon microphones are objectively better sounding, with less noise, "tizz" and artifact than the "Large Diaphragm Condenser". We've also learned that acoustic transducers impart a sound quality that is similar to they way the moving element sounds when it is excited by a pulse source, in other words, the color of a microphone inherent to its overall internal timbre, and in many respects this is governed by the same phenomena that makes a good guitar, for example, sound good.

So here now over the course of the following week or so we take a tour into the sounds of Tympanic, Membranous Devices, or Drums, Capsules, and a Banjo, illustrated of course.

But first, we need to answer a common question:

What is "Tizz"?

Tizz is a noise phenomenon that sounds like its name - a ZZZZZZZZ sound that can be hissy, tinny or even boxy, that can be heard on a lot of recordings, and is most notably present in newer digital recordings of the human voice. We humans are good at hearing and identifying voices, and our perceptions are most acute when listening to the voice of someone we know. But this isn't so much about perception as it is about an artifact that occurs when a transducer is moved and lateral modes are generated. Tizz isn't caused by digital recording, but it sure is easier to hear nowadays. Remember our friend Chladni? Lateral modes are found in all transducers to a greater or lesser degree, and they can contribute to Tizz. Tizz rides under the signal and isn't very noticable on tape and at lower frequencies, but digital recording has unmasked tizz and set off a storm of people seeking vocal mics without it. Tizz is so common that it has becme accepted. People expect tizz which is sometimes referred to as "shimmer" and even as "air". But it's noise, and it muddies things up as it accumulates in multiple tracks, and it has become an affectation.

Listen for tizz and you will hear it. copyright robert j crowley

Monday, October 16, 2006

Telefunken Spaceball Surprise

Sometimes, here in microphonium land, things are just too awesome for words. This is one of those things.

It glows in the dark.

Click on the image to enlarge it.

Saturday, October 14, 2006

More Mystery Ribbon Microphones

I like to keep em guessing when we are in the process of introducing and trying out new technology, yet I can't seem to stop myself from talking about it at least a little. Probably the excitement of something new and the need to brag. In any case, we are now in the process of trying out a number of new microphone innovations, some that we have already spoken about in detail such as the nanofilm ribbons and carbon nanotubes, and also some new ideas about how to record such things as kick drums, sonic blasts, jet engines and non-nuclear detonation. Seriously the thing is to keep making ribbon microphones stronger, with higher output and better sound than before, getting that sound to be more useful and exploring the possibilities. Oh yeah, I meant the kick drum application. Hugh has it all figured out, I think...

Here are a couple of our stainless steel bodies in non-standard mounts. These mounts didn't work out well as they were a pain in the neck to attach, so now we have Sticky Lipz mounts which we give away for free with certain mics we make. If you look closely these mics are marked with an X designation indicating they are experimental. Experiments are fun because you can only guess the result and sometimes things work out great, other times they can go up in smoke!

Wednesday, October 11, 2006


This has nothing at all to do with microphones, but if you are up for a little puzzle, check out Vectorpark, a five year old demo of Flash that has been recommended (by me) for collection by MOMA.

See if you can get to the park. Hint: Start with the left bubble, and figure it out. Quite a trip.

Tuesday, October 10, 2006

True Systems and Crowley and Tripp meet at AES

A little back fence chit chat with Tim Spencer of True Systems, makers of the P-Solo and new P-Solo ribbon mic preamplifiers. (which sound great) True Systems used a Studio Vocalist as a demo mic in their booth.

Both companies got a neat new Pro Audio Review award at this year's show. The P-Solo ribbon got an award, and we got one for Naked Eye. Last year we got one for the Studio Vocalist ribbon mic. We'll have to come up with another new product for 07 to make it a streak...

Wednesday, October 04, 2006

Polar Response of the Naked Eye Ribbon Mic and what it means

I'm re-posting Herb Singleton's measurements of the Naked Eye since there have been so many comments and questions about this unique microphone.

What you are looking at is a figure 8 polar response pattern that is plotted with various colors according to frequency. It is like you are looking down on the top of the mic from the ceiling, assuming the mic is set straight upright. Imagine yourself standing where the top of the image is and assume that is the front, or emblem side. You will notice right off that the large dashed white/light colored lines are quite different from the opposite side of the figure 8 pattern. Note that the rear lobe is 180 degrees out of phase with the front lobe - very important to remember when doing A-B comparisons.

At the lower left of the image there is a legend that tells you what frequencies the different lines correspond to, and you have to look pretty closely so I have a zoom function set if you just click on the image. If you are in Firefox you can click it twice and really zoom it to fill your whole screen. The 8000 Hz (Chladnis) dashed line is one that is very different. The others are too, just less so.

What is happening

The different responses on each side are very different, not subtly different, from each other. This is not due to any offsetting (phase shifting) of the ribbon or by placing cloth in front of the ribbon to deaden it. That would lead to loss of definition, something we don't want. Instead, the local field around the ribbon is adjusted using transmission line physics to selectively match the acoustic impedance of the soundwave to the ribbon itself. Sound can be reflected, absorbed, and reradiated from materials such as condenser membranes, ribbons, and virtually everything else, so knowing how the sound energy interacts with the "sensor" is the key to engineering in a desired response or tone. Then it is up to the ear/brain to determine if that tone is a keeper.

Naked Eye is unlike the other ribbon mics that are out in the realm, and was created in response to the Frugal Yankee in us that said people would go for a mic that one one side has a sound somewhat like the Studio Vocalist, which has caused quite a stir, won an award, and ended up on the cover of Recording magazine, and then on the other side, the Proscenium, the mic that has caused its own fervor among the very particular.

What it means

Naked Eye configured this way allows the user to select two different "voices" depending upon application. If you need a rising response, such as for some vocals and acoustic guitars, for example, try the side with the highest response in the upper ranges, easily seen in the graph, or better yet, easily heard. Other apps such as loud electric guitar might sound better with the dark side. You decide. Use your ears! (but protect them for later use) Simply rotate the mic in its mount to change it.

Made in USA

The FTC has this on its website. It describes what it takes to be "Made in USA". Interesting.

Tuesday, October 03, 2006

Crowley and Tripp at AES 2006 - See us at booth number 1431

Here we were at last year's show in NYC. This time we will have the Recordist Ensemble Stereo and perhaps a surprise or two.

Come visit us at booth number 1431, which will probably be near the back, away from the main entrance. AES allocates show space according to seniority and of course, booth size. We have neither.

This year's AES marks our second year of production, and we expect to continue to grow as new microphone technologies are developed and introduced, and we acquire additional products and lines.