Recording - June 2010 - 14

Cloud Microphones

The wiring from the motor assembly to the transformer is twisted together for low inductive pickup, but it’s still flexible which is definitely a problem; any movement of that wiring is going to be a source of distortion. On the other hand, the way the body is designed, using a stiffer wire would reduce the effectiveness of the internal shock mounting, which on this mic is a big plus. Again, I’m told this is something Cloud has addressed in their newest shipping models, which have stiffer wire and a slightly reworked shock mount to counter its negative effects. How does it measure? It’s difficult for me to do detailed measurements on figure-8 microphones because I have only a small hemianchoic chamber, so I sent it off to a friend with a full chamber. The on-axis frequency response is very much how you would expect, a fairly flat line up until about 7 Khz and then a dropping, somewhat ragged response above that. Approximately what you’d see if you looked at a large ribbon mic like a 44 or 77... the mass of the ribbon is the main contributor to the top-end dropoff, which is how it’s supposed to be. The front and back responses were absolutely identical, which is a good thing, but one thing I noticed was that the null on the right side was about 10 dB better than the null on the left side. Both nulls were very good, but I think there is some asymmetry involved, possibly the result of sound bouncing around on the bottom part of the case where the transformer is; packing this part of the mic body with cotton wool would help a lot to remove that and make it more symmetric. Cloud’s latest mics have sound-absorbing lining that reportedly helps this. Sensitivity was lower than an SM57 but really quite respectable for a ribbon mic. The microphone passed the usual RF test (2 watts at one foot on 146 MHz) without any problem, although the accompaning Cloudlifter pre-preamplifer (see below) did not. I did expect to see a divot in the top end resulting from reflections off the surface of the magnet, but honestly I didn’t see anything at all. That’s a nice sign... some careful work has gone into this microphone. Ribbon mics have low output... live with it This mic is a little more sensitive than most of the older classics, but it still has very low output compared with a modern condenser or a lot of modern moving-coil dynamics.
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RECORDING JUNE 2010

Now, all the time I hear from people “I can’t use this microphone because I have to turn the gain on my expensive mic preamp all the way up.” This is foolish. The reason you buy an expensive mic preamp in the first place is so it sounds good, even at high gains. Just turn it up and it’ll sound fine. If you’re limited to one of those inexpensive console preamps where the bass response changes when you adjust the gain trims, you probably won’t be happy with any conventional ribbon microphone because the preamp just won’t sound good with the gain up all the way. Don’t blame the mic, blame the console. This mic does work just fine into inexpensive solid-state input preamps like the Symetrix 302, and into better console preamps. So do old RCA mics. Just turn the gain all the way up and relax.

The Cloudlifter is also a reasonable device to use with any ribbon mic that wants to see a higher input Z, like in fact all the old RCA ribbons. If you’re using ribbon mics on stage or in a situation where you are often moving from one studio to another, the Cloudlifter will help you get the best sound out of the ribbon in a very wide variety of environments. The JRS-34 active ribbon mic As I mentioned before, Cloud also makes the JRS-34, which has the same PC board that the Cloudlifter uses, built inside the microphone. Interestingly, the asymmetric nulls were a little bit worse inside this mic than on the JRS-34-P, which reinforces my belief that the asymmetry is the result of sound bouncing around down at the bottom of the case. But in terms of actual sound quality, I couldn’t tell the difference between the JRS-34-P with the external Cloudlifter and the active version of the mic. The active version of this mic is a little more convenient if it’s going to be your primary (or only) ribbon, but the Cloudlifter is a tool that you can use on any ribbon microphone (and even some dynamics), so if you intend on having a good closet of different ribbon mics it would cost about the same and give you more flexibility if you take the external route and buy the passive mic with the Cloudlifter. Conclusion This mic isn’t a 44B or even a 77DX.... but it’s a lot less expensive and will probably be more reliable than one of those, and it will give you a lot of the sound of those mics. It’s clearly designed out of the old RCA tradition with some sacrifices to bring costs down. AEA will sell you an absolute copy of the 44B, and it will give you more of that traditional RCA sound, but its cost is an order of magnitude higher. This Cloud mic will give you a substantial part of that sound at a reasonable price. This is not one of the cheap Asian-made ribbon microphones flooding the market right now, and actual engineering has gone into the acoustical design. Some folks set out to make a mic with a particular sound, and these folks did, instead of starting out with a bunch of mic parts and seeing what kind of sounds they can get from them like the Asian folks do. The world needs more of this kind of vision. Prices: JRS-34-P, $1499; Cloudlifter, $329; JRS-34, $1799 More from: Cloud Microphones, www.cloudmicrophones.com. Scott Dorsey (dorsey@recordingmag.com) is a recording engineer, producer, audio equipment designer, and lover of ribbon mics, living and working in Williamsburg, VA.

The Cloudlifter If you have a console preamp with an input transformer, you may have too low an input impedance for a ribbon mic to be happy. Likewise, some console preamps may just not have enough gain. For this, Cloud makes a neat gadget called the Cloudlifter Pre-Preamplifier. It’s a box containing a phantom-powered four-FET balanced amplifier that goes between the mic and preamp and gives you not only a very high-Z balanced input (so the mic sees very little load, but still has good noise rejection from the balancing), but also gives you about 20 dB added gain. The Cloudlifter seems to add little noise and while the common mode input rejection isn’t as good as in some preamps, it’s respectable enough unless you are working in high-RF environments. While being tested at one location, it did pick up an odd squealing from a targeting radar at a local military base, but so do guitar amps out in that area as well.

http://www.cloudmicrophones.com

Recording - June 2010

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