Field Test: Neumann KM D Digital Microphones

Mar 1, 2008 12:00 PM, By Kevin Becka

INTEGRATED CONVERTERS, DSP AND REMOTE CONTROL VIA AES 42

Polls


Mix Regional

The Mix Regional section for Mix's July 2014 issue focuses on Atlanta. Send us your studio news: updates, sessions, new rooms, club performances and installations. Let the Mix audience know what is going on! Send photos and descriptions to mixeditorial@nbmedia.com.

Since the DAW became an audio standard, the idea of a purely digital signal path from mic capsule to storage medium has interested more than a few engineers. That was all but a pipe dream until 2001, when Neumann — the first company to offer a condenser microphone, switchable directional response, a stereo microphone and 48-volt phantom power — lived up to its pioneering legacy with the release of the D-01 digital mic. The Solution-D large-diaphragm digital mic was truly groundbreaking, offering converters in the mic and supporting the new AES 42 standard to both transmit signal and provide synchronization and remote control of pattern, onboard DSP and other parameters. The beauty of this system is that no mic preamp is needed; gain is strictly digitally controlled in the mic itself.

The next-gen Solution-D model from Neumann, and my review unit, is the KM D Series, a small, front-address pencil mic that offers DSP, switchable capsules and, like its predecessor, remote control. It can be purchased in a nickel or black Nextel finish and comes with Neumann's RCS (Remote-Control Software, Mac/Win). Although it is possible to run the system without the software, I found that it offers a welcome and easy-to-use interface.

DIGITAL SOLUTIONS

The KM 184 D looks much like Neumann's existing KM 180 and KM 100 Series analog mics. It can be operated from 44.1 up to 192 kHz without external converters, and it offers five capsule choices: the KK 131 (free-field-equalized omnidirectional), KK 143 (wide cardioid), KK 145 (cardioid with low-frequency roll-off), KK 183 (diffuse-field-equalized omnidirectional), KK 184 (cardioid) and KK 185 (hypercardioid). To operate, the mic requires a base unit: either the DMI-2 digital microphone interface or one of the less-pricey S/PDIF or AES/EBU connection kits, which can also provide battery power for remote situations. Should you want to take this concept to the next step, this past November RME released the DMC-842, an 8-channel AES 42 interface with a MADI option. At press time, it was rumored that Neumann is working on its own similar interface slated for release later this year.

I had a pair of the KM D digital mics with a few different capsules and used them on several computers and sessions with excellent results. The RCS software loaded easily and communicated with the mics without a hitch. Although I had the full range of connection kits at my disposal, the DMI-2 was the only choice for me, as the smaller, portable connection kit doesn't allow you to change levels or have any other mic control or options. The mic itself will store the DMI-2's settings for use with the smaller connection kits, but I found this scenario unworkable in a session framework where levels may need adjustment at any time. The RCS software is absolutely essential when managing gain as there is no hardware control on the DMI-2. More about that process later.

The software offers basic gain control, level meters and gain-reduction meters,plus some interesting extras. For instance, each mic has onboard DSP in the guise of a compressor/limiter, de-esser and peak limiter, which can be controlled remotely from the RCS interface. There are also three test tones: white noise, pink noise and a 1k tone generated from the mic that can be switched on and off using the software, making troubleshooting an easy venture. A quirky extra is the ability to remotely turn on and off the mic's piercing-blue LED. Although not useful in my setup, I could see where this feature could be tied to other console or DAW functions, such as a Record button, provided that the console or DAW was AES 42 compliant.

AES 42 PIPELINE

I wanted to explore the upper ranges of the mics' sample rates, which required 110-ohm cabling. Neumann states that regulation cabling up to 48 kHz can be used, but the manufacturer recommends an AES-standard 110-ohm cable (up to 300 feet) when you are operating the mics at any sample rate above that. This presented a problem because I was in a studio where the live room had traditional cabling in the walls with no other pass-through access readily available. My enthusiasm for hearing these mics at their best led me to Hosa, which generously provided two 120-foot (and pricey) 110-ohm AES cables so I could run them from my control room, out the door, down the hall and into the studio.

For this setup, the DMI-2 was in the control room next to the computer and was fed by the two cables from the mics. I patched a BNC word clock signal from a Pro Tools HD 192 I/O interface into the DMI-2 to provide a clock source. The DMI-2 has its own word clock that will automatically sync the mics if no external source is available. Next, I fed a Cat-5 cable out of the DMI-2 into the computer via a Cat-5/USB turnaround (provided). This connection was used to communicate to the mics through the RCS software. For the audio connection to the DAW, the DMI-2 sums the two separate AES 42 mic signals and sends them out as an AES stereo pair on a single cable, which I patched into the 192's AES/EBU enclosure input.






Acceptable Use Policy
blog comments powered by Disqus

Mix Books

Modern Recording and Mixing

This 2-DVD set will show you how the best in the music industry set up a studio to make world-class records. Regardless of what gear you are using, the information you'll find here will allow you to take advantage of decades of expert knowledge. Order now $39.95

Mastering Cubase 4

Electronic Musician magazine and Thomson Course Technology PTR have joined forces again to create the second volume in their Personal Studio Series, Mastering Steinberg's Cubase(tm). Edited and produced by the staff of Electronic Musician, this special issue is not only a must-read for users of Cubase(tm) software, but it also delivers essential information for anyone recording/producing music in a personal-studio. Order now $12.95

Newsletters

MixLine

Delivered straight to your inbox every other week, MixLine takes you straight into the studio, with new product announcements, industry news, upcoming events, recent recording/post projects and much more. Click here to read the latest edition; sign up here.

MixLine Live

Delivered straight to your inbox every other week, MixLine Live takes you on the road with today's hottest tours, new sound reinforcement professional products, recent installs, industry news and much more. Click here to read the latest edition; sign up here.

[an error occurred while processing this directive]

The Wire, a virtual press conference offering postings of the latest gear and music news, direct from the source. Visit the The Wire for the latest press postings.