Neumann KM D Digital Microphone

The concept of a digital microphone opens the door to a whole realm of possibilities … as well as potential problems.
Author:
Updated:
Original:


(click thumbnail)The concept of a digital microphone opens the door to a whole realm of possibilities … as well as potential problems. Yet Neumann is the perfect candidate if someone is going to do it right. Neumann — a historic innovator in modern microphone development — is on my short list of companies that continue to excel in the microphone production arena.

The Solution-D project was Neumann’s initial introduction into the small world of digital microphones. It resulted in the D-01, a large-diaphragm variable-pattern digital mic. The D-01 has the look of a traditional Neumann microphone, plus it provides a direct digital output. Now the technology from this mic has been applied to the new modular small-diaphragm KM D mic series ($2,149 for a starter set of a KM 184 D with choice of AES/EBU or S/PDIF connection kit).

The series includes three models that resemble the original analog KM 180 series, both physically and in model numbering. But, unlike their analog counterparts, the digital models are modular with interchangeable capsules from the KM 100 series. The KM D is available in classic nickel or black nextel finish.

Features

The heart of this digital microphone system is the KM D body, which contains the digital head-amp and output stage. It can be combined with any of three interchangeable capsules to form the KM 183 D omni (diffuse field equalized), KM 184 D cardioid or the KM 185 D hypercardioid mics. Neumann has recently added three more capsules to the line — the KM 131 D free field omni, KM 143 D wide cardiod and KM 145 D cardiod with LF roll off for speech. In 2008, a figure-8 KM 120 D will be added, as well as various extension tubes and other accessories.

Solution-D mics comply with the international AES 42 standard that has been extended from the AES 3 (AES/EBU) standard to include phantom power for the microphone, remote control and synchronization data, as well as user bits for the receipt of microphone control data. The mics feature an exceptionally clean, uncolored sound with very low self-noise and an extensive dynamic range. A patented 28-bit process performs the analog-to-digital conversion.

Fast FactsApplications
Studio, project studio, broadcast, postproduction, ENG, film

Key Features
Comply with the AES 42 standard; KM D body with digital head-amp and output stage; KM 183 D omni, KM 184 D cardioid, and the KM 185 D hypercardioid interchangeable capsules; patented 28-bit A/D process; Neumann Remote Control Software (RCS)

Price
Starter Set — $2,149; Single mic — $1,949; Stereo set — $3,769; Capsule head — $779, DMI-2 $1,365, Connection kit $259.

Contact
Neumann | 860-434-9190 | www.neumann.com

PRODUCT POINTS

PLUS

  • Sounds like a quieter version of the KM-100
  • Beyond a normal capacitor capsule range, yet neutral, transparent and linear
  • Remote Control Software (RCS) and the DMI-2 interface

MINUS

  • RCS initially takes more time to control than traditional hardware

Score
The KM D Series is an amazing microphone package with unparalleled performance, amazing flexibility.The mic supports sampling rates of 44.1, 48, 88.2, 96, 176.4 and 192 kHz, and has a frequency response of 20 Hz - 20 kHz. The Equivalent noise level (listed in this order: omni capsule/cardioid capsule/hypercardioid capsule) is 24/22/24 dB, and the equivalent A-weighted noise level is 13/13/15 dB. The signal-to-noise ratio is 70/72/70 dB, and the signal-to-noise ratio A-weighted is 81/81/79 dB. The Maximum SPL at 0 dBFS is 135/133/137 dBSPL. The dynamic range is 122/120/122 dB.

The mic can be used with the S/PDIF Connection Kit (which provides S/PDIF digital output), the AES/EBU Connection Kit (which provides AES/EBU digital output), or the DMI Digital Interface (which provides AES/EBU digital output).

The ability to use the Neumann Remote Control Software (RCS) is one of the primary strengths of the KM D Digital Mic. It requires the DMI-2 Digital Interface plus a PC (running Windows 98 SE, ME, 2000 or XP) or a Mac (running OS 8.6 or higher and CarbonLib version 1.6 or higher), a free USB port, 10 MB of free hard disk space, graphics resolution of 1024 x 768 or higher, HiColor or TrueColor, a CD-ROM drive, a mouse, and Adobe Acrobat Reader (to access the manual).

RCS is a universally applicable remote control software package for digital mics that operate in accordance with the AES 42 standard. The software displays all of the controllable functions and status indicators on the screen in easy to navigate channel strips that resemble a mixing console. The number of channels displayed is selectable from two to eight and is independent of the number of microphones controlled. All of the channel settings can be saved in configuration files for later retrieval. The current settings are automatically saved each time the software is closed, and are reloaded the next time it is started.

The software allows computer control of several parameters, including Low Cut filter, Pre-attenuation, Gain, Peak Limiting and Compression. If the Low Cut filter is activated, it can be set to 40 Hz, 80 Hz or 160 Hz. The Pre-attenuation is achieved by reducing the capsule voltage. If it is activated, the dynamic range is shifted by the corresponding value to higher sound pressure levels. The Gain parameter is carried out entirely in the digital domain, thus avoiding the additional noise and possible effects on the sound that can occur in analog processing. It is adjustable from 0 dB to +63 dB in 1 dB intervals.

The Peak limiter includes an adjustable threshold (-15 dBFS to 0 dBFS in 1 dB intervals) and a fixed attack time (-160 £gs) and release Time (< 0.1 s). The Peak Limiter provides very effective overload protection against peaks, which occur primarily as individual peaks. This facilitates easy, uncomplicated setting of the gain at the microphone, based on the effective level conditions. This is particularly helpful, for instance, when working without remote control only with the settings saved in the DMI. Even when switched off, the Peak Limiter remains active at the 0 dBFS threshold.

The Compressor/Limiter can function in a broad band, or as a high-frequency compressor/limiter (de-esser) in one of three selectable frequency ranges (> 1 kHz, > 2 kHz or > 4 kHz). The ratio can be set to 1.2:1, 1.5:1, 2:1, 4:1, 6:1, 8:1 or >100:1. The threshold is variable from -63 dBFS to 0 dBFS in 1 dB intervals. The attack time can be set to 0 ms, 0.1 ms, 0.3 ms, 1 ms, 3 ms, 10 ms, 30 ms, or 100 ms and the release time can be set to 0.05 s, 0.1 s, 0.2 s, 0.5 s, 1 s, 2 s, or 5 s. In addition, the sampling rate, the synchronization mode, test signals, the polarity of the output signal and the LED can be controlled remotely via the RCS. Internal microphone software revisions can be updated via the Neumann DMI-2.

In Use

I initially tested one of the mics with the AES/EBU connection kit. I put it to work recording a Taylor 514-CE acoustic guitar and it sounded wonderful. I tried all three capsules, and in each instance was impressed with the result. Although I don’t own a set, I’m fairly familiar with the KM 100 series of microphones and the KM D sounds like a quieter version of the KM 100.

The most decisive factor of a digital mic is the A/D converter stage, and from listening to this microphone it appears that Neumann has nailed it. This mic achieves a dynamic range beyond that of a normal capacitor capsule, yet it remains neutral, transparent and linear. The A/D converter is located directly next to the capsule, which provides the best A/D conversion available. The converter’s dynamic range exceeds that of the capsule and it adds no coloration. Between the mic pre and the analog-to-digital conversion, an analog microphone’s dynamic range is typically reduced by about 25 dB. Neumann’s A/D in the Solution-D series is a true 28-bit conversion that provides the microphone’s full dynamic range and is output as a 24-bit signal in the AES42 format. The DMI-2 interface controls the microphones and outputs the signal as standard AES3.

Using the mics along with the RCS and the DMI-2 interface is what I was really excited about, so I quickly made the move to installing the software on my MacBook Pro. The installation was quick, painless, and I was remotely controlling the mics in just a few minutes. The software has a great interface and is simple to use. The features are clearly labeled and overall it is very intuitive. I found it quick and easy to make level adjustments, add compression, adjust the pre-attenuation, insert the low cut filter, etc. It is even possible to remotely switch the power light on the microphone on and off, or change its brightness.

My hope is that mixer and computer interface manufacturers will quickly realize the importance of the AES42 interface and will begin to include it on their products, which in this case will eliminate the need for the DMI-2 interface.

During my review period, I had the opportunity to use the mics on drum overheads, piano, acoustic guitar and on a small choir. In every instance, I was absolutely thrilled with their sound. The only downside from my perspective is that I’m still not as fast with the RCS software as I am with traditional hardware, so at times I felt that I was dragging the session. This will change with more use and the software allows presets to be saved, thankfully; having a starting point that is relatively close to your desired settings is viable.

The integral digital limiter is another one of the system’s strong points. It is nearly transparent yet it is 100-percent effective in preventing overloads. This is handy when doing typical tracking sessions, but indispensable when doing critical direct to stereo recording.

Summary

The Neumann KM D Digital Microphone series is an amazing sounding microphone package providing unparalleled performance and amazing flexibility (especially if multiple capsules are purchased). At first glance the package appears to be a bit pricey, but when you take into consideration that the mics don’t require mic preamps, analog compression or high quality converters, they are a bargain.