Neumann USM 69 I Dual Large Diaphragm Multipattern Stereo Microphone

Neumann's USM 69 is a compact switchable stereo microphone for MS and XY stereophony, with freely adjustable pickup angles and selectable directional characteristics. Microphone cable and shockmount are not included with this package.

Neumann's USM 69 i stereo microphone has two separate dual-diaphragm capsules. These are mounted vertically and rotate against each other. The directional polar patterns can be selected separately for each capsule. The capsules operate independently from each other.

Construction

The microphone consists of the amplifier section and the capsule head. The amplifier section contains two microphone amplifiers operating independently from each other. They have an extremely low self noise.

Two completely separate microphone capsules are positioned closely above each other within the capsule head. Their diaphragms are made out of gold-sputtered polyester film. The upper capsule rotates against the lower one over a range of 270°. Color markings on the lower capsule system help to identify the angle by which the upper capsule has been rotated.

When sound waves reach the microphone capsules from different directions they will generate audio signals with different intensity only, but not with time differences, since the capsules are in close proximity and the sound arrives at both capsules simultaneously. The result is an intensity stereo signal that can be summed together for excellent mono compatibility without causing interference.

Polar Patterns

The USM 69 i has two built-in rotary switches. The five polar patterns of both capsules can be selected at the microphone itself. Therefore, no special AC power supply units or powering adapters are necessary.

The two outputs attach directly to any 48 V phantom powered connectors.

In addition to the usual polar patterns: omnidirectional, cardioid, and figure-8, we have added a hypercardioid and a wide-angle cardioid pattern.

A built-in DC converter generates the required capsule polarizing voltages.

Electrical Features

The amplifiers feature high output capability and extremely low self noise. Distant sound sources, as well as very loud sound sources at close range can therefore be recorded without any problem.

Each amplifier has an active filter. It effectively suppresses subsonic interference as caused by wind or structure borne noise. At the same time, the filter prevents the output transformers from overloading through very low frequency energy.

Use as a Mono MicrophoneThe microphones may also be used as completely independent mono microphones. There are many applications when it is important to have a second mono microphone as a backup, or when the outputs of microphones with different polar response characteristics must be available simultaneously.The outputs of the two microphone channels can be linked (cascaded). In addition to the individual directional patterns, other characteristics are available through the combination of both channels.

Use as a Mono Microphone

The microphones may also be used as completely independent mono microphones. There are many applications when it is important to have a second mono microphone as a backup, or when the outputs of microphones with different polar response characteristics must be available simultaneously.

The outputs of the two microphone channels can be linked (cascaded). In addition to the individual directional patterns, other characteristics are available through the combination of both channels.

Operational SafetyBoth microphone systems operate completely independent from each other.The second amplifier will be unaffected, even in case of a faulty ground of the supply voltage for one of the channels, or a short circuit in one of the outputs.The microphone is reliable in mono usage, even if only one of the systems is operated and connected. Its simple and redundant circuitry guarantees a low failure rate. Should the DC converter ever fail, a diode circuit within the microphone ensures that both systems will remain operational. The cardioid pattern is automatically chosen. The sensitivity is reduced by 3 dB.

Operational Safety

Both microphone systems operate completely independent from each other.

The second amplifier will be unaffected, even in case of a faulty ground of the supply voltage for one of the channels, or a short circuit in one of the outputs.

The microphone is reliable in mono usage, even if only one of the systems is operated and connected. Its simple and redundant circuitry guarantees a low failure rate.

Should the DC converter ever fail, a diode circuit within the microphone ensures that both systems will remain operational. The cardioid pattern is automatically chosen. The sensitivity is reduced by 3 dB.

Applications

The USM 69 i condenser stereo microphone is a studio microphone for intensity stereo recording. It is suitable for XY and MS recordings.

Features:

• Switchable stereo microphone
• Two pressure-gradient transducers with double membrane capsules
• MS- or XY-stereophony
• Capsules rotary by 270°
• Very low noise
• Aperture and pick-up angles freely choosable
• Directional characteristics reproducibly switchable, omni, wide angle cardioid, cardioid, hypercardioid, figure-8

Specifications:

• Acoustical operating principle: Pressure gradient transducer
• Directional pattern: Omnidirectional, wide-angle cardioid, cardioid, hypercardioid, figure-8
• Frequency range: 20 Hz ... 20 kHz
• Sensitivity at 1 kHz into 1 kohm: 13 mV/Pa
• Rated impedance: 150 ohms
• Rated load impedance: 1 kohms
• Equivalent noise level, CCIR*: 24 dB
• Equivalent noise level, A-weighted*: 13 dB-A
• Signal-to-noise ratio, CCIR* (rel. 94 dB SPL): 70dB
• Signal-to-noise ratio, A-weighted* (rel. 94 dBSPL): 81dB
  • *According to IEC 60268-1; CCIR-weighting according toCCIR 468-3, quasipeak; A-weighting according to IEC 61672-1, RMS
• Maximum SPL for THD 0.5%**: 132 dB
  • **Measured as equivalent el. input signal
• Maximum output voltage: 3 dBu
• Dynamic range of the microphone amplifier(A-weighted):119 dB
• Supply voltage (P48, IEC 61938): 48 V ± 4 V
• Current consumption (P48, IEC 61938): 2 x 0.7mA
• Matching connector: 5-pin XLR-F
• Weight: 1.12 lbs
• Diameter: 1.18" + 1.89"
• Length: 11.54"
• Stand mount included

NOTE:

Special stereo microphone cable is not included. Accessories like the AC 20 - Y-cable with one XLR 5 F connector and two XLR 3 M connectors - may be purchased separately. Shockmount not available for this model through Neumann.