The U series was discontinued in 2012.

10mm U series capsules may be converted to the X-R system.

The U system is a fully interchangeable and interoperable capsule and amplifier system. U amplifiers convert +12V to +48V phantom power to +9V plug-in microphone power, and generate a buffered, low-impedance output. U capsules may be used with phantom-powered U amplifiers, or can also directly connect to plug-in powered microphone inputs.

The U-D, U-M, and U-S capsules may be visually distinguished by jack color (U-D and U-M use silver, U-S uses gold), and side vent holes on the U-D capsule. U capsules may be distinguished from the X-S microphone by the powdercoated finish of the U series (the X-S has a glossy enamel finish). The U-C, U-Q, and U-O capsules may be distinguished by the presence of six vent holes on the U-C capsule and three vent holes on the U-Q capsule.

Warning: do not connect U capsules directly to phantom power using the X-S microphone’s adaptor cable. U capsules are not designed to directly interface with phantom power, and may be damaged if exposed to voltage in excess of +12V!

The U-C, U-D, U-M, U-Q, U-S, and U-W capsules contain electronic de-emphasis filters that are designed for 4.8KΩ load impedance (supplied by all U series amplifiers, and tinybox’s plug-in power input). When connected to a plug-in power microphone input that has significantly different impedance, the capsules’ frequency response will not meet the specifications below. Upon request, the de-emphasis filters may be omitted, and any required de-emphasis should be performed in post-processing.

U capsule measurements taken connected to U-A amplifier; noise measurements taken connected to U-T amplifier.

U-C specification

The U-C is designed as a general-purpose directional microphone, for use on any source where off-axis rejection is important.

Type: 10mm cardioid electret condenser microphone
Power: +3V to +10V on ring connector
Current: 0.5mA
Sensitivity, 1kHz @ 94dBSPL: -41dBV/Pa
Total Harmonic Distortion, 1kHz @ 94dBSPL: 0.1%
Maximum Level, 1kHz @ 1% THD: 132dBSPL
Frequency Response @ 1m (-3dB): 100Hz to 20kHz
Polar Response, 180°: -11dB @ 1kHz
Self-Noise: 18dBA
Weight: 0.4oz (10g)
Dimensions: 1 1/4″ x 1/2″ø (32mm x 12mmø)

U-D specification

The U-D is intended for use on loud sources where off-axis rejection is important, and low sensitivity and attenuated high frequency response is desired. The U-D offers a tone similar to dynamic microphones in a much smaller size.

Type: 6mm cardioid electret condenser microphone
Power: +3V to +10V on ring connector
Current: 0.3mA
Sensitivity, 1kHz @ 94dBSPL: -47dBV/Pa
Total Harmonic Distortion, 1kHz @ 94dBSPL: 0.1%
Maximum Level, 1kHz @ 1% THD: 136dBSPL
Frequency Response @ 1m (-3dB): 200Hz to 12kHz
Polar Response, 180°: -10dB @ 1kHz
Self-Noise: 28dBA
Weight: 0.4oz (10g)
Dimensions: 1 3/8″ x 3/8″ø (36mm x 9mmø)

U-M specification

Using the same capsule as Naiant’s well-regarded X-M microphone, the U-M offers flat diffuse-field frequency response and excellent transient response for realistic and accurate recordings.

Type: 6mm omnidirectional electret condenser microphone
Power: +3V to +10V on ring connector
Current: 0.3mA
Sensitivity, 1kHz @ 94dBSPL: -32dBV/Pa
Total Harmonic Distortion, 1kHz @ 94dBSPL: 0.1%
Maximum Level, 1kHz @ 1% THD: 126dBSPL
Frequency Response (-3dB): 20Hz to 20kHz
Polar Response, 180°: -3dB @ 12kHz
Self-Noise: 21dBA
Weight: 0.4oz (10g)
Dimensions: 1 3/8″ x 3/8″ø (36mm x 9mmø)

U-O specification

The U-O’s larger 10mm capsule offers lower noise and more mellow response than 6mm microphones. It is recommended for quieter acoustic sources.

Type: 10mm omnidirectional electret condenser microphone
Power: +3V to +10V on ring connector
Current: 0.5mA
Sensitivity, 1kHz @ 94dBSPL: -37dBV/Pa
Total Harmonic Distortion, 1kHz @ 94dBSPL: 0.1%
Maximum Level, 1kHz @ 1% THD: 126dBSPL
Frequency Response (-3dB): 20Hz to 14kHz
Polar Response, 180°: -3dB @ 12kHz
Self-Noise: 15dBA
Weight: 0.4oz (10g)
Dimensions: 1 1/4″ x 1/2″ø (32mm x 12mmø)

U-Q specification

The U-Q is intended for quieter sources where off-axis rejection is critical. The U-Q’s far-field low frequency rolloff helps reject ambient noise sources. When placed close to a quiet source for maximum signal-to-noise ratio, the U-Q’s proximity effect will yield a natural sound on the source while maintaining far-field low frequency and off-axis rejection.

Type: 10mm cardioid electret condenser microphone
Power: +3V to +10V on ring connector
Current: 0.5mA
Sensitivity, 1kHz @ 94dBSPL: -36dBV/Pa
Total Harmonic Distortion, 1kHz @ 94dBSPL: 0.1%
Maximum Level, 1kHz @ 1% THD: 126dBSPL
Frequency Response @ 1m (-3dB): 250Hz to 20kHz
Polar Response, 180°: -11dB @ 1kHz
Self-Noise: 15dBA
Weight: 0.4oz (10g)
Dimensions: 1 1/4″ x 1/2″ø (32mm x 12mmø)

U-S specification

The U-S capsule’s lower sensitivity is especially suited for close-micing louder sources where a natural tone is desired and off-axis rejection is less important.

Type: 6mm omnidirectional electret condenser microphone
Power: +2V to +10V on ring connector
Current: 0.3mA
Sensitivity, 1kHz @ 94dBSPL: -43dBV/Pa
Total Harmonic Distortion, 1kHz @ 94dBSPL: 0.1%
Maximum Level, 1kHz @ 1% THD: 132dBSPL
Frequency Response (-3dB): 30Hz to 20kHz
Polar Response, 180°: -3dB @ 12kHz
Self-Noise: 25dBA
Weight: 0.4oz (10g)
Dimensions: 1 3/8″ x 3/8″ø (36mm x 9mmø)

U-W specification

The U-W’s pressure waveplate creates an acoustic on-axis high-frequency emphasis, which enhances the directional response of the microphone and improves on-axis signal to noise ratio. The U-W is thus designed for recording acoustic ensembles at moderate distances, but is also indicated for use on solo instruments.

The standard U-W capsule contains an electronic de-emphasis filter to generate the specified frequency response; however, upon request the de-emphasis filter may be omitted. In that case, de-emphasis should occur as a final processing step, which can reduce total system noise.

Type: 6mm omnidirectional electret condenser microphone with pressure waveplate
Power: +3V to +10V on ring connector
Current: 0.3mA
Sensitivity, 1kHz @ 94dBSPL: -33dBV/Pa
Total Harmonic Distortion, 1kHz @ 94dBSPL: 0.1%
Maximum Level, 1kHz @ 1% THD: 122dBSPL
Frequency Response (-3dB): 20Hz to 20kHz
Polar Response, 180°: -3dB @ 3kHz
Self-Noise: 19dBA
Weight: 0.6oz (17g)
Dimensions: 1 3/8″ x 3/8″ø (36mm x 9mmø)
Dimensions (disc): 1/4″ x 1 7/16″ø (6mm x 36mmø)

U-8S specification

The U-8S capsule contains two 16mm cardioid capsules that are separately routed to tip and ring connectors, and thus may be used independently via the U-A or U-L amplifiers, or directly to a plug-in powered microphone input. The two resulting signals may be used as a stereo recording, or mixed to create a mono multipattern microphone.

When connected via a U amplifier to a single channel microphone preamplifier, the U-8S will yield a bidirectional (figure-8) pattern. When connected via the U-8A amplifier, the U-8S can generate a continuously variable polar pattern. The capsule marked with the blind hole is positive polarity output (front) when used with a U amplifier.

When used as a single-point stereo microphone, the capsule side marked with the blind hole is routed to ring (pin 2 output on a U amplifier; red ring XLR-M on U-SO cable) and thus should be treated as right channel.

Type: 16mm bidirectional electret condenser microphone
Power: +3V to +10V on tip and ring connectors
Current: 0.8mA total for tip and ring connectors (0.4mA each pin)
Sensitivity, 1kHz @ 94dBSPL: -40dBV/Pa
Total Harmonic Distortion, 1kHz @ 94dBSPL: 0.1%
Maximum Level, 1kHz @ 1% THD: 126dBSPL
Frequency Response (-3dB): 150Hz to 20kHz
Polar Response, 90°: -10dB @ 1kHz
Self-Noise: 18dBA
Weight: 1.2oz (33g)
Dimensions: 2″ x 1 1/4″ x 3/4″ø (50mm x 32mm x 19mmø)