tinyhead Specification

tinyhead portable headphone and microphone amplifier
tinyhead was discontinued in 2014.

Naiant no longer supplies replacement Li-ion batteries for tinyhead.  The replacement battery pack may be purchased directly from its vendor.  The customer must terminate the battery pack to the tinyhead connector.  On request, Naiant can supply replacement connector pins without charge.

tinyhead is dual-mode microphone and headphone amplifier. tinyhead’s master power switch is a three-way switch that functions both as a master power switch and a microphone power selector. When set to microphone mode, tinyhead supplies +6V plug-in power across 7.5kΩ resistance for each channel. In line mode, the microphone power supply is disabled such that the input jack serves as a line input to tinyhead’s headphone amplifier circuit.

tinyhead’s output amplifier is designed for low-impedance headphones and can also drive connected line input devices to +7dBV.  tinyhead has a stereo level control knob that sets gain from -60dB to +32dB.  Maximum input level for tinyhead is 0dBV.

tinyhead’s power LED will glow green when unit is switched on; low battery indicator will continuously light red LED when battery voltage drops to +7.0V (at 20% remaining battery life). Red LED will also briefly light at signal clipping—LED meter threshold may be customized upon request. Standard clip LED setting is 0dBV (7dB headroom above clip indication).

Power options:

  • internal 9V battery
  • internal 9V battery with external DC power jack
  • internal rechargeable lithium-ion battery with external DC power jack

tinyhead may be powered with any type of 9V battery; either alkaline, primary lithium, or nickel-metal hydride (NiMH) rechargeable. However, NiMHs and lower-grade alkaline batteries are not recommended with headphone use at loud volume. High-grade alkaline (Energizer, Duracell, or equivalent) and primary lithium batteries will provide much longer runtime at loud volume.

To access battery, remove rear panel screws and nut on DC power jack (if present). When replacing panel, do not overtorque screws as the case threads may be stripped.

The combined internal 9V battery and external DC power jack configuration may be powered by any DC power supply that supplies between 9VDC and 15VDC, 300mA minimum recommended.

The internal rechargeable lithium-ion battery provides 650mAh at +7.4V, for life of 4.8Wh. The battery is recharged via 2.1mm center-positive power jack. The charger is rated for 100VAC to 240VAC input; US-style plug. International adaptor plugs are not supplied by Naiant. To avoid risk of battery damage and possible fire, charger provided by Naiant (+8.4VDC with regulated charge current no greater than 300mA) must be used to recharge battery. tinyhead can be operated while charging; this may increase charge time.

tinyhead Specifications:

Type: two-channel microphone amplifier with headphone output

Plug-in Power: +6V supplied across 7.5kΩ

Current, no headphone or microphone power load: 5mA
Current, 40mW/channel headphone load: 80mA
Estimated battery life, typical headphone use: >10 hours

Input Impedance: 6kΩ
Output Impedance: <1Ω

Gain Range: -60dB to +32dB

Maximum Input Level, 1kHz @ 1% THD: 0dBV
Maximum Output Level, 1kHz @ 1% THD:

600Ω load: 8mW/+7dBV
300Ω load: 15mW
200Ω load: 22mW
100Ω load: 45mW
50Ω load: 90mW
24Ω load: 180mW
16Ω load: 250mW

Total Harmonic Distortion, direct output, 1kHz @ 0dBV: <0.01%
Crosstalk, 1kHz @ 0dBV: -80dB
Frequency Response: 20Hz to 40kHz
Equivalent Input Noise, maximum gain: -115dBV unweighted; -119dBA

Case size: 3.2″ x 2.1″ x 0.9″ (80mm x 54mm x 23mm)
Weight (with battery): 5 oz (143g)