High-end standalone headphone amp Creek Audio has been making headphone amplifiers since 1993 and therefore understands what is needed to make them sound good. The OBH-21 mk2 is the latest in the long history, being small and very stylish. Designed to complement the Creek full sized range, it has an impressive solid aluminium front panel with either a silver or black finish. Its housed in a custom black metal case is fitted with turned metal disc feet and sound absorbing cushioned feet. The OBH-21mk2 is essentially a very high quality miniature integrated amplifier, designed specifically to drive two pairs of low impedance headphones simultaneously from a line level source, such as a CD player, DAC, or amplifier without headphone output. It can even drive demanding 8 Ohm headphone if called upon to do so. Unusually, it is also designed to act as a single input high quality pre-amplifier, if required. Its output level is controlled by an ‘audiophile quality’ ALPS 27mm Blue Velvet volume control on the front panel and by user adjustable gain setting switches on the bottom of the case. The OBH-21mk2 has three pairs of stereo RCA sockets on the rear panel for Line level input, looped Line level output, and a variable pre-amp output, whose gain can be set, independently from the headphone gain for the greatest flexibility. OBH Uni Power Supply Adaptor The OBH-Uni is a multi-region, 24V, 0.5A power supply adaptor. Creek originally developed this power adaptor to simplify the requirements for selling OBH products in all countries. However, extensive listening tests and comparisons proved that this high efficiency regulated power adaptor can also extract the best performance from all of Creek’s OBH products. This includes the latest OBH-15mk2 Phono Pre-amp, which has high-gain and is therefore more demanding of its power supply’s purity. It is supplied with three different snap-on power-plugs suitable for Europe, UK and USA. The snap-on head on the latest version of OBH-Uni uses a 2 pin, figure 8 connector, so it’s possible to use a 2 pin figure 8 extension power cord, with alternative mains plugs on the end. It provides a stable output from any input mains voltage range from 100 – 240V. Strict international regulations make it unacceptable to use conventional linear power adapters because, if they are left permanently switched-on, their standby power will definitely exceed the 0.5W limit. The latest OBH-Uni draws less than 0.5W when idle, or plugged-in but not used. It is also silent in operation, from zero to maximum current consumption.
Features and Specifications:Output Power: > 100mW / 8 Ohms, > 160mW / 16 Ohms, > 200mW / 33 Ohms, > 210mW / 68 Ohms Headphone Impedance: 8 to 1k Ohm Output Impedance: 1 Ohms Input Impedance: > 7 k Ohms Frequency Response: 10 Hz to 50 kHz THD Headphone Out < 0.002% from 20 Hz to 20 kHz at 0.5V into 68 Ohms SNR Headphone Out 116dBA ref 1V, 107dBA at 12.5dB gain THD Pre-amp Out: < 0.0006% from 20 Hz to 20 kHz Crosstalk Line Out: > -80dB, 10Hz – 20 kHz Line out Crosstalk Headphone Out: > -60dB headphone output – 33 Ohm Gain Settings: 0dB, 6dB, 10dB and 12.5dB Power Consumption: < 6 Watts at max power, < 0.5 Watts standby Power Supply: 24V DC 12 Watts max Size (W/H/D): 7″ x 3.75″ x 2.25 inches Weight: 22 ounces