With modern amplifiers expected to cater for so many new source devices, the Phono capability, once very common, is one of those built-in features that has disappeared in recent times. The engineering team at Creek Audio has always loved the benefits of vinyl records and continues to work on technical and sonic improvements to its range of Phono amp options, be it the stand-alone OBH or Wyndsor or plug-in Sequel types. Tasked with designing a replacement for the long running OBH-15, the team came up with some valuable improvements and additional features; surprisingly they made them all fit into the original OBH-sized casework.
The OBH-15 mk2 has a completely new circuit design, with a discrete transistor MC and integrated circuit MM stage. Unlike its predecessor, the new amp has multiple gain settings and matching capabilities for capacitance and resistance. The signal required by most modern amplifiers is described as being ‘LINE’ level which is, in technical terms, between 200 and 500 milli-Volts sensitivity with a flat frequency response. Unless your amplifier has a specific ‘Phono’ or Disc input, the level will be too low to play vinyl and the frequency response will be wrong.
|THD+noise at 2Vrms output:||MM (40dB gain) @ 1kHz = 0.002%|
MM (40dB gain) @ 10kHz = 0.003%
MM (50dB gain) @ 1kHz = 0.007%
MM (50dB gain) @ 10kHz = 0.007%MC (60dB gain) @ 1kHz = 0.005%
MC (60dB gain) @ 10kHz = 0.005%
MC (70dB gain) @ 1kHz = 0.011%
MC (70dB gain) @ 10kHz = 0.012%
|Channel Separation||MM (all gains) 1kHz = >70dBMC (all gains) 1kHz = >70dB|
|Frequency Response||0.5Hz – 100kHz (+/-0.5dB)|
|SNR||MM (40/50dB gain) = 76/66dB|
MC (60/70dB gain) = 77/70dB
|Overload Margin||MM (all gains)|
21.7dB@50Hz – 21.7dB@1kHz – 21.7dB@20kHzMC (all gains)
20.7dB@50Hz – 20.7dB@1kHz – 20.7dB@20kHz
|Output level||6.1V rms Maximum|
|Output Impedance||100 Ohms|
|Gain||MM = 40dB/50dB|
MC = 60dB/70dB/80dB
|Matching||MM = 100pF or 200pF plus 47k OhmsMC = 100pF or 1100pF plus 100 Ohms or 510 Ohms|
|Size||100 x 63 x 150mm WxHxD|
|Weight||1.0 kgs inc OBH-Uni power adapter|
|Power consumption||3 Watts|
|Mains voltages||100V to 250V AC 50/60Hz|
|Mains Connection||A clip-on plug is supplied for UK, North America and Europe|
|Finish Colour||Black Front Panel|
The OBH-15 mk2 is small device designed to boost the signal and introduce an R.I.A.A. frequency response characteristic to provide the most accurate reproduction of the recording.The OBH-15 mk2 is 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 extruded black aluminum case is fitted with turned aluminium disc feet and sound absorbing Bumpons.
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.