Creek OBH-8 MM Phonostage
Employing state-of-the-art circuitry and high grade components, the OBH - Phono pre-amps perform miracles at a very modest price. To optimise the match with specific cartridges there are two separate products, OBH-8 for moving magnet and OBH-9 for moving coil.
Creek engineers have designed the OBH phono circuitry to use discrete transistors, instead of more usual integrated circuits. This provides the flexibility to use circuit topology more normally found in high-end equipment. A single-
ended, Class A gain stage with passive RIAA equalisation and zero negative feedback achieves tube-like performance while maintaining low noise and current consumption.
The single-ended OBH gain stage is designed in such a way that it can produce high gain and linearity, without requiring negative feedback to achieve low distortion. Zero negative feedback eliminates the need for phase compensation that would slow down the amplifier at high frequencies. Other detrimental
effects like dynamic intermodulation distortion will also be eliminated.
This allows the OBH-8/9 to produce a very open and dynamic sound. Passive EQ offers superior sonic performance to the more conventional Active EQ, but requires the careful choice of close tolerance capacitors and resistors. OBH products use 1% metal film resistors and polypropylene capacitors.
Power- on is smooth as the signal level rises slowly. Switch-off is also quiet. The performance of the OBH is only limited by the quality of its power supply and source. The OBH-8 is provided with a low cost OBH-1 power supply, whereas the
OBH-8SE and OBH-9 come with the OBH-2 power supply.
To provide a simple upgrade path for the OBH -8, it is recommended to use the high grade OBH-2 power supply.
The OBH-8 and OBH-9 use dedicated circuitry to optimise their performance and cannot be switched from MM to MC. The level output from both the OBH-8
and 9 is suitable for most line level amplifiers and the input sensitivity and loading is factory-set to suit a wide range of cartridges.
Frequency Response: 20 Hz to 20 kHz +/- 0.25 dB
SNR: -82 dB
THD: < 0.05%
RIAA Deviation: +/- 0.5 dB
Output: 250 mV
Output Impedance: 750 ohm / 220 pF
Input Sensitivity / Impedance: 3.5 mV / 47,000 ohm
Overload Margin: 22 dB operating
MM Cartridge Compatibility: 1.5 mV - 5.0 mV output
Dimensions: 100 x 100 x 65 mm
Weight: 420 g