Octave HP 700 SE Vacuum Tube Preamplifier

PSU Technology

In combination with the newly developed high-precision, low-noise supply-voltage stabilizing circuitry, the separate power supply unit for the HP 700 SE ensures constancy of the audio output even when the mains voltage is subject to wide fluctuations and high interference levels. Added to this, the integrated control logic system guarantees maximum operational reliability and, backed by our exclusive soft-start technologies, ensures the valves and the unit have a life of up to twenty years.

Bypass

The multi-channel bypass function allows the HP 700 SE to be integrated into an existing home-theater combination. The logic-controlled input selector circuitry allows selection of the bypass function for an XLR or phono input on the rear panel. The HT signal is present at all three outputs.

External Power Supply Unit

The sophisticated design of the HP 700 SE makes extremely high demands on the power supply unit. The external power supply unit is magnetically screened and supplies a clean voltage to the HP 700 SE. The screening is also essential to ensure low- noise, low-hum operation of the phono MC input.

Additional Individualization options

The connection possibilities of the generously configured standard model are rounded off by two user-selectable optional input modules. An optimized input module can be used for unusual applications, for anything from an MC step-up transformer to a transformer-based XLR input module. The plug and play modules can be readily installed or upgraded at any time.

Phono

Next-step technology has also been applied in the redesign of the Phono RIAA amplifier. The further development of the RIAA stage has improved the signal/noise ratio, while simultaneously reducing system-related distortion. The widening of the bandwidth enables accurate RIAA equalization and exploits the full potential of analog reproduction. The wide variety of optional input modules ensures that the optimal input can be installed for every pickup.

Tone control precision tone control

The innovative optional tone control rounds off the HP 700 SE equipment. The precision valve-based tone control unit guarantees consistency of the sound, even at low volume. Precision adjustment of bass and treble, with a 0.3dB channel separation, allows the tone to be adjusted without impairing the spatial reproduction.

Balance control

The frequency-compensated balance control allows channel-separated volume adjustment in 1 dB steps. This technology eliminates any controller-related sound shifts. Using 12-position stepped switches, the setting is longtime stable, with 100% repeatability.

Output selector switch

The unit output can be switched to several zones by manual activation of the outputs. Whether the output is through XLR, phono or all three outputs simultaneously, a total of three output stages can be utilized for separate rooms, different speakers or bi and tri-amping.

Stepped volume control

The optional, frequency-compensated 47-position stepped switch ends the debate about the influence of the controller on the quality of the music signal. At 0.1dB, the channel deviation is supreme. Our own in-house development, the volume control design maintains the frequency bandwidth constant throughout the entire control range, reducing controller-related distortion to a scarcely measurable level.

However, as a result of the mechanical design of the stepped attenuator, the switch positions cannot be controlled using the remote control.