Octave Audio HP700 SE

The Octave HP 700 SE tube preamplifier follows on from the HP 500 model, introduced in 1986, whose basic circuit served as the starting point for thirty years of uninterrupted development. This technical lineage, combining refined tube design with a modular architecture, had already earned the HP 700 international recognition thanks to its capacity for evolution. The SE version goes further by combining new precision technology with sonic refinements to the output stage. The modular logic is retained: it allows each listener to adjust the unit to their needs rather than being subject to fixed characteristics.

In terms of connections, the rear panel of the HP 700 SE differs from its predecessor by the addition of two XLR sockets arranged in parallel with the two RCA outputs, allowing for all bi-amplification configurations. The most notable development, however, concerns the class A output stage, reworked following lengthy and extensive measurements, complemented by listening sessions, with the aim of further refining the sound reproduction, the midrange register in particular benefiting from these adjustments. The set of tubes remains identical to that of the HP 700, as does the full range of other technical refinements that have made this preamplifier's reputation.

The "precision technology" is based on a tube circuit offering an extended bandwidth up to 1 MHz, an output resistance of just 100 ohms and a distortion rate of 0.001%. Three gain levels, combined with a selectable output impedance, allow the unit to be precisely matched to the characteristics of the rest of the chain, particularly to align the volume setting with the efficiency of the speakers used.

The unit also incorporates a new supply voltage stabilisation circuit, designed for low noise levels and high precision. Combined with an external power supply unit with magnetic shielding, a key element in limiting noise and hum at the MC input, it ensures the stability of the audio signal even in the event of significant mains fluctuations or major interference. An integrated control logic system also ensures high operating reliability and, thanks to the brand's own soft-start feature, contributes to a lifespan of the tubes and the unit of up to twenty years.