Biquad HELLO 1

Biquad HELLO 1 – One-Line Hybrid Telephone Interface

The Biquad HELLO 1 is a one-line hybrid telephone interface designed to meet the standard rack specifications, making it an excellent choice for use in radio and TV studios. This physical telephone interface is analog and passive, featuring an identical circuit to all other ALO models. Notably, it does not require an external power supply, ensuring user-friendliness.

This interface incorporates RFI (Radio-Frequency Interference) filters on both the telephone line input and the audio inputs and outputs to prevent electromagnetic interference. Additionally, it boasts protection against electric discharges from the telephone line, safeguarding your equipment. It is compatible with conventional telephone lines and PBX extensions, supporting voltage variations between 20 and 50V, with a minimum current requirement of 20mA.

Equipped with balanced audio inputs and outputs featuring XLR connectors, the interface uses transformers for isolation, guaranteeing high audio quality and immunity to noise, resulting in a clear and pristine sound. The audio gain control is conveniently located on the rear panel for easy adjustments.

The hybrid circuit responsible for transforming 2-wire to 4-wire signals is fully electronic and active, offering an echo cancellation adjustment that provides up to 50dB of isolation at 1KHz.

The front panel of the equipment includes an ON/OFF switch for handling phone calls, as well as a call indicator LED that remains illuminated when the equipment is in use. Additionally, there are volume controls for both the listener’s return audio and a separate audio output for the mixing console.

The ALO 1 is a highly versatile solution, ideal for use in transmission and recording studios to extract or insert high-quality audio on conventional telephone lines (POTS). Its case features a premium finish with a brushed stainless steel panel, ensuring a sleek and professional appearance.