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Sonifex DHY-03S - Automatic Digital TBU, Rack Mounted

by Sonifex
£1,337.94 inc. vat
£1,114.95 ex. vat
Please contact us for availability.

Sonifex DHY-03S

The Sonifex DHY-03S is a single automatic digital TBU, 19" (48.3cm) rack-mount unit.. The digital Sonifex DHY-03 telephone hybrid is probably the best performing digital hybrid in the world, with simply stunning line balance rejection figures. For the best sounding audio calls you’re likely to hear, you should specify the DHY-03.

Sonifex DHY-03 Features

  • Fully automatic - adapts to varying line conditions and has automatic signal limiting.
  • Fully adaptive echo cancellation to 127msec - default is 24msec.
  • 76dB typical line balance rejection offering superb performance and crystal clear audio.
  • Front panel input and output gain controls.
  • Front panel LED metering of receive and send signals.
  • Built-in conferencing for 2 hybrids, so that a single telco channel on a mixing desk can receive 2 calls.
  • Integrated ring detector - automatic call answering after a pre-determined number of rings.
  • Automatic call disconnection. Fitted with K-break, line polarity reversal and dial tone disconnect detection, defined by the country selection.
  • Automatic ducking facility allows the talent to ‘shout-down’, or talk over, a caller by reducing the gain of the caller’s signal if it goes above a certain level.
  • Local and remote line hold switching - calls can be remotely switched through a mixing console.
  • Line hold/release button to control line hold circuit, illuminates to indicate the status of the line and flashes to show ring status.
  • DTMF tone recognition allowing a opto-isolated GPI output to be made on receipt of selected DTMF tones, e.g. for starting a studio automation recorder automatically to record a remote telephone interview.
  • International operation with built-in configurable settings for each country. Country selection allows the unit to provide line impedance and a simulation circuit to match the country.
  • RS232 serial port for remote control of the TBU, DTMF tone dialling and firmware upgrades to add new country settings.
  • Remote port distributes the remote line connect switch and tally output, a momentary/latch selector and the DTMF detect output.
  • The remote line connect switch can be either momentary or latching in its action.
  • Balanced mic/line input - 10k balanced input selectable for 0dBu clean feed line, or microphone level with adjustable gain.
  • Balanced output - 0dBu low impedance balanced output, with output gain settings.
  • Record output - the conferencing output can be set via a jumper to give a mix of the caller and mic/line input signals for recording both sides of the telephone conversation.
  • Line limiter, bandpass filter and output noise gate with preset threshold providing low distortion audio.
  • Built in universal power supply between 90V AC and 250V AC, 47-63Hz, IEC mains input.
  • ETSI approval compliant with European PTT specifications.

Sonifex DHY-03 Specifications

Audio Specification

  • Input Impedance - Line Mode (Clean Feed): 10kΩ balanced 0dB
  • Input Impedance - Conferencing: 10kΩ balanced 0dB (not for DHY-03EC)
  • Input Impedance - Microphone Mode: 2kΩ balanced (not for DHY-03EC)
  • Input Level Gain Range: +6dB, 0dB, and -6dB adjusted by 3-position front panel switch, +10dB jumper
  • Microphone Level Gain Preset: From 65dB to 35dB (not for DHY-03EC)
  • Maximum Input Levels: Line +26dBu, mic -24dBu
  • Clean Feed Limiting Input: -4dBu for CTR21 setting, other values available *
  • Bandwidth to Telephone Line: 250Hz - 4kHz, -3dB ref 1kHz
  • Telephone Line Impedance: 600Ω, 900Ω plus 14 other complex impedance circuits *
  • Output Impedance - Line Out: 50Ω balanced floating 0dBu
  • Output Impedance - Conference/Record: 50Ω balanced floating 0dBu
  • Output Level Gain Range: +6db, 0dB, and -6dB adjusted by 3-position front panel switch
  • Rejection Ratio: 76dB on tones or complex waveforms, reference peak level of 0dB
  • Ring Detector Sensitivity: Off, 2, 4 or 6 rings
  • Power to DHY-03, S & T: Universal 12Ω power supply: 90 to 250V AC; 47-63Hz; fused 1A
  • Power to DHY-03EC: ±15 V DC @ 160mA per rail or regulated +5V DC @ 600mA

* These values are dependent on the actual country setting selected on the DHY-03


  • Mic/Line Input: XLR 3 pin female, with push-button mic/line selection
  • Line Output: XLR 3 pin male
  • Telephone Line: RJ11 6/4 socket
  • Telephone Handset/Instrument: RJ11 6/4 socket
  • Conferencing or Record Audio: RJ45 socket
  • Remotes: 9-way D-type socket
  • RS232 Serial: 9-way D-type socket
  • Power: IEC mains (CEE22)
  • Connections for Eurocard: 64 pin DIN 41612 male (plug)

Each DHY-03, S & T unit is supplied with 1 x RJ11 to RJ11 telephone line lead, 1 x RJ11 to BT plug telephone line lead, 1 x BT handset socket to RJ11 plug adapter, IEC mains lead fitted with moulded mains plug, handbook and warranty card.