DH20 / DH22 / DH30 Digital Hybrids

Single and dual-line digital telephone hybrids

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DH20 / 22 Overview

Are you looking for the very best, most affordable digital telephone hybrid available? You just found it. The DH20 and DH22 Digital Hybrids incorporate the latest in DSP technology to provide you with the best sound and easiest installation.

The DH20 and DH22 are high quality single-line and dual-line telephone interfaces, designed to interconnect a standard telephone line and your audio equipment, allowing you the ability to send audio to and receive audio from a connected telephone line. The DH20 and DH22 are ideal when the very best audio quality is required for talk shows, news feeds, production, recording studios, and internet applications.

Our newest DSP technology delivers better and more reliable sound quality. The DH20 and DH22 deliver the deepest and most stable hybrid null, ensuring maximum isolation between the send and caller audio. That means no echo and no "bottom of the barrel" sound.

In addition, we've added selectable automatic gain control (AGC) and caller ducking. With AGC, each call will be delivered to your equipment at the same level. Caller ducking reduces the caller's audio level when the announcer speaks, providing a more "controlled" environment. We've also added a speaker amplifier so you can connect a speaker directly to the unit and monitor callers without headphones.

DH20 / 22 Features

  • The world's best, most affordable digital hybrid
  • DSP digital technology ensures the very best audio quality and the deepest, most reliable hybrid null
  • Easy to install, simple to operate
  • Built-in speaker amplifier
  • Balanced audio in and out
  • Mic or line input
  • Selectable AGC ensures every caller is at the same audio level
  • Selectable caller ducking
  • Selectable auto-answer/auto-disconnect compatible with most telephone central offices including loop current interruption and busy/reorder tones
  • Remote control and status
  • Automatically accepts all worldwide voltages
  • Worldwide compliant, including FCC, CSA, CE and CTR21
  • Dry line capability (U.S. version only)

DH20 / DH22 Specifications

Connections

  • Caller Output: XLR male, 0dBu nominal, adjustable, balanced, 50 Ohm impedance
  • Aux Output: XLR male, 0dBu nominal, adjustable, balanced, 50 Ohm impedance
  • Telco Line: RJ-11 connector, POTS line or analog extension from a PBX or dry line (no DC offset voltage)
  • Telco Set: RJ-11 connector
  • Remote: DB-25 Female
  • Remote Send Input: 0dBu nominal, adjustable, unbalanced, 20k Ohm impedance
  • Remote Caller and Aux Output: 0dBu nominal, adjustable, unbalanced, 50 Ohm impedance
  • Control Inputs: Remotely activate any of the following functions with a switch closure to ground: On, Off, and Monitor Mute
  • Status Outputs: Remotely check the status of the hybrid using the On and Off status outputs. Status outputs are open collector outputs rated at 30VDC and 40mA maximum
  • Monitor Output: 1/4" stereo jack: Tip=+phase, Ring=ground, Sleeve=ground, 1W output into an 8 Ohm load
  • Send Input: XLR female, Mic/Line selectable, -55/0 dBu nominal, adjustable, balanced, bridging, 20k Ohm impedance

Telephone Transmit

  • Nominal send input of 0 dBu referenced to -15 dBu onto the telephone line
  • Frequency Response: 250 Hz to 3.5 kHz, ±1dB
  • Distortion: <0.1%

Telephone Receive

  • Nominal telephone line level of -15 dBu referenced to caller output of 0 dBu
  • Frequency Response: 250 Hz to 3.5 kHz, ±1 dB
  • Distortion: <0.1%

Mix-Minus

  • Caller-to-Send separation: 50 dB nominal
  • Tail time: 32 milliseconds

 

Controls

  • On/Off Buttons
  • Volume Up/Down Buttons

Status LEDs

  • On Status, Off Status
  • Send Audio Presence
  • Caller Audio Presence

Adjustments

  • Send Input Level
  • Caller Output Level
  • Auxiliary Input Level
  • Auxiliary Output Level
  • Burst Adapt Select
  • Mic/Line Select
  • Caller Boost Select
  • Momentary/Latching Select
  • Auto Answer/Disconnect Select
  • Caller Control Select (0, 6, 12, or 18 dB)
  • AGC Select
  • Auto Mix-Minus Select
  • Aux Mix Select

Null

  • Send-to-Caller separation: 55dB nominal
  • Tail time: 32 milliseconds

Power & Physical

  • Power: IEC Type, Auto Adjusting 100-240VAC, 2A, 50/60Hz, 30W
  • Size: 17.125" L x 10.125" D x 1.75" H (43.6 cm x 25.7 cm x 4.44 cm)
  • Weight: 6.35 lbs (2.88 kg)
  • Operating Temperature: 32-100° F (0-38° C)
  • Humidity: 0-80 percent
Hybrids

DH30 Overview

With the variety of phone systems in the world today, it is becoming increasingly difficult to have all callers sound the same on-air. To help bring uniformity and high quality sound to a broadcast talk show environment, we have created the DH30. The DH30 provides a high quality interface between a standard telephone line and your audio equipment.

Designed with both AES/EBU and analog inputs and outputs, the DH30 can interface with the latest digital and analog consoles. To ensure quality sound in studios that have open speakers and microphones, the DH30 was created with an acoustic echo cancellation feature.

The DH30's digital signal processing (DSP) has multiple adjustable parameters to provide you with the best send and caller audio signals. New audio processing features such as the compressor and downward expander functions ensure that the best audio reaches your audience. All audio processing features are programmable via the front panel controls. For the deepest, most reliable hybrid null, and the best quality caller audio for your application, the DH30 is the answer.

Easy to use and install, the DH30 has simple front panel controls and remote control capability. These controls put the On, Off, Rec, and Cue functions right at your fingertips. The DH30 also includes a 2W monitor amp with volume controls right on the front panel. The Rec function sends a start/stop signal to your external recording device. The Cue function allows you to control which audio signal should be sent to the caller, allowing you to switch from the Send input to the Cue input at the touch of a button.

DH30 Features

  • Remote controllable presets
  • Password protected
  • 24-bit digital signal processing (DSP)
  • AES/EBU digital or analog audio input and output
  • Record and Cue functions
  • Selectable auto mix-minus
  • Selectable acoustic echo cancellation
  • Selectable auto answer and disconnect
  • Integrated monitor amp with front-panel volume control
  • Remote control via contact closures or RS-232
  • Adjustable caller control (ducking)
  • Adjustable three-band equalizer
  • Adjustable compressor and expander
  • Bass boost
  • Microphone send and cue preamps
  • Automatically accepts all worldwide voltages
  • Three selectable presets for customized audio
  • Worldwide compliant including FCC, CSA, CE, CTR 21

DH30 Specifications

Connections

  • Cue In: XLR Female, Mic/Line selectable, -55 or 0 dBu nominal, adjustable, balanced bridging, 20k Ohm impedance, selectable 12VDC phantom power
  • Caller Output: XLR male 0dBu nominal, adjustable, balanced, 50 Ohm impedance
  • Aux Output: XLR male 0dBu nominal, adjustable, balanced, 50 Ohm impedance
  • Telco Line: RJ-11 connector - POTS line or analog extension from a PBX or dry line (no DC offset voltage), A-Lead supervision provided
  • Telco Set: RJ-11 connector, A-Lead supervision provided
  • Remote: DB-25 Female
  • Remote Send Input: 0dBu nominal, adjustable, unbalanced, 20k Ohm impedance
  • Remote Caller and Aux Output: 0dBu nominal, adjustable unbalanced, 50 Ohm impedance
  • Control Inputs: Remotely activate any of the following functions with a simple switch closure to ground: On, Off, Cue, and Rec along with preset selection controls 1,2, and 3 or with Send, Caller, and Monitor Mute controls
  • Status Outputs: Remotely check the status of the hybrid using the On and Off status outputs. Status outputs are open collector outputs rated at 30VDC and 40mA maximum
  • Monitor Output: 1/4" stereo jack Tip=+phase, Ring=ground, Sleeve=ground, 1W output into an 8 Ohm load
  • Send Input: XLR female Mic/Line selectable, -55/0 dBu nominal, adjustable, balanced, bridging, 20k Ohm impedance
  • AES/EBU In: XLR, Pin 1=ground, Pin 2=+phase, Pin 3=-phase; 32, 44.1, or 48 kHz sample rate
  • AES/EBU Out: XLR, Pin 1=ground, Pin 2=+phase, Pin 3=-phase; 32, 44.1, or 48 kHz sample rate
  • RS-232: DB9 Female Connector, 9,600 baud rate, used for status and control via a PC or other RS-232 controller
  • Record Control: DB9 Female, Start, stop, and enable outputs are open collector outputs rated at 40VDC and 50mA maximum

Controls

  • LCD programming display, ENTER/ESC/st programming buttons, Monitor volume control, Send-level LED bar meter, Caller-level LED bar meter, Record, cue, Hybrid On/Off, Buttons with status LEDs

 

Telephone Transmit

  • All measurements referenced at -15 dBm level on the phone line
  • Frequency response: 250 Hz to 3.5 kHz, ±1 dB
  • SNR: >70 dB
  • Distortion: <0.15%

Telephone Receive

  • All measurements referenced at -15 dBm level on the phone line with caller processing options bypassed
  • Frequency response: 250 Hz to 3.5 kHz, ±1 dB
  • SNR: >70 dB
  • Distortion: <0.1%

Echo Cancellation/Mix-Minus

  • Tail time: 120 milliseconds
  • Null: 50 dB

Telco Cancellation

  • Tail time: 32 milliseconds
  • Null: 55 dB

Null

  • Send-to-Caller separation: 55 dB nominal
  • Tail time: 32 milliseconds

Power & Physical

  • Power: IEC Type, Auto Adjusting 100-240VAC, 2A, 50/60 Hz, 30W
  • Dimensions: 17.125" L x 10.125" D x 1.75" H (43.5 cm x 25.7 cm x 4.44 cm
  • Weight: 6.7 lbs (3.04 kg)
  • Operating Temperature: 32-100° F (0-38° C)
  • Operating Humidity: 0-80 percent
Hybrids