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Sonifex DHY-04HD

Original price was: €1,890.Current price is: €1,795.

SKU: 105939
Original price was: €1,890.Current price is: €1,795.
Original price was: €1,910.Current price is: €1,810.
Original price was: €3,740.Current price is: €3,560.



Twin Digital HD Voice TBU, AES/EBU, Analogue, Ethernet, Rack Mounted

<DHY-04HD logo

The DHY-04HD HDT is a 1U rack mount twin Voice Hybrid which is used on a 3G or GSM cellular (mobile) phone network instead of a telephone (POTS) line. The DHY-04HD can accept a SIM card in the rear panel slot and by connecting a suitable GSM antenna, it can receive and make high quality broadcast calls over the cellular network, converting the 3G or GSM call to the 4 wire audio signal to and from a connected mixing console. The module used in the DHY-04HD is quad-band GSM and 5 band UMTS/HSPA+, so it can take and make calls on any 2G GSM, or 3G network.

It is ideal for studios in remote locations, for OB vans and trucks on the move, and in emergency situations where a telephone landline can’t be guaranteed, the DHY-04HD offers outstanding performance.

The DHY-04HDS has all features of the DHY-04 together with some additional front panel indicators. There are two LEDs, one for SIM enabled and one for GSM Network availability. Additionally, there is a push button which allows the mobile signal level to be displayed on the meter LEDs.

HD Voice:

HD Voice uses a coding system (also known as WB-AMR) for audio data that provides a significant enhancement to the quality of cellular phone calls. It is ideal for broadcasters and journalists, providing a frequency response up to 7kHz (twice that of a normal GSM or POTS connection).

The use of HD Voice is dependent on 3 criteria:

  1. The method has to be supported by the network, (and this may be limited by your contract), and when different networks are involved in the call, the interoperability between the networks.
  2. The actual equipment used by both ends of the call must be HD Voice compatible. Both these requirements will be established on call connection, which leads to the third criteria.
  3. The signal quality can vary during the call. Normally the hybrid will be used in a fixed location (even OB trucks are normally stationary), so the position of the antenna can be refined for best signal quality. However, the far end may be from a cellular phone, so may vary in quality and which can lead to dynamic bandwidth changes during a call. It is mostly true that network providers will only handle HD Voice on 3G networks though, in theory, it should also be compatible with enhanced 2G networks.


  • Five band UMTS/HSPA+850 / 900 / 1800 / 1900 / 2100MHz.
  • Rear panel 2G GSM or 3G SIM card insertion.
  • Ethernet web server control and configuration.
  • Front panel speed-dial buttons with redial.
  • Signal strength LED display.
  • LEDs for SIM enabled and GSM network availability.
  • Automatic operation.
  • Combined AES/EBU and analogue input and output.

Technical Specification DHY-04HDT

Audio Specification Analogue Audio I/O:

Input Impedance – Line Mode (Clean Feed): 10 kΩ balanced 0dB
Input Impedance – Conferencing: 10 kΩ balanced 0dB
Input Impedance – Microphone Mode: 2 kΩ balanced
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
Maximum Input Levels: Line +26dBu, mic -24dBu
Clean Feed Limiting Input: -4dBu for CTR21 setting, other values available, dependent on the actual country setting selected on the DHY-04HD
Output Impedance – Line Out: 50 Ω balanced floating 0dBu
Output Impedance – Conference/Record: 50 Ω balanced floating 0dBu
Output Level Gain Range: -6db, 0dB, and +6dB adjusted by 3-position front panel switch

Digital Audio I/O:

Input Impedance: 110 Ω ±20% balanced
Output Impedance: 110 Ω ±20% balanced
Sample Frequency Range: 30 – 100kHz (i.e. including 32kHz, 44.1kHz, 48kHz, 64kHz, 88.2kHz & 96kHz)
Signal Level: 2V/7V peak to peak min/max
Analogue Equivalent Level for Full Scale Digits: +18dBU
Maximum Input Level: 0dBFS, but internally limited to -6dBFS
Maximum Output Level: -6dBSFS

Cellular Connection:

Module Type: Quad-Band EGSM 850 / 900 / 1800 / 1900MHz 5-band UMTS/HSPA+ 850 / 900 / 1800 / 1900 / 2100MHz
Sensitivity: -109 dBm (typ.) @ GSM  850 / 900MHz
-110 dBm (typ.) @ DCS1800 / PCS1900MHz
-111 dBm (typ.) @ UMTS
Approvals Information: • Quad Band GSM/GPRS 850/900/1800/1900 MHz
• Output Power Class 4 (2W 33dBm) @ GSM 850/900
• Output Power Class 1 (1W 30dBm) @ GSM 1800/1900
• Output Power Class 3 (0.25W 24dBm) @ UMTS
• Output Power Class E2 (0.5W 27dBm) @ EDGE 850/900
• Output Power Class E2 (0.4W 26dBm) @ EDGE 1800/1900
• Fully Type approved conforming with R&TTE
• European – CE, GCF
• North America – FCC, PTCRB, IC
• Brazil – ANATEL
Ring Detector Sensitivity: Off, 1, 2, 3, or 4 rings

Power Supply:

Power to DHY-04HD, S & T Universal 12W power supply: 90 to 250V AC; 47-63Hz; fused 1A anti-surge fuse


Mic/Line/AES-EBU Input: XLR 3 pin female, with push-button mic/line selection
Line/AES-EBU Output: XLR 3 pin male
GSM Antenna: SMA socket
Conferencing or Record Audio: RJ45 socket
Remotes: 9-way D-type socket
Ethernet: RJ45 socket
RS232 Serial: 9-way D-type socket
Power: IEC mains (CEE22)


Accessories Order Code: Description:
DHY-04HDCON Front Panel Conversion Kit, DHY-04HDS to DHY-04HD
DHY-04HDSCON Front panel conversion kit, DHY-04HD free standing to DHY-04HDS 19” (48 cm) rack-mount front
DHY-04HDTCON Front panel conversion kit, DHY-04HD or DHY-04HDS, to DHY-04HDT 19” (48 cm) rack-mount front

Physical Specification:

Order Code:
Description: Height: Width: Depth:* Total Nett
Total Gross
DHY-04HD (Raw): Automatic digital GSM hybrid
TBU, free standing
4.5 cm
21.8 cm
17.5 cm
1.4 kg
2.2 kg
DHY-04HD  (Boxed): 6 cm
34 cm
27 cm
DHY-04HDS (Raw): Automatic digital GSM hybrid
TBU, rack mounted
4.5 cm (1U)
1.8” (1U)
48.3 cm
(19” rack width)
17.5 cm
1.45 kg
2.3 kg
DHY-04HDS (Boxed): 6.8 cm
58.8 cm
27 cm
DHY-04HDT (Raw): Twin automatic digital
GSM hybrid TBU, rack
4.5 cm (1U)
1.8” (1U)
48.3 cm
(19” rack width)
17.5 cm
2.80 kg
4.4 kg
DHY-04HDT (Boxed) 6.8 cm
58.8 cm
27 cm
*Depth is measured from the front to the end of the connectors fitted to the back of the unit.