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EHS means Electronic Hook Switch and is a feature that allows wireless headsets to accept and end calls directly by pressing a specific button. In other words, apart from the pure speech transmission, EHS makes call acceptance possible directly at the headset. By using EHS, telephones and headsets of different manufacturers can be combined. The Snom EHS solution supports both wireless headsets from GN Netcom/Jabra as well as devices from Plantronics. This requires a corresponding connector at the headset.

The Snom EHS solutions consist of an EHS adapter box and necessary cables.



NOTE: A third party accessory is available from Sennheiser, the splitter cable connects the headset's base station to a desktop telephone and the Snom EHS box.

More information regarding the Sennheiser CEHS-SP 01 can be found here.

If you want to know which headsets have been tested for compatibility with Snom Desk Phones, please have a look at the following list: Compatible Headsets

But this is not a guarantee that this headset will work perfectly with the Snom EHS adapter.

Attention: Never forget, you have to restart your Snom Desk Phone after connect the Headset with a EHS Adapter to get the Headset working.

Supported Phone Series

Following series/phones currently supporting EHS Advanced:

  • Snom 3xx series (Snom 300 with MAC addresses 00041328xxxx and higher)
  • Snom 7xx: FW and higher
  • Snom 8xx series
  • Snom D3xx series
  • Snom D7xx series


Cables are supplied with the Snom EHS Advanced.

The connection of wireless headsets, with a transmitter/charger station connected by cable to the desk phone, from third party suppliers (Jabra, Plantronics, Sennheiser) is not always done in the same way. At the moment, there are typically 3 different cases.

  1. Case 1 (default)
    Some are connected completely via the Snom EHS Advanced adapter, such as the Plantronics Savi 740, which is connected to the EHS adapter using the 3.5 jack plug (audio) provided with the EHS adapter and then connected to the EHS input of the phone using the cable shown in picture A (see below) and to the headset jack of the phone using the cable provided with the headset. This is the standard case.

  2. Case 2
    Some headsets have two outputs, such as the Jabra Pro 9470, which has an output (RJ45) to the EHS, to which the EHS adapter is connected (next to the jack input) using the cable supplied with the EHS (in the example RJ45/RJ45 - Figure E) and then the connection is made to the EHS input of the phone using the cable supplied with the EHS adapter, picture B with RJ45/RJ12.

  3. Case 3
    There are also cases in which an EHS adapter is already included as with the Sennheiser DW Pro 1, in which no additional EHS adapter from Snom is required. (The CEHS-CI 02 cable from Sennheiser should fit here).

Please note that the EHS connection on our phones has changed over time. Older models of the D7xx series (D710, D712, D715, D725, D745, D765) have a 4-pin flat connector, and you need the cable shown in picture D.

Newer devices have an RJ12 Western plug as shown in picture A. Here only the labeling has changed from EXT to EHS over time. The EHS input is mostly hidden behind a black square protection cap.


  • RJ12 cord (Mod 6/6).
    Snom 320, Snom 370 & D375: Connecting the port labeled EXT and the Snom EHS Advanced.
    Snom 300: Connecting the port labeled I/O and the Snom EHS Advanced.
    NOTE: This is the standard for Snom Desk phones: D305, D315, D335, D345, D375, D385, D717, D735, D785.

  • RJ45-RJ12 cord (Mod 8/6. For the connection between the port labeled EHS on the Snom 870/ Snom 821 phones and the Snom EHS Advanced.

  • Y-cord: If you are using a 3xx expansion module as well as the Snom EHS Advanced, plug the RJ12 connector labeled "Telephone" into the EXT port on the Snom 320/370 phone. Connect the RJ12 connector labeled "EHS box" to the Snom EHS Advanced; connect the RJ12 connector labeled "Extension panel" to the expansion module.

    NOTE: EHS with hardware revision R3A/B is no longer compatible with the Y-cord! For this reason, the Y-cord is no longer delivered with EHS revision R3A/B.

  • Cable with proprietary Snom plug (labelled 7xx) to RJ12 plug (labelled EHS box) cable: For the connection between the proprietary Snom port on Snom 7xx and the Snom EHS Advanced.

    NOTE: The cable is included in boxes labelled "Snom EHS Advanced V2.0". If you have an older version (i.e., if there is no version number on the box) you can order the cable separately - see below.
    NOTE: This is the standard for Snom Deskphones: D710, D712, D715, D725, D745, D765.

  • RJ45 cord (Mod 8/8): For the connection between the Snom EHS Advanced and the "Jabra" Wireless headset (AUX port).

  • 3.5 mm Stereo Jack: For the connection between the Snom EHS Advanced and a "Plantronics" Wireless headset (accessory port).

Download EHS - Quick Installation Guide here:

Available separately


  • Proprietary Snom connector-RJ12 cable: For the connection between the proprietary Snom port on 7xx and D7xx phones and the Snom EHS Advanced.
    NOTE: The cable is included in boxes labeled "Snom EHS Advanced V2.0". You need to order the cable (PN 0003383) separately only if you have an older version of the Snom EHS Advanced (i.e., if there is no version number on the box).
    NOTE: The footstand of the 7xx needs to be removed for connecting the cable. Look at the illustration in the Quick Installation Guide Snom EHS Advanced prior to plugging in the connector to make sure that you do it correctly.

Supplied with the headset

The 4P4C audio cable is NOT supplied with the EHS Advanced. It comes with the headset base station and is connected to the headset port on the Snom phone.


Jabra &  Plantronics

For the list of tested and approved Jabra & Plantronics headsets, please visit our dedicated page .


  • Foot stand needs to be removed temporarily for connecting the cable.
  • Please make sure to connect the cable as shown in the picture list below.
Current Snom phones D3xx / D7xxOlder Snom phones

Snom phone + "Jabra" Headset

Snom phone + "Plantronics" Headset


  • To shift between RHL/DHSG/AEI (different EHS modes) make sure that the headset is placed in the base during this operation.
  • Please set the operating mode to “DHSG” (if available).

Difference between standard interface and extended interface
Limitations of the standard headset interface:

  • Headsets with the standard interface (like, for example, the GN9350) only listen for one command, and that is incoming call indication. It is not possible to control the headset from the phone and turn it on or off.
  • To do that, you need a headset with the extended interface like, for example, the GN9350e.
  • The Snom EHS Advanced supports both the standard and extended interface.

(1) Not included in delivery