Plantronics (now known as "Poly" after their merger with Polycom) has a well-deserved reputation for manufacturing top of the line headsets. Their wireless headsets, including the Savi 700 series, the CS500 series, the MSA200 series, and the Voyager Legend series, are all equipped with EHS (Electronic Hook Switch) capability. If you have a phone that is compatible with EHS, this means that you can answer calls by tapping your headset. If your phone doesn't support EHS, then you are forced to use the old-school (but effective) mechanical lifting apparatus that Plantronics sells as an accessory. This device attaches to your phone and physically lifts it off the hookswitch when you tap the button on the headset. EHS eliminates the need for the lifter.
Grandstream's GXP 21xx line of IP phones support the Plantronics EHS headsets - but you have to have the correct adapters to make it work (The complete Grandstream headset compatibility guide is attached here for reference).
The Plantronics Adapter you need is model APD-80, readily available from any distributor or retailer that carries Plantronics at a price of about $50. But you also need a second adapter - a fact that is not easy to spot in Plantronics documentation (though Grandstream's does) That is the Plantronics M12 Cable Adapter, also known as part number 85638-01. That adapter is not as easy to come by - in fact, Plantronics' own website doesn't list it anyplace. Teledynamics carries it, as do some other distributors, at a price of about $12.
If you connect everything up with just the APD-80 cable, you won't get the EHS function to work. As it turns out, the RJ9 connector on that adapter cable - the plug that connects to the headset jack on the phone - puts the conductor that carries the signalling voltage on the opposite side of the connector than where Grandstream has it wired in their phone's headset jack. According to some forum posts I found, you can doctor the APD-80 by flipping it over and crimping a new connector onto it. Or, you can spend the extra $12 plus shipping for the M-12/85638-01.
Even the Grandstream literature is not clear on what the M-12 is used for. It makes it seem like it is only needed so that you can extend the headset connection to accommodate the fact that some of the Grandstream phones have their headset jack on the side instead of on the back. But even on a GXP-2170, which does have the headset jack on the back of the phone, you still need to have the M-12 adapter - or you need to "fix" the APD-80.
Follow these instructions (provided by Plantronics) - Except don't connect the plug to the phone. Connect it to the M-12 adapter, then connect the adapter to the phone:
- Phones require firmware 184.108.40.206 or higher
- Select the APD-80 EHS by going to Menu > Config > Headset Type > Plantronics EHS
- Use a Part Number 85638-01 adapter (sold separately through our distributors) to extend the ADP-80 audio input to reach the headset jack on the phone.
To Install the EHS Cable
- On your base, set your compatibility switch and speaking and listening volumes to the following:
|Setting||CS500 Series/Savi 700 Series|
| ||Image of Settings|
- Connect your EHS cable to your phone as follows: