Is the Polycom Duo a phone or an accessory?

An accessory. It's a wired expansion microphone that plugs into a SoundStation IP 7000 (or older Polycom HDX video conferencing system) to extend microphone pickup down a long table. It doesn't register as a SIP endpoint.

What does the Polycom Duo work with?

Primarily the SoundStation IP 7000 — the only SoundStation in the family with expansion mic ports. Also compatible with older Polycom HDX-series video systems. Doesn't work with the IP 5000 or IP 6000.

Is the Polycom Duo still made?

No — discontinued alongside the SoundStation IP family in 2018. Our stock is refurbished/pre-owned. For new deployments, the Poly Trio 8800 with its modern satellite microphone accessories is the equivalent.

Will voip.army provision the Duo?

There's no provisioning required — the Duo is a hardware accessory that auto-detects when plugged into a SoundStation IP 7000. As long as the IP 7000 itself is onboarded on our legacy provisioning network, the Duo just works.

Polycom · expansion microphone

Polycom DuoStill works. Still supported.

The Polycom Duo is a wired expansion microphone accessory for SoundStation IP conference phones — extends the pickup range of an IP 7000 (or compatible Polycom HDX video conferencing system) down a long boardroom table. Sold individually or in pairs.

Display

expansion accessory

SIP accounts

Accessory

Ethernet

Dual 10/100

Type

Expansion microphone (SoundSta

EOL year

2018

Condition

Refurbished / pre-owned

$89 refurbished

or rent for $7.99/mo — month-to-month, return anytime

Pre-owned, tested, re-flashed for voip.army — 30-day return

Order a Polycom Duo Rent for $7.99/mo Datasheet (PDF) ↓

✓ Auto-provisioned out of the box ✓ Warranty replacement included with rental ✓ 30-day return on refurbished

Polycom Duo VoIP phone — front view with handset and dialpad — Polycom Duo

Why we still support the Polycom Duo.

The Polycom Duo (also marketed at times as the Polycom HDX/IP 7000 Expansion Mic) is an accessory, not a standalone phone. It's a wired satellite microphone that plugs into the back of a SoundStation IP 7000 or compatible HDX video system to extend the chassis's pickup range further down a long table.

A SoundStation IP 7000 alone picks up roughly 20 feet from the unit. Add two Duo expansion mics (one at each end of a long boardroom table) and you cover 40-plus feet with no pickup dead zones. Each Duo has its own LED status ring and mute button, so participants near it can mute locally without reaching for the central chassis.

For existing IP 7000 deployments, the Duo is a drop-in capacity extension — no configuration needed, it auto-discovers on the IP 7000's expansion bus. For new conference rooms the modern equivalent is the Poly Trio 8800 with its compatible satellite microphones.

Full technical specifications.

Display & user interface
Display	No display — expansion microphone accessory
Line keys	Accessory — no line keys
Soft keys	—
VoIP & SIP
SIP accounts	Accessory (no SIP)
SIP protocols	Not applicable — passive accessory
Codecs	Wideband audio passthrough
Audio
Speaker	Full-duplex with Polycom Acoustic Clarity
HD voice	Narrowband only (G.711)
Headset	Speakerphone only / not applicable
Connectivity
Ethernet	Dual 10/100 Mbps
PoE	IEEE 802.3af Class 2
Power & physical
Power source	PoE 802.3af Class 2 (preferred) or Polycom power adapter (sold separately)
Weight	0.30 kg
Dimensions	157 × 117 × 28 mm
Wall-mountable	Not applicable
Lifecycle status
EOL year	2018
Firmware on voip.army	Polycom UCS 4.0.15 (legacy provisioning VLAN)
voip.army stock	Refurbished / pre-owned, tested and re-flashed

How it works on voip.army.

The Polycom Duo runs Polycom UCS firmware 4.0.15 — the last release that supports this hardware. It onboards onto voip.army the same way as any current phone, just on our legacy provisioning VLAN because the phone's TLS stack predates modern web standards. Call quality is normal SRTP.

60s

Time from plug-in to first call

Boot, fetch config from our provisioning server, register, ready. About one minute on a normal internet connection.

SIP accounts on one phone

Run up to 0 simultaneous SIP registrations. Each line key has a dual-color LED for status.

Per-device onboarding fees

Bringing your own? Send us the MAC, factory-reset, plug in. No charge to add it to the fleet.

4.0.15

UCS firmware version

Last firmware Polycom shipped for this phone (2018). Still works perfectly on voip.army; provisions over our isolated legacy VLAN because the phone can't speak TLS 1.2.

100m

Ethernet to the workstation

PC pass-through port on the back lets you daisy-chain a single ethernet drop to phone and computer.

802.3af

PoE class

Class 2. Any 802.3af-compliant switch from the last 15 years will power it without issue.

Onboarding a fleet of Polycom Duos?

Send us a CSV of MAC addresses. We add them to the provisioning server, you factory-reset and plug in, they pick up their voip.army config within a minute.

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