March 28, 2011


Clear-Com 2-channel stations have 6-pin XLR connectors to connect to the intercom line. These systems use a female 4- or 5-pin XLR connector on the headsets and a male 4- or 5-pin XLR connector on the user stations.

The pin out of the headset connectors is as follows:

4-pin XLR:
  • Pin 1 - Microphone common
  • Pin 2 - Microphone "hot"
  • Pin 3 - Headphone common
  • Pin 4 - Headphone "hot"
5-pin XLR:
  • Pin 1 - Microphone common
  • Pin 2 - Microphone "hot"
  • Pin 3 - Headphone common
  • Pin 4 - Left Headphone "hot"
  • Pin 5 - Right Headphone "hot"

March 27, 2011

Application Notes #1102

APPLICATION: A corporate campus needs wireless intercom in 5 seperate locations for production, event and maintenance staff, along with IFB for talent/presenters in the studio and two auditoriums. All five locations must link to a central Master Control room.

PRODUCT MUST: The wireless must work in congested UHF and Wi-Fi environment in a building that is shielded. The Director/TD in the central Master Control must be able to give direction to talent in three of the locations. The Director/TD must be able to switch between locations and/or tie them together instantly.

SOLUTION: Clear-Com's Tempest Digital Wireless Intercom in the five locations and a PiCo 36-port matrix frame with V-Series Panels (user stations).
Several locations had 4-5 wireless users, others had fewer users. Three IFB's were needed at two of the locations. A fiber backbone was used to connect remote locations to the Master Control.

March 25, 2011

ProLight+Sound Expo 2011

Come visit Clear-Com!

Frankfurt, Germany
Hall 8, Stand L71

This year, we will be demonstrating the widest range of wireless intercom solutions, intelligent TDM Matrix and Intercom-over-IP network solutions and more! Don't have a ticket to Prolight+Sound? Click here to pre-register today!

March 18, 2011

Partyline Components

Partyline intercom systems are frequently referred to as 2-wire. This term can be misleading since the stations are connected together using 2-conductor shielded microphone cable and the shield is a conductor. This connection is typically used to carry the partyline voice on one wire and the station operating power on another wire.

The interconnecting cable for most intercoms is standard microphone cable with 3-pin XLR type connectors. In any system, pin 1 and the shell of the XLR connector should NOT be connected together. Clear-Com's 2-wire Partyline system (Clear-Com Encore) uses a single audio pair to connect user stations to an intercom master station/power supply via daisy-chain wiring. Splitter boxes can also be used to expand the system.

The power supply generates DC power for the entire system. The power supply usually includes the system termination.

Clear-Com's Encore Partyline systems are the distributed amplifier kind, allowing each user to adjust their own listening level. The distributed amplifier is built into the user station. The user connects to the user station via a headset or loudspeaker and microphone or some combination.

Each main and remote station contains its own mic preamplifier, headset or speaker power amplifier, volume control(s), talk switch(es) and signaling circuitry. Stations bridge the intercom line at a very high impedance and place a minimum load on the line. The audio level remains constant and does not fluctuate as stations leave and join the network. Some user stations have "loop-thru" connectors that allow "daisy-chaining" stations using a single connection to the power supply.

March 15, 2011

Application Notes #1101

APPLICATION: How do 40 wireless intercom users work in congested RF environments and tour the world?

PRODUCT MUST: Work in congested UHF and Wi-Fi environments, be easy to manage, interface easily with wired intercom, support large numbers of users, be easy to set up, and be extremely dependable.

SOLUTION: Clear-Com's Tempest Digital Wireless System
Tempest Digital Wireless can support large numbers of wireless users, AND free-up UHF spectrum as it works in the 2.4 GHz spectrum. The tour for Lady GAGA currently uses 40 wireless beltpacks (all Tempest) in some of the most challenging RF environments worldwide. 8 base stations (each with 5 full-duplex beltpacks) are routed to an antenna combiner. Three antennas cover large, 20,000+ seat venues.

Tempest2400 Digital Wireless System

March 11, 2011

Clear-Com China Office Grand Opening (Jan 27, 2011)

Clear-Com, a global leader in critical voice communication systems, was joined by key Chinese customersand partners to celebrate its grand opening of a new office in Beijing, China. The new office will be the central hub for promotional activities and sales support of all Clear-Com products in China as well as provide after-sale technical assistance, shipment coordination and transactions that reinforce the company's distribution partners in this region.

With the addition of this site, the company looks to strengthen its international presence as a global voice communication company with innovative professional intercom products and unparalleled customer support.

March 7, 2011

Partyline Intercoms

Partyline (PL) intercoms are the simplest form of production intercom systems and are normally used for teamwork activities such as when several users, such as belt packs or camera intercoms, are engaged in a given common activity and they need to talk and/or listen to each other all the time.

Systems are usually full-duplex and are non-blocking, which means that each member can talk and listen simultaneously and there is no busy signal. Some signaling can be provided but usually not to the extent that every operator can selectively signal every other operator. Conversations on Partyline systems are typically non-private.

Present-day Partyline intercom systems may be wired, wireless or both. Most PL intercoms consist of power supplies (or master stations), user stations (ie, belt packs, speaker stations, main stations, etc.), interconnecting cable, headsets, panel microphones, push-to-talk microphones and a termination. Users typically wear headsets or talk through a gooseneck mic plugged into a station. Currently available Partyline systems offer high performance, low to moderate cost and can use one channel or multiple channels.

The advantages of Partyline systems include the following: 
  • relatively easy setup
  • simple operation
  • use of common cabling (standard microphone cables)
  • portability
  • clear, reliable communications.
The major disadvantage of two wire systems is interfacing between systems which, if not done correctly, could cause degredation of system performance. This degredation could cause a lack of selective calling to mutliple stations and limited privacy capability.

Click here to find out more on Clear-Com's Encore Partyline System.

March 3, 2011

Partyline Termination

The fundamental concept of Clear-Com Partyline intercom is that all channels are terminated in one location, preferably at a main station or power supply.

NOTE: There should be one, and ONLY one, termination for each channel in the system.

The concept is to minimize impedence changes on the line when user stations are removed from or added to the line. An un-terminated line will cause excessive levels, possible oscillation of line drivers and squealing in the headsets. An intercom line with double or multiple terminations will cause low levels and the inability to null the headsets.

The termination switches on the main station should be set to the OFF position only if the channel is terminated by another main station or power supply in the system. If there are no other main stations or power supplies terminating the line, the termination switch on each channel of the main station should be switched to ON. All unused intercom lines must also be terminated.

March 1, 2011

Welcome to COMM 'n Sense!

Professional Intercom. Hmmm.

Do I want wired or wireless? What kind of RF interference should I expect? How many users can it support? What kind of cabling does it need? Where do I place my antennas? What do I REALLY need and where do I start? The list goes on and on and on......... 

We, at Clear-Com, decided to have our experts de-mystify anything and everything related to professional intercom right here and now. Consider this your one-stop-shop for the information you need to create the best audio solution for your application. You can browse by topic, most popular post, or click on the suggestions tab to submit topic ideas. Help us to help you!

So what exactly is on this blog?
- Glossary of Industry Terms
- Links to Industry Resources
- Learn about Intercom Basics
- Wired Solutions
- Wireless Solutions
- Educational Videos
- Clear-Com Product Information
- Basic Clear-Com Information
- and so much more!!

Welcome to Clear-Com's new COMM 'n Sense blog!