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          S-Class Brochure (PDF) IVX S-Class

S-Class w/Voicemail User Guide (PDF)

S-Class w/IAM User Guide (PDF)


Loaded with advanced capabilities yet amazingly easy to use, ESI’s patented IVX S-Class (IVX 56s) All-In-One Digital Phone System gives your small to medium-sized business the power to present your most professional side to your customers.

Big features; big capacities

IVX S-Class combines multiple first-rate, feature-rich systems into one tightly integrated unit:

IVX S-Class handles a configuration of up to 16 × 32 × 8.** And, when your business grows beyond this capacity, IVX S-Class can migrate to a full-fledged IVX E-Class or IVX X-Class system which uses the same ESI phones, minimizing upgrade costs and retraining.

Powerful — but friendly

Each IVX phone system says, “Good morning.” It teaches you how to use and program it. It reminds you to change your personal greeting after a trip. And it stands by, ready to assist you whenever you need help. There are three different models of IVX Digital Feature Phones; each is a compact, attractive addition to any desk, designed to simplify your telecommunications. Here are just two examples:

And each all-digital IVX Feature Phone works with either of the three principal IVX system classes (X-Class, S-Class, and E-Class), making it simple for an IVX S-Class system to migrate to a larger ESI system when your business grows.

Easy to choose; easy to use

Any IVX All-In-One Digital Phone System is an easy choice over other phone systems in its price class, and IVX S-Class is no exception. Its ease of use and feature-richness reduces staff frustrations, increases productivity and enhances your corporate image. And IVX’s unique integration provides call processing efficiency and cost savings previously impossible.

The Details:



* Requires Caller ID service from your telephone service provider.

** Configuration specs = 
CO (Central Office) outside lines × ESI Feature Phones × analog ports.