Can I Use Regular Business Phones On VoIP?

Why Can’t I Use My Existing Analog Phones On VoIP?

When considering a new phone system, a client asked why she can’t use her existing business phones on VoIP.  We hope our answer will help you if you are also shopping for a new phone system and comparing analog and VoIP phone systems.

Hi V,

As per your request I will try to flesh out the details of your phone system quote.

You asked me why you couldn’t simply use your existing analog business phones on VoIP. Well, you can and you can’t. This is going to get a bit technical so let me try to explain:

Your current phones use what is called POTS which stands for Plain Old Telephone Service.  These phones can detect a dial tone and then use DTMF dialing to communicate over the wires by means of modulation changes over small electrical currents..

When your phone attempts to reach out to another phone it sends these signals over the wire to the phone company who knows how to interpret the beeps and sounds and route you to the appropriate destination; the other end of the call.

When you use VoIP, the electrical modulation is removed in favor of the IP part of VoIP (IP stands for internet protocol and is how one computer talks to another over the internet).  Because a computer cannot understand the way a phone communicates and a phone cannot understand the way a computer communicates, we need to use a translator (this was how modems worked the 80’s and 90’s).

A VoIP translator is a device that translates the electrical signals of POTS to the digital signals of IP and vice versa, and this translator can exist in different locations in the communication chain involved in a phone conversation.  You can have them in use with your analog phones, but with certain caveats. In the situation you requested, the communication chain would look like this:

Your analog phones<->VoIP translator<->internet<->VoIP provider<->analog Translator<->phone company<->endpoint

In this scenario the VoIP translator would be called an FSX adapter and would translate your analog phones to the digital VoIP signal. The Cisco SPA122 is a decent adapter and can be purchased online for around $70USD. You would need one on each phone in your office. You wouldn’t be saving any money here vs the quote as you’d have to shift the cost from the device to the setup. The labour involved in configuring these adapters is greater than that of a VoIP phone, so they don’t always make sense for small business.

Previously you had your system configured with the phones connecting directly to the Rogers box and the Rogers box acting as a pseudo FSX adapter for the Rogers Phone service (which you mentioned dropped a lot of calls). Unfortunately, with this type of situation there is no ability to program advanced functions like automated call routing, extensions, voicemail to email, etc. without adding a VoIP PBX inside your office. Which would basically mean installing a server inside your office dedicated to running the phones. Not ideal when everything is moving to the cloud.

The solution I typically propose involves using VoIP phones, so that the translator isn’t necessary on your end. And the way it looks is:

VoIP Phone<->internet<->Cloud based VoIP PBX<->VoIP provider<->analog Translator<->phone company<->endpoint

In this scenario, the VoIP phone speaks directly with the VoIP PBX which is a virtual “server” running in the cloud. It eliminates a possible failure point in your office and provides easier configuration and usually more functionality. Things like on screen display, multiple “virtual” lines per phone, busy indicators for a receptionist panel, etc.

Ultimately what it boils down to is that if you want the advanced functionality of a “Business PBX” you must decide where you want it placed, and then build the rest of the system around that. There are gotchas with each installation type.

Ultimately what it boils down to is that if you want the advanced functionality of a “Business PBX” you must decide where you want it placed, and then build the rest of the system around that. There are gotchas with each installation type.

With analog lines and an in-house VoIP PBX you will get the best sound quality and the most stability. This is the most expensive ongoing monthly cost.

With digital VoIP lines and analog phones you’ll be able to use inexpensive “off the shelf” phones but will need several difficult to program adapters.

With VoIP phones connected to a cloud PBX, you have a larger up front cost, but the most robust system and the lowest monthly cost.

I know this whole thread will probably create more questions than it answers, but I hope you now have a ‘big picture’ understanding that will help you make an informed choice to suit your present and longer term needs.  And we’re here to answer your questions and help you choose the right VoIP installation for your small business team.

So there you have it. This email helped V to decide, and we hope it helps you too.