atcomsystems.ca/forum Forums TDM Business Telephone Systems Inter-Tel Telephones & Systems IP settings confusion

Under IP connections\Backplain call configuration there are settings for Echo suppression and sensitivity level. Then under IP related/call configurations these settings reapear along with some others.

Why are these settings in two places? They can be adjusted differently so it seems there not tied to one another.

Thank You!

I think it's because the IPRC can now be used for both endpoints and networking. This way, the endpoints can use a different suppression scheme from network calls. Yes, no?

Not sure about the networked call. I know adjusting the backplain config settings on echo changes the suppresion on outgoing calls. Changing it under IP related seems to do nothing.

When you say networked, do you mean one system networked to another system?

What I'm trying to nail down is why intercom calls have near perfect sound and outgoing calls have much more trouble with echo. Both conversations IC or POTS calls are going over the same internet connection.

Thank You!

Can you post w/ more info regarding your voice topography? You're saying POTS and IC calls are using the same 'internet' connection. Can you explain how your voice network is laid out?

IP to POTS calls are much more succeptible to echo. It's in the 2 to 4 wire converion. Anytime an IP call passes through the 2/4 wire hybrid, there is a certain amount of reflection. This is the echo. An IC call would not touch the hybrid, hence no echo.

What version is CP, IPRC, endopint? Also the topology SFG requested.

Axxess 8.201

Endpoint 8660
Ver. 8.1.0
Boot 09Jun00

IPRC
Ver. 9.0.0
Boot 1.2.3

There is an Axxess system in one location using disital handsets and SLA's with a IPRC card installed and connected to a cable modem. This system has 6 analog lines.

The second location is just down the street with two IP 8660 endpoints connected to another cable modem. Ping time between the two locations are very low around 9 to 15ms. I ran the network qualifer between the to locaions and everything looks good.

IC calls are great. Sometimes a skip in the conversation but no echo. On a outgoing line though there is usually echo. Some times the calls are good but usually there is echo. I can pick up a line with no call on it and talk into the handset and hear a good about of echo.

On the digital handsets in the main location there is no echo. Only on the IP sets. With my limited knowledge it seems that if the analog lines were the issue then all phones would have echo.

I'm just trying to nail down the source of the problem.
Thank You for any help you can give!

The analog lines aren't the issue. It's the 2 to 4 wire conversion hybrid. You can try setting the HYBRID BALANCE on each analog trunk to SHORT. This will probably handle 75% of the reflection. Also try adjusting the BACKPLANE ATTENUATION LEVEL between 3 and 6. Any more and the volume will be too low for general conversation. For the rest you can play with the ECHO SUPPRESSION SENSITIVITY LEVEL. It may offer some fine tuning.

For the Backplane Attenuation change to take effect, you must reset the IPRC.

If the above steps do not mitigate echo enough, try attenuating the trunks -3 DB and test.

Thank you for the info. The hybrid balance is set to normal currently. I will change it to short on Monday and retest. Then I will try the attenuation level if it still needs more help. I hate to reduce that to much because the volume on calls is already low. I have to set the handset volume to max already to have a conversation on outside calls. IC calls are very loud.

Now I see why changing the attenuation levels did nothing for me. I never forced a reset.

So is the echo settings under IP related station to control the echo in the network between the IPRC and endpoints and the setting under backplain for echo between the IPRC and CPC?

Thank you for the great help!!

One more question. Will changing the trunks to short make any changes to the regular digital handset or sla's?