Source note · Echo on VoIP calls
Cisco states that the default voice-port impedance of 600 ohms is consistent with most PSTN and PBX lines.
Checked 2026-09-25
A default of 600 ohms is consistent with most lines on the PSTN and PBXs.
- Vendor
- Cisco
- Product
- Cisco IOS voice gateways (analog voice ports)
- Subsystem
- analog-hybrid
- Deployment
- on-premises
- Region
- not restricted
- Release range
- as documented 2008-04-02
- Checked
- 2026-09-25
Sources
- Troubleshooting Echo Problems between IP Phones and IOS Gateways — Cisco · tier 2 current vendor documentation · Step-by-step Procedure to Troubleshoot and Eliminate Echo
Cite this note
APA
WarmTransfer. (2026, September 25). Echo on VoIP calls: source note echo-on-calls-impedance-600-default. WarmTransfer. https://warmtransfer.net/knowledge/claims/echo-on-calls-impedance-600-default
BibTeX
@misc{warmtransfer-claim-echo-on-calls-impedance-600-default,
title = {Echo on VoIP calls: source note echo-on-calls-impedance-600-default},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/echo-on-calls-impedance-600-default},
note = {Source note echo-on-calls-impedance-600-default, checked 2026-09-25}
}