Digium VPMADT032 / 1VPMOCT032LF
The Digium 1VPMOCT032LF module, which offers 128ms (1024 taps) of echo cancellation across all of its channels, improves upon the older VPM100M echo cancellation module, that only offered 32ms of echo cancellation. The 1VPMOCT032LF provides the same toll-quality G.168 compliant echo cancellation found in Digium's HPEC software-based commercial echo canceler. The 1VPMOCT032LF is immune from any system CPU spikes that might otherwise affect a software-based solution.
*In September 2011 Digium changed the p/n on this sku from 1VPMADT032LF to 1VPMOCT032LF*
For Asterisk users who connect to the PSTN, the most common type of echo is hybrid echo - the echo introduced by the impedance mismatch between 2-wire and 4-wire telephone circuits. The echo manifests as a distorted and delayed reflection of the users voice while in conversation with an external party through the PSTN. Asterisk itself offers a range of software-based open source echo cancellation routines that are moderately effective in eliminating the hybrid mismatch echo that most Asterisk users experience. However, there are cases in which these algorithms are not effective. To combat this, Digium
introduced DSP-based echo cancellation modules for our multi-port T1/E1/J1 cards and our 24-port analog card.
Digium 1VPMOCT032LF Features:
- 128ms Echo Cancellation Module
- Compatible with Digium TDM2400P, AEX2400P, TDM800P and AEX800P
- G.168 Compliant