[Asterisk-Users] EC needed in all-digital situation?

[Mike Fedyk]

Warren wrote:
> So the next question becomes...  Is hardware EC necessary or can * 
> handle it in software?  I am looking at some pretty beefy hardware for 
> my platform, a Dell PE2850 with dual Xeon 3Ghz processors and plenty 
> of RAM to spare.
Can your processors handle the load, yes.  Do you want to use software 
echo cancellation?  Most likely no.

Should you get a Digium card with hardware echo cancellation?  That's 
debatable. 

For ~$300 difference the Sangoma four port DS1 card w/ echo can gives 
you 1024 taps of echo cancellation.  In comparison the Digium TE411P w/ 
echo can gives you 512 taps with 32 or fewer channels active.  Once you 
go over that, you get 128 taps.

"Digium's hardware echo cancellation provides 64ms across 32 channels; 
however, when it scales over 32 channels it is reduce to 16ms per 
channel across all channels."
http://blog.voipsupply.com/asterisk_hardware/

If you want to support Digium/Asterisk, then buy a support contract.  
Admittedly I haven't worked with Digium's DS1 cards, but I have used 
their TDM400p cards.  I can tell you that the software echo can isn't 
that good.  Of course listen to others who are using Digium's hardware 
echo can.  In fact, I'd like to hear from people who have had good 
experiences with it (and especially if you have bad experiences with 
sangoma hardware echo can).

Until Digium's products have an echo can with a longer tail, buy Sangoma.