Got any link to good echo cancellation hardware? Not that I'd every buy it, I'm just interested in tech (and businesses) that's not for average consumers.
I work at a big telco in the voice group and we still have tons of DMS 100/200/250s. Anyways some interconnections we have require Ditech echo canceller (no idea what model but apparently when we need them, we use spare ones or have to buy them on the used market). We have been migrating traffic to newer equipment and the new gateways have echo cancel built into them (e.g. Genband G9s)