Eric Preston / Software Development

I've been meaning to write about this for a while.

Whatever you do, do not purchase Cepstral Voice Starter pack from Digium's online store. For starters, I found out after purchase I might add, that at the time (a few months ago) and currently (from the periodic support ticket reports I keep getting) that their proprietary binary blob text-to-speech module (which they force you to use) doesn't work with Asterisk 1.6. (There was no mention of the fact, or versioning info on their storefront).

Secondly, it turns out you don't need their starter pack (costing around $80 when I purchased it) if you only want to run a single blocking channel of text-to-speech on your Asterisk box. Cepstral voices (direct from Cepstral's online store) work in this mode by default. You don't need Digium's broken (for 1.6) res_cepstral to have great sounding text-to-speech working in a few minutes for only around $30 USD.

Go to the Cepstral store instead and order a voice (test them out first, you can by downloading them without the license key) and you'll have a registration key immediately at purchase time to unlock the demo message at the beginning of the TTS sequence. Total cost for 1 channel, around $30 USD.

Furthermore, it turns out if you do buy Cepstral voices from Digium they won't ever work on the command-line. They will give you a funky Asterisk-only key to use with their binary blob which does not unlock the command-line Cepstral utilities.

If you get a key from Cepstral, their key will unlock the voice from the command-line and then you can use app_swift or similar to have cheap, great sounding text-to-speech in Asterisk in about 10 minutes; just don't get sucked into Digium's binary blob res_cepstral debacle like I did. You'll also be able to use the voice with all your command-line homebaked goodness.

To Digium's credit, they eventually refunded my $80, but it took about a month of wrangling with their tech support first. I wasn't at all impressed with their tech support. I explained early on that I was a Red Hat Certified Architect and I described my issues pretty clearly. I'll leave writing up my experiences with their tech support for another time.