[Freeswitch-users] [Out of curiosity] Why not use a voice modem for FXO?

[Steve Underwood]

On 05/27/2010 06:49 AM, GillesToo wrote:
>
> Anthony Minessale wrote:
>    
>> A FXO card works as well as it can but traditionally requires an
>> echo canceler if you want quality that will not draw complaints
>>      
> Why do FXO cards generate echo issues while ATA don't? For instance, there
> are a lot of people complaining about echo with the Linksys 3102.
>    
ATAs contain echo cancellers. The SPA3102 contains one, but it seems to 
be badly broken. The FXO cards are mostly dumb. Its up to host software 
to provide functions like DTMF decoding and echo cancellation for them. 
Try OSLEC with most FXO cards and you'll get great results.
> Anthony Minessale wrote:
>    
>> The good thing about an ATA is that it's self-contained and translates
>> everything into SIP for you when you don't have room for hardware.
>>      
> Actually, that's why I prefer to use a PCI card instead of an ATA: No need
> for a transformer and a cable to connect the ATA to the Freeswitch server,
> and only one cable left to connect the PCI card to the wall plug. With
> non-techie customers, it seems like a safer solution.
>    
Steve