said by not quite right:
Why would I get a Dedicated Fax line for $10 a month vs getting just a second line for $5 a month? Is there something I'm missing here?
In theory, the dedicated fax line is provisioned for optimal performance for fax transmission. This includes setting the ATA for maximum bandwidth, and also permanently disabling such things as call waiting, call forwarding, voicemail, and other such things that can interfere with proper fax transmission.
Most newer Vonage compatible ATAs will automatically change their settings for fax optimization when a fax tone is detected, but some older ATAs did have problems doing that (and I don't think that any of them will disable call waiting or call forwarding automatically when a fax tone is detected).
If you manually setup your second line to emulate the fax service settings, there should be no difference (but it will need to be an actual second line and not just a second number). Your mention of $5 per month makes me think that you may be thinking of a second number and not a second line, and there is a big difference.
EDIT: I just logged into my account, and clicked on "Add a Line", and I did not see any $5 per month plan offered (the cheapest was a $9.99 "bait and switch" offer. I did however see the $4.99 Virtual Phone Number feature. A Virtual Phone Number would not be a good choice for fax usage because it is not really a second line, and you would need to permanently disable call waiting, call forwarding, and voice mail for your primary number to make it work reliably with faxes (and you would also not be able to fax and talk at the same time, since it is not really a second line...and there would also be the problem of not knowing whether or not an incoming call was a fax or a voice call until you answered the phone).--
History does not long entrust the care of freedom to the weak or the timid.
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