I recently upgraded my comcast cable internet from 6Mbps (speedtest results ~7Mbps downstream) to 20Mbps (speedtest results ~28+Mbps downstream). I also changed modems from a moto surfboard docsis 2 to a docsis 3.
 
I was expecting a noticeable speed increase when downloading files but the performance increase is dismal compared to extra cost.
 
With the 6Mbps service I could DL a single file at 980KB/sec according to firefox download mgr. With the new service 20Mbps I can only DL a file at 1228KB/sec (1.2MB/sec)  I have spent hours with Comcast on the phone with no resolution but they do agree it is a problem.  One of the techs said that I should probably be seeing closer to 3.5MB/sec on a file download. I have pulled my router out just to ensure it was not a problem and nothing changed.
 
I did my file download testing by downloading from Groove3 and from Cakewalks servers using Firefox 31 download mgr. both were reported at 1.2MB/sec DL speed.
 
Just curious as to what type of download speeds others are seeing when they DL files.
 
Kind regards,
Rick

Using a 12Mbps connection my download speeds are much faster using FDM than the internal download manager in Firefox.

I will give that a shot. Thanks scook!
 

FDM gives me a DL speed of 3494KB/s much better then the 1228KB/s from Firefox 31.  Looks like this will come in real handy if I can just figure out how to use it...
 
Thanks again scook!

It integrates into Firefox or launched from the right-click context menu. To add FDM to Firefox open FDM Options > Download > Monitoring and check the browsers to monitor.

Oh Wow! This is pretty cool. Feel like I got a new toy...

It is a nice tool. The biggest problem with using addons like FDM is the frequency of Firefox updates. Sometimes Firefox updates come so fast, it will disable FDM after an update. The FDM website covers how to modify the install.rdf to get around the problem. Right now the current version of FDM will stop working with Firefox 33. For me, it is worth the extra effort to learn how to keep FDM alive.

There are two ends to a file download, the speed you can receive at, and the speed that the server is willing to send at. When you do a speed test you are downloading a file from a server that is willing to push the file as fast as you can take it. Often the servers are not going to be sending a single connection thread at the maximum speed you can accept. Download manager software typically works by opening multiple connections to the server, and if the server is capable of doing so, splitting the file into segments that all download simultaneously and then recombining the file at your end. 

So that is potentially the 'sectioning' I see happening in the FDM that scook told me about. It really works great and cuts the time down on a single file DL. 
 
I wondered about the servers being set to only provide a certain speed for a single DL that is why I tried the Groove3 and Cakewalk servers as they normally send stuff pretty quick but I guess I just went above that limit. FDM has solved that problem.
 
Thanks for the reply!

Yes, FDM provides control over how many concurrent download parts it will attempt. Some servers do not allow managers like FDM to connect unless they are configured to only use a single connection. Fortunately most servers allow multiple connections. For the servers that block multiconnection downloads either reconfig FDM or when FDM asks to perform the download, cancel out and let Firefox handle the d/l.