Not exactly, no.
The Countryman is a VERY clean DI. It doesn't affect the incoming signal in any way. That means if you plug it into the speaker output of your head, the tone coming out of your amp will be sent directly to the board. It will be a very good representation of your tone before it gets to the speaker cab. It will not sound like a mic on a speaker.
If you want a DI that can be plugged in between head and cab and does sound like a mic on a speaker, you want the Radial JDI or JDX.
Ok, thanks for the clarification. I was looking at the JDX a while back and thought that was the one for me. Then the RNDI came out and I forgot about the JDX.
Maybe the JDX + and LPF would be the ticket......