Preamp help

I have a Consonance T1 pre that uses ecc82s. On the advice of others I had rolled tesla 802s in place and was an improvement over the jj82s. My question is can I safely use an ecc82 and ecc802 in series for each channel. The reason I ask is I had just upgraded my speakers and they are highly revealing. The 802s with this speaker has a somewhat recessed midrange but excellent imaging and clarity. The ecc82 has warmer and more forward mids but lesser imaging and clarity. I try one of each tube type in series for a short time to find it is the best sound I have from my pre to date. So if any one could advise on this Would be greatly appreciated Thanks
You are fine with whatever combination of these tubes in particular locations in your preamp work best sonically for your system and musical preferences.
Thanks Stevecham its good to know it will not damage the circuitry. I was getting very good sound from that combo I will go back to that and enjoy.