Carver Raven 350 Amps

I am just using the cords that came with the amplifiers.  No issues, so no reason to change.

ozzy,
Been doing some reading on the DEQX products I and am fairly certain I am going to pick one up.  It will be nice to be able to room correct my own setup and it will do a much better job with subwoofer crossover and also allow the subwoofers to be integrated into stereo listening if I choose (which I can't do now.) 

erichgs,

Upgrading the power cords has provided a fairly impressive sonic improvement. Don’t sell this upgrade short.
Another improvement can be made by changing the supplied 12ax7 input tube to a vintage Telefunken tube.

And believe it or not I found upgrading the 1A fuse to a SR Red was also significant. Later on I’m going to replace the red for a blue fuse. But only after I’m confident the tubes have settled down and will no longer pop the fuse.

The DEQX has quite the learning curve, but once mastered it can provide great integration between subs, mains and the room.

ozzy

So only change the 12ax7 and not the 12at7?  Completely new to tube amplifiers and haven't even started researching tube rolling yet.  Anything I should be looking for when purchasing vintage Telefunken (stick with NOS, year, etc)?  Any place recommended for purchase?

erichgs,

Yes, according to Bob Carver the 12ax7 is the tube most sensitive to upgrades. Stick with Telefunken tubes that were made in West Germany vintage 1960's. Decent condition ones cost about $120-$150 a pair.
EBay is probably the best place to find a selection.

ozzy

Thank you Ozzy, have a pair on the way.  Also have a DEQX on the way.