What Did I Do Wrong?

I have a Rogue Cronus Magnum integrated with the KT120 tubes. I wanted to try the EL34 sound in my system so I purchased 4 Shuguang EL34B tubes which were graded and matched from Upscale Audio. I checked with Rogue and was told to set the bias at 30ma. I received the tubes today, installed them and let them warm up for 30 minutes. The sound was a little ragged and distorted and try as I may, I couldn't get a reading on the bias meter.

Thinking I wrecked the amp, I reinstalled the KT120 tubes (thank God I marked which socket they came out of) fired the amp up and the sound is again full with no distortion. I checked the bias on the KT120's after 30 minutes and the bias on one tube was off a little.

Why did the EL34 tubes sound distorted and why couldn't I bias them? What did I do wrong? Do you think these tubes are all toast now?
I already sent Nick an email and stated I would follow up with a phone call tomorrow.
Stereo5...please let us know what you find out. I'm kinda intrigued by the problem.
This is what is best in the audiogon forum communities; great help and sometimes even a designer or manufacturer will pop in to help as well; Ralph from Atma-Sphere as a example.
Talked to Nick at Rogue today and he confirmed the EL34 tubes do work in the Cronus Magnum. He said I may have to turn the bias pots up to a dozen turns to get the tubes to bias.
Well ... that turns out to be a very good answer. At the very least, you now know that the EL34s did not damage the amp .. a very comforting response.

It is curious that the web site didn't mention that the amp could switch hit between the two tube types. As I said, maybe the Cronus II is KT-120 only, but the earlier version is the switch hitter.

In any event, glad to hear the news.