I had a tube burn out in my amp and i was freaking out because it happend 3 days before a gig so i went and talked to my dude at a local music store and he told me that he had been using these for years and that he liked them better than the ruby tubes that i was using. I totally see why he likes these better, because im sold on them as well. My amp had more defanition, clarity, punch, and presence. My band playes in A# and we played after i got the new tubes and that was the first time that i was ever able to hear myself on stage and i got a lot of compliments that people noticed a good difference in my sound and i noticed it. These are awesome sounding tubes.

I was on my way to a gig and as I was driving I hit a very sharp speed bump and my amp(fender HRD) fell backwards onto my pedals board and it shattered the tubes. Luckily, a friend pointed out that there was a music store near by. I quickly drove there but when I arrived I couldn't find the tubes I usually use. I saw these tubes and they were about the same in price so I tried them. I arrive at the gig and I stick em' in and start sound check. The amp warms up and is ready to go and I'm not expecting much because these were last minute tubes, but then I played that first chord the angels sang. These tubes have amazing clarity and punch to them. All my band mates couldn't believe how much different it sounded. 5 years later I still use them and don't plan to change anytime soon =).

Well not really steel but very durable. I'm not afraid to load my amp into the back of the van and drive off because I know these tubes can handle it. As for the sound they are great. Amazing dynamic range and good balance of lows, mids, and highs. The best tube I ever bought and not too expensive either.

Overall: Durable Large and balanced dynamic range Economic

What more can you ask for?