Their 12AX7, 6L6GC-STR, EL34-B, 5881, 6550, KT120, and 6V6GT vacuum tubes have all become some of our best selling tubes for use in both audio tube amplifiers and vacuum tube guitar amps. We are very impressed with the quality of these new Tungsols. You will find many of these tubes in our Product Reviews. Many of these Tung-Sol vacuum tubes have customer reviews that show our customers agree. The Tungsol 12AX7 vacuum tube sounds great in just about any guitar amplifier. If you don't know what to choose, pick the Tung Sol 12AX7! As well, the Tungsol 5881 power output tube is a wonderful reproduction of the USA made 5881 from years ago. They ooze vintage tone. And speaking of vintage tone, the Tungsol 6V6-GT is another that nails it. This power tube is great for any vintage guitar tube amp when you want to keep that authentic tube sound without spending on rare NOS 6V6 tubes. The recently release KT120 power tube from Tung-Sol has quickly become a top pick for audiophiles looking for an affordable yet impressive KT88 vacuum tube replacement. The KT120 is now the OEM power tube used by Audio Research and Conrad Johnson for their hifi audio tube power amplifiers. Bass players, do not ignore the Tungsol 6550 power tubes for your Ampeg SVT amplifiers. These tubes are robust and sound great. If you have an old Ampeg amp that requires 6SL7 preamp tubes, the Tungsol 6SL7GT is low noise and reasonably priced.