KT77, Matched Quad (4 tubes)

First, I want to give a huge shoutout to Viva Tubes for their customer service and fast shipping. I had a tube that took some damage during shipping apparently, and Viva Tubes had a new replacement tube that is matched to my remaining KT77's shipped out the very same day. Wow!! I can only compare the sound of these GL KT77's to the stock cheap KT88's that shipped with my Willsenton R8 integrated stereo amplifier. The sound is slightly warmer and much smoother than before. The stock tubes could be a little too strident at some higher frequencies to the point that they nearly hurt my ears at times. Things became even more holographic with the GL KT77's than before, and I feel like the soundstage is even wider in every possible direction (my sound stage was amazing before, but these made a big difference). I'm definitely happy with my purchase, and just as happy with Viva Tubes. Those guys rock!

After reading many reviews on Amazon and other technical forums I replaced the stock Chinese Shugang tubes in my Yaqin MC-10T with these Gold Lion tubes. I was very pleased with the results. The Gold Lion Tubes made the Yaqin sound a bit warmer and more robust while keeping that "You are there" soundstage that tube amplifiers are known for. I know there are significantly more expensive tubes out there but I haven't tried them so I can't compare them to the Gold Lions. All I can say is compared to the stock tubes, the Gold Lions improved the sound in my Yaqin and were well wort the cost.

Used in a PrimaLuna Evo 300 that is known for being tube-friendly. Really enjoyed the change in sound quality after 20 hrs break-in. After about 230 hours total use, one (or more) of the tubes went bad. Starting making extremely loud "tearimg" / buzzing sound in both channels. Switched back to stock tubes and the problem went away completely. Swapped the KT77s back in, and before the amp could even finish its warm-up cycle, it was making the horrendous sounds again that i feared could damage my speakers. Swapped the stock tubes back in again, and no problems in 20 hours of listening since. Never dropped a tube and they were treated with care. They're now relegated to my bookshelf as a "decoration." Money down the tubes (pun intended).

Just installed my Gold Lion KT77 matched tubes from Tonal Tubes. Delivery was just a few days and the product came undamaged - great for such a fragile item. The tubes sound significantly better than my previous J&J EL34, which I thought were pretty good. More base, more punch, more dynamic range and better sound stage, without sacrificing mids and highs. Easily available thru Amazon Prime, matched within 5%, and I didn't have to "deal" with the loud mouth from La Verne, California. Thank you Tonal Tubes.

I like the tubes, great sound! Very good seller, fast shipment.

Replaced EL34's in a Prima Luna Evo300. A firmer and thight bottom end at lower volume

I was initially excited about these tubes due to their almost across the board high ratings. After having them for approximately 5 months one blew suddenly. I have tube amp where I can and do set the bias on power tubes and am very careful to do this when I change tubes. I bought another from the same vendor thinking that the tube was bad and was out of warranty. After having the new one for a couple of months another one blew in a different position on my amp so its not the amp. I have Mullards, JJs and Svetlanas in EL 34 and none have given me any problems at all even after 100s of hours using them. Overrated and overpriced.

Very smooth with perfect low-end punch. Highly recommended. Used these in my Prima Luna tube amp.