6N6P (6H6П) NOS Vacuum Tubes, NEVZ, Amplitrex Tested and Matched Pair, Audio Amplifier - 9-pin - Platinum Grade - Matched Pair (6H6П) 6N6P (CCCP)

Very happy with the sound quality and shipping materials as well to keep the tubes safe were top notch. Application is a Schiit Valhalla 2 Headphone amp. Brought the life back into it, when paired with 6N1P/6H1N-EB pre-amp tubes from sovtek.

Was using GE Jan tubes, like them but decided to try something different. The mids and uppers on these are phenomenal. The GE tubes are hard to beat, but these do it in my opinion.

The packaging was the best I’ve seen. Also tubes were perfect and matched perfectly. Will buy from this vendor again

These are definitely an upgrade from the factory chinese tubes in my little dot mk2, I've burned in the chinese set and compared back and forth and the difference in gain is definitely not my imagination. it sounds like the amp is ever so slightly more powerful driving sennheiser hd58x compared to stock, and really they sound great. The stock chinese tubes are also surprisingly decent though to be totally honest. I notice a much bigger difference to the sound signature when swapping the smaller driver tubes than I notice when swapping the rear power tubes. In reading online I've come across a gold-platinum grid version of this tube in addition to these ones. Apparently they sound somewhat different, I've ordered a matched quad off ebay from a UK seller, but I would love to see riverstone audio selling a platinum grade set of the same tube from the 1970's. they both seem to be available at similar prices at least in moderate quantities.

Replaced the stock Chinese tubes for these. A perfectly matched pair. Everything was packed well & item arrived on time. Will definitely order again for all my tube needs. I really have no long review concidering these are just the power tubes so it's not gonna make a difference in the sound. I just figured since I replaced the tubes that provide the sound I would replace these also just for longevity purposes.

OMG!! Amazing fidelity!!! Second to none..Buy it while it's cheap!!

AMAZING care taken with packaging and delivery. Awesome little details that prove they really care about the product. Tubes perfectly matched and results of testing printing plain on the box. Tubes marked A and B and sound great. I'll be using Riverstone Audio for all my tube needs from here on out.

I ordered these tubes to replace the rear/"power" tubes that came with my Schiit Valhalla 2. They arrived on time and very well packaged. To my ears, they sound very well matched. I'll definitely buy from Riverstone again!