Which tubes to buy

I remember that many years ago, Psvane tried to make a KT120 and they were notoriously unreliable. Maybe they’re better now, but there’s no way I’d trust a new KT150 from them until it’s had a lengthy, good track record under its belt.

You could ask ARC their thoughts on this tube, but my guess is they won’t be too keen on that. Upscale doesn’t sell JJ or Psvane tubes for a reason.

ARC sez you can use KT120, KT88, and 6550's. They just don't necessarily indorse them. Sounds like they voiced the amp for the KT150's.

I have an ARC Reference 160s as well. My preference is to get the tubes from Audio Research... because they extensively test them and I want to support this great company. I have a spare quad of power tubes I bought from Upscale just in case I needed for testing. In general, I don’t tube roll with Audio Research equipment as they were carefully voiced. That said, a friend of mine tried a GE NOS 6550 in his ARC Ref preamp an liked it... so I ordered one just for fun.

The Tung Sol KT120s have a good reputation.