The problem with some of the cheap emissions testers is they only run the tube at 30 volts, some of the better ones maybe up to 150 volts, the kt150 needs to be tested at a higher voltage. The best way to test them is in circuit.
KT-150 Tubes- Push Farther or Replace?
Hello All-
Seeking advice from others that may have been in this spot before. I’m currently running my trusty Audio Research GS-150 power amp and I’ve just crossed 2200 hours on this set of tubes. I have a new octet of KT-150’s waiting in the wings.
Within the last 200-300 listening hours I noticed that the bias was requiring adjustment after every 3-4 listening sessions. This seems to be driven by two of the tubes continually falling low in bias adjustment.
As the tube bias is slaved in pairs would/could it be beneficial to isolate the two tubes that keep falling low onto the same pair of sockets with the hope that bias can be more evenly maintained or does it just sound like it’s time for these to GO?
The amplifiers manual states that replacement should be around 2K hrs but I’ve read posts here stating 3K might be achievable. The current situation is lower quality bass response and weaker soundstage. Any thoughts would be appreciated.