My PS-100 started making random crackling sounds, and based on other posts, it seems I may have a faulty tube. I bought new replacement tubes (PI and power tubes), but I got KT-88s this time because they handle higher voltages than 6550s, hoping they are more reliable, and the PS-100 manual says they are interchangeable.
However, upon trying to install them today, both power tubes physically rub and are sitting against the smaller 12AX7 tube on both sides. I know my PS-100 runs hot, so can I run them like that, and is that normal when installing KT-88s in the PowerStation, or did I make a mistake reading the manual and need to get 6550s? Super frustrated as I just want to get my PS-100 running well again.
Plate voltage handling capacity is not necessarily a function of tube type as much as its specific application. In the case of the PS-100 it makes no difference whether you install 6550s or KT88s.
The performance will be virtually the same for all practical purposes. However, using 6550s will definitely allow more clearance to the preamp tube and rear cover.
These days we use and recommend JJ and Sovtek 6550s.
Hi Dave,
Thanks for your reply. In this case, since I have almost no clearance with my PS-100 and the KT88s I got, with both power tubes wedged against the preamp tube, my question is can I run it like that, meaning with the tubes physically touching each other, without issues, or should I just cut my losses and get another set of 6550s to avoid problems or premature wear down the road?
That might be pushing it. If it’s just sitting in one place all the time and the tubes are just barely touching the rear of the top cover, you’re probably OK.
If it’s a really tight fit, and you plan on moving it around. Go wioth the 6550s.