As a first post and by way of introduction, I have been lurking for some time now, and I am pleased to be able to benefit from the knowledge of the folks on this forum.
So I've earlier this year finished building the VTA ST-120 Amplifier, and I'm super pleased with it.
I'm currently running it with the Brimar CV4003 in V1, and a matched quad set of Genelex Gold Lion KT88's.
The sound is simply excellent (to my ears, and to my taste), with well-defined bass, definition and texture and "air" between the instruments in the mid-range.
It's such a great amplifier and it's a major step up in sound quality from the Denon PMA-655R I've been listening to for so long.
This week I thought I'd try the Tung-Sol KT120 to see what they sound like.
I've read that other folks are running the KT120s in the ST-120... but alas I am having no success with this setup.
I can get the KT120s in the left channel to bias correctly at the recommended .500 volts, no fuses or bias resistors blown.
The first time placing the KT120's in the right channel, there was a low hum in the right speaker, a blue flash in the right rear KT120, and the 10 ohm 2W bias resistor blew (right, front).
With excellent guidance from Bob Latino, I replaced the 10 ohm 2W bias resistor in in the right hand channel, and the amp played as usual on the KT88s.
On the second attempt with the KT120s, the VARIAC fuse blew, and the amp went dead.
Replaced the variac fuse, and the amp on KT88'a all is good again.
Does this indicate that perhaps one or both of the RHS KT120's is "blown" (whatever that means)?
And any advice on whether it's worth negotiating a replacement from the seller?
Hoping someone can help out a noob...