Worth repairing Essence Amp?

based on the limited info you have provided there is no one here that can credibly tell you

we have no idea what is wrong, what the repair cost would be, whether parts are available (some older transistors are nla), what the amp’s condiition is besides the one bad channel, and so on -- you get the drift...

if you love the amp, you need to do some homework and legwork, find a good tech to give you a diagnosis

Did you open it up and see if each channel is fuse protected?   Not uncommon for there to be internal fuses for each channel, power supply....

The designers name is Dale Pitcher. My understanding of his amps is that they were pretty complex but sounded terrific. Member audiobunker sold many products produced by Dale over the years. I am not sure if he can help you or not.

Audiobunker, Duane Randleman  of Automated Lifestyles in LeClaire Iowa did a great job helping me through this. He has someone able to service these amplifiers, also worked on my Essence pre amp, and gave very good recommendations for tubes on the Lazarus pre amp I was using as a phono pre amp that Dale sold to me some 30 plus years ago.  Highly recommended.

I would add I thought the prices very reasonable for the quality of amp, to replace of equal caliber with something new would have been much more expensive. They do apparently have some of Dale's schematics as well.