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.