User manual for Unison Research amplifiers — I need the manual

I'm putting together an old audio system that includes a Unison Research amplifier. The manual doesn't mention anything about fine-tuning the balance or connecting a turntable. I’ve tried adjusting the inputs through trial and error, but sometimes the sound “jumps” and there’s noise. I’m especially curious about how to properly connect the preamp and subwoofer at the same time.

The manufacturer’s website doesn’t have a manual for this old version. Has anyone come across it and maybe saved a PDF? Are there any tricks for configuring the inputs without damaging the equipment? Maybe there are audiophile forums that have instructions like this. How do you usually find manuals for older audio gear?

Maybe you should try connecting it directly to the phono input? If there’s no phono input, you’ll need an external phono preamp. I found a diagram online in the user manual for Unison Research amplifiers . Take a look—is this the one or not? For example, I first set the gain on the preamp to minimum and then gradually increased it while listening for noise. That way, there’s less risk of burning something out. You can also use a Y-splitter from the line output. But I’ve only read about this; I don’t know how it works in practice.