This an early AVA preamplifier built into a gutted Dyna PAT-5 chassis. What an original PAT-5 sounded like is immaterial, it is not a Dyna circuit set any more.
The resistors in your photo do run hot, but well within their ratings. They are simply dropping resistors, along with shunt regulator zeners, to take the raw plus and minus 60V power supply down to the needed regulated plus and minus 15V.
We did use the original Dyna power transformer in this early product because it worked fine, even though it had higher voltage then really required.
This is obviously one of our solid state circuits, but I cannot tell which without seeing photos of the audo circuit boards.
In good working order it is certainly worth at least $200 and will rival brand new preamps in musical performance.
Frank Van Alstine