Manufacturer checkups

Thank you. Good posts.

Sorry, my initial post was not very clear. My older preamp was not sent to Lamm for inspection, and I do not particularly suspect it has problem. I have wondered, though, if it is supposed to sound better. I am just too un-technical to know if that is a reasonable stance, that parameters may have drifted off or something. Along with the many classifieds advertising equipment that was just checked out by the respective manufacturer, I began to wonder what others' experiences have been.

Some older gear might be in need of some refurbishment, such as new caps, re-bias etc.. If the unit in question comes with detailed documentation of the "checkup", even if it was for a repair, I'd consider it a plus.

I wouldn't be so optimistic as Sidssp.
If you hear

checked out last month by the manufacturer and given a clean bill of health

very often it spelled
"I pluged the unit and turned on and lights on" with no further testing.
When I open such units and see that there's 25 years old dust, I realize that spelling is totally different from what you're hearing just like in English101.

I have two friends, who when they buy used gear, often send it back to manufacturer for inspection, cleaning, calibration, whatever. Makes them feel better, and often not very expensive. Never do it myself.