What audio components are heirloom quality?

None are. Unless your children may want to display under glass, the relics of a bygone age.

Instill a love and appreciation of good music. That will last a lifetime. It will enrich their lives beyond measure.

NO equipment will withstand the march of technology and social change.

One member on audiogon, who is a lawyer, did a lot of estate stuff, once posted: you will be amazed how often one man's treasure is another man's junk.

My parents never had high end gear, but they left me with a love of music. Music was always in the house. Piano, records, and singing. I still thank them for that.

Cheers

Rok2id:

+1

"My parents never had high end gear, but they left me with a love of music. Music was always in the house. Piano, records, and singing. I still thank them for that."

Amen to that Rok2id, me too.

IMO a well preserved LP (ex. Blue Note, Columbia 6-eye, Mercury, etc.) of a great recording is a work of art- the cover design, the notes on the back, etc.
it's so satisfying to look at and read the cover information while getting into tbe
tracks. And don't forget the fold-out albums either, and ones that came with booklets, catalogs, "zippers"...

What is considered an "heirloom" is a very personal thing. Not sure how to answer this usefully. Each family will have its own considerations regarding heirlooms.