Dick Cavett writes about the night of May 6, 1972 when Groucho Marx appeared at Carnegie Hall in New York. Most of the article is excerpted from the columnist's book, Eye on Cavett, a fine volume that is long outta-print but worth tracking down.
After the concert, a two-record set was issued called An Evening With Groucho which purports to be the audio from that performance. I am told it is only partially from the Carnegie Hall show and that a lot of the material on the album, perhaps the majority, was taken from a "warm-up" performance that Groucho gave at Iowa State University before taking the show to New York. The player below will allow you to listen to the record in its entirety. There are arrow controls there that will allow you to skip ahead or backwards and you may want to know that the first cut is an overture played by a then-unknown pianist named Marvin Hamlisch, the second cut is Dick Cavett introducing Groucho and the third cut is Groucho's entrance plus a song in which he is joined by Erin Fleming. After that, the cuts are anecdotes and the occasional song…
Frankly, on the record, he doesn't sound as bad to me as Cavett's article makes him out to be. Perhaps this is evidence that much of what we hear on it is from Iowa. Or maybe I feel that way because I attended Groucho's subsequent Los Angeles concert on December 11, 1972 where he really was in such bad shape he shouldn't have gone on. Compared to what we heard that night, the record sounds pretty decent for a man of his age. I wrote about it in this article…and if you go read that piece, don't stop there. Click the link at the bottom of the page and go on to the second part.
Groucho gave one other concert — after New York but before Los Angeles. It was on August 11, 1972 at the Masonic Auditorium in San Francisco and it was apparently the best of the four. Two weeks after, he suffered a stroke which explains why the L.A. engagement was so painful.
As far as I know, the only record of the San Francisco appearance is a partial audio recording that has a few bad internal edits and a number of defects. Still, the clear portions sound pretty good. You can listen to about a half-hour from the show on a player over on this site. (And can you believe the prices in the above ad? $6.50 for the best seat to see Groucho Marx? Even for '72, that was darn near nothing.)