From the Tom Crown website:
The first mute in our mute family was what we now call the Classic straight mute. It came into being as a result of my search for a piccolo trumpet mute. I was playing in the Lyric Opera orchestra and in 1967 the Lyric scheduled Le Chant du Rossignol by Igor Stravinsky. My part was a D trumpet part, more easily played on a piccolo trumpet. There were many muted passages and not having a piccolo trumpet mute, I asked Adolph Herseth if he had one. He did and I borrowed and used his mute on all the performances. It worked very well. I also started playing piccolo trumpet on radio and TV commercials and felt the need of having a piccolo trumpet mute at hand. It was embarrassing borrowing Bud’s mute so often so I asked him if I could have his mute duplicated. He said yes I could. I found a metal spinner and had it, what I thought, copied. The copy, however, was not exact. It was larger and really not suited to the piccolo trumpet. Then one night, trying different corks on the mute, I tried it with the C trumpet and higher corks. Wow. It was like the discovery of sex. What a mute. I had a dozen made for friends in the CSO and the Lyric Opera. I sold four to the trumpet section of the Philadelphia Orchestra. I then asked the original metal spinner if he could make 100 copies of the mute. He balked. He wasn’t used to dealing with such quantities. I found another metal spinner who was happy to do orders of 100 and then 1,000 mutes per order. Later, at the suggestion of a friend, I had mutes made using aluminum, brass and copper in different combinations. This also worked well. One trumpeter swore by the copper end mute another the all brass etc. This was the start of the Tom Crown Mute Company. We have sold more than 200,000 classic trumpet straight mutes to date.