Each cat’s purr is as distinctive as the cat itself, I’ve found. That is the case, at least, with my three (plus one). They even purr at different times and for different reasons, but that would be a whole new article.
Take Tungsten for example. She has a quiet purr much of the time. Sometimes, it’s a gargling type that one can feel in her throat but can’t hear. She is often on my lap on those instances, and I feel her contentment. Usually, however, it’s audible, and sounds like a hand slowly drawn over a level surface covered with smooth, round pebbles. Other times, when I come home after being out unexpectedly, her purring will be stronger, perhaps reflective of her feelings; she did not think I would go and was glad that I was back. After all, if I broke my routine and left her, how could be sure I would return? Her purr of relief is similar to the purr she emits after waking from a bad dream. There are times when her motor is so strong that her little thin body vibrates.
Josie used to purr inaudibly, just the gargle-like vibration in the throat I get from the orange one. Then she developed a stronger, louder purr, her two-tone purr. Now she starts her little motor going quite often. It’s not an attractive sound, really. It resembles the phlegmy, wet noise a person with a very bad cold might have. Yet I love to hear it. It took a long time for my Chubs to purr loudly and frequently. It’s rather an unattractive sound, objectively speaking, yet it's also serene and affectionate music.
Renn’s purr is rough and almost staccato. It isn’t continuous like the girl-cats’, but resembles the revving of a big truck’s engine. It’s the sort of sound that makes you want to clear your throat in sympathy. It can last a long time. When he is lying next to me, getting a chest-rub, either gentle or otherwise, the purr will go on and on. Eventually it subsides in volume, but not in feeling. Gradually, it will disappear, but you get the sense that it is like trying to reach zero by dividing a number by two: it diminishes eternally but never ends.
Finally, Tucker. The roly poly one has a very ready purr. He starts his motor as soon as you start petting him or stroking his head or neck. It’s a deep sound and steady, and is rather at odds with his habitually anxious or startled expression. It has endurance and will continue for as long as you are touching him. He also has a reserve purr, a low, gravelly one, deep in his throat, that he uses when you simply place a hand on him or talk to him kindly. It reminds me of someone who is embarrassed but pleased at the same time.
I like hearing my cats purr, as anyone who likes animals would. On Sunday mornings when I wake up later than usual, with the quartet of beasts on the bed with me, I’ve been able to get them all purring at once. It’s like keeping four tops spinning simultaneously. It’s a neat trick, but one we all enjoy. The sounds generated may be at odds with each other, but it has a harmony nonetheless.