Sorry, but the evidence mostly contradicts your hypothesis.
Tinnitus occurs inside the head, and is usually not helped by devices to concentrate or amplify sound waves. Yet Beethoven used various ear trumpets, etc. for quite a while, with some success.
Tinnitus if fairly stable; only slight increased effect on hearing as a person ages. But Beethoven’s hearing loss clearly got worse as he aged, typical of normal (non-tinnitus) hearing loss.
Tinnitus is a symptom that most commonly occurs during quiet times (no outside sounds entering the ear). Beethoven’s hearing problems occurred during non-quiet times – he was trying to hear a piano or even a whole orchestra.
The problem with that is the part about putting the brush or roller in the right spot and at the right amount of pressure while blind. Designing home décor while blind, or drawing in color while colorblind (see the works of Ciruelo Cabral) can be done, though.
I’m not a master programmer but the little programming I’ve done took place before it was possible to have a window with text and one with your program open at the same time, so we’d write the code on paper, type it, correct any errors, retype… until it worked. There were several times we got simple programs to work correctly on the first typing, no corrections needed. I also had a boss who, while horrible about communication, kept track of every table, field, their relationships and the programs using them in this huge database we were building, all in her head (she even remembered the flipping long-ass names).
I may not have presented the idea very clearly - I mean to say was the combination of severe tinnitus and a loss of hearing.
Sadly, until I return home, Wiki is the only resource I have. In the article on Beethoven and his hearing loss, tinnitus is the first symptom mentioned -
From the Wiki article on tinnitus -
You may well be right that my hypothesis doesn’t hold water - at any rate, what I mostly wanted to point out was that deafness does not necessarily mean hearing silence instead of sound - it may well mean that the sound you wish to hear is buried in noise.
As far as determining what it was exactly, we’re just up against a lack of diagnostic evidence.
I missed the edit window -
From the Wiki article on Tinnitus, in the chapter on causes of tinnitus, loud sounds are listed as a potential cause -
If Beethoven had a predisposition to tinnitus, or a particular sensitivity that allowed loud sounds to cause tinnitus more readily, it could very well be that his work with orchestras of the day exacerbated the problem. Many modern musicians, in classical music and in rock, have had their calling cause their deafness. Yes, Beethoven’s orchestras weren’t as loud as a modern orchestra - that’s why I included the remark about a predisposition.
Some new research just out (perhaps someone could provide a gift link):
Kevin Brown, an Australian businessman with a passion for Beethoven, owned three of the locks [of hair] and wanted to honor Beethoven’s request in 1802 that when he died doctors might attempt to figure out why he had been so ill. Mr. Brown sent two locks to a specialized lab at the Mayo Clinic that has the equipment and expertise to test for heavy metals…
The result, said Paul Jannetto, the lab director, was stunning. One of Beethoven’s locks had 258 micrograms of lead per gram of hair and the other had 380 micrograms. A normal level in hair is less than 4 micrograms of lead per gram. “It definitely shows Beethoven was exposed to high concentrations of lead,” Dr. Jannetto said. “These are the highest values in hair I’ve ever seen,” he added. “We get samples from around the world and these values are an order of magnitude higher.”
I heard on the radio, and the New York Times article also mentions, that May 7th was the 200th anniversary of the premier of Beethoven’s Ninth Symphony.