Have always loved animation for nearly 30 years and have made that known numerous times. And it is worth saying numerous times being someone who steadfastly refuses to give in stereotyping animation as being just for kids as a lot of people do. Have always been especially fond of Disney, Looney Tunes and Tom and Jerry, but love most anime (namely Studio Ghibli) and Russian animation as well.
Know Hugh Harman (and Rudolf Ising) best for his cartoons that have a cute approach with a lot of sentiment, which is not going to appeal to some. There have been times where this approach has been done sweetly and charmingly, there have also been other times where it can be too cutesy and cloying. 'The Mad Maestro' is one of the former for me. It is cute and charming, but there is not as much cutesy sentiment as other Harman cartoons and it's more humorously entertaining than most.
Although not an animation masterpiece and there are much better, funnier and more imaginative music-themed cartoons, naming them would be unfair though, 'The Mad Maestro is among Harman's better cartoons overall.
The animation is rich in detail for design and backgrounds, vibrant in colour and crisp. The music is outstanding, then again it is Franz Von Suppe and his music works so well in animation ('Morn, Noon and Night' is one of his best-known pieces for very good reason), and used brilliantly to rousing and comic effect.
Characters here engage and despite their appearances are not too cutesy. They are not personality-deprived either and are suitably varied. The conductor's frustration is done very amusingly and one can understand it as well. The pace is energetic, the liveliness constant, and there are some very amusing moments throughout.
For all those outstanding qualities they are not quite enough to disguise that the story is one that is immediately forgotten by the viewer quickly and it's best to keep it that way. There's nothing new about it, not much of one at all and it's not hard to tell where it's all going to go.
Very nicely done on the whole though. 8/10