Hanslick was mentioned on another thead. I happen to have been pouring through a large number of Hanslick's reviews recently (one thing that people don't always realise is that, for all his reputation as a prophet of 'absolute music', over half of Hanslick's writings were on opera - he was particularly perceptive when writing about opera and other singers). But, in case people think that today's critics are harsher than ever before, try these (grotesquely unfair) comments from Hanslick after the premiere of Bruckner's Eight Symphony in Vienna in 1892:

Bruckner begins with a short chromatic motive, repeats it over and over again, higher and higher in the scale and on into infinity, augments it, diminishes it, offers it in contrary motion, and so on, until the listener is simply crushed under the sheer weight and monotony of this interminable lamentation.....

Also characteristic of Bruckner's newest symphony is the immediate juxtaposition of dry schoolroom counterpoint with unbounded exaltation. Thus, tossed about between intoxication and desolation, we arrive at no definite impression and enjoy no artistic pleasure. Everything flows, without clarity and without order, willy-nilly into dismal long-windedness. In each of the four movements, and most frequently in the first and third, there are interesting passages and flashes of genius - if only all the rest were not there! It is not out of the question that the future belongs to this muddled hangover style - which is no reason to regard the future with envy.....

In the Adagio we behold nothing less than 'the all-loving Father of Mankind in all His infinite mercy!' Since this Adagio lasts exactly twenty-eight minutes or about as long as an entire Beethoven symphony, we cannot complain of being denied ample time for the contemplation of the rare vision. At long last, the Finale - which, with its baroque themes, its confused structure and inhuman din, strikes us only as a model of tastelessness - represents, according to the programme, 'Heroism in the Service of the Divine!' The blaring trumpet figures are 'heralds of the Gospel truth and the conception of God'. The childish, hymnal character of this programme characterizes our Bruckner community, which consists of Wagnerites and some added starters for whom Wagner is already too simple and intelligible. One sees how Wagnerism educates, not only musically but also in literature.

But for a better side to Hanslick (and a type of review which one might not imagine, given his reputation), try the following from his review of The Mikado, which he saw in the Savoy Theatre during a trip to London in 1886 (it forms part of a fascinating 'Letter from London', in which he describes a London still very recognisable):

The Mikado is called specifically a burlesque. It makes no pretensions of being anything other than comical, and this it is in high degree, thanks not so much to the very simple plot as to the droll, wonderfully animated performance. The dialogue sparkles with inventive wit and satirical jibes, particularly in the conversations of the two ministers in the first act and in the negotiations with the Mikado at the close of the second, The passion for execution which runs through the entire piece may be accepted as a local characteristic of the régime in Japan; we may be thankful to the authors for having spared us, at least, the gory business of hara-kiri, for which the Japanese entertain a famous affection.    
( ) .......

   Sullivan has been accused of imitating Offenbach. I can only reply that to learn from Offenbach shows better judgement than to slander him. To be sure, Offenbach's luxuriant melody and scintillating esprit cannot be learned; but what can and shoul be learned from him is the concise form, the discreet mdoeration, the easy singability, and the modest orchestra. In all these respects Sullivan took the composer of Fortunio as a model, without sacrificing his own self-sufficiency. It is not expected that the English should attain the effervescent vivacity and the piquant charm of the Frenchman - but Sullivan, in his multiple-voiced pieces, shows himself the more thoroughly schooled musician. The practice which all English composers have in the madrigal is reflected in this musical comedy. Also to Sullivan's advantage is the fact that he is a cultivated singer. The vocal parts in The Mikado are so easily encompassed, and restricted to such a modest range, that big lungs and technical virtuosity are no more prerequisites for their performance than they were for the musical comedies of Adam Heller, Monsigny, and Grétry. The orchestra subordinates itself modestly to the song without renouncing the employment of livelier colours or illustrative devices at the right time and place. The music of The Mikado is a step backward to the older operetta style - in other words, a step in the right direction.
    I am aware that in English musical circles it is fashionable to look down the nose at The Mikado and to dismiss Sullivan as a renegade or as a lost soul because of this 'Offenbachiade'. . . . . . . He is by far the most talented of the young English composers, and has already made a name for himself with the music to Shakespeare's Tempest.
    Subsequent to this Tempest music, Sullivan published a formidable successon of serious compositions of steadily diminishing quality and success, which remained completely unknown outside England. Then, with Mr Gilbert, a skilful librettist, he set to work on the composition of comic operettas and has experienced repeated success. The Mikado has earned him a fortune and made of the plain Mr Sullivan the Sir Arthur of today. It is not surprising that this transformation of a heretofore serious composer should be appraised sourly by his colleagues. Nevertheless, Sullivan has accomplished something, if in a secondary genre, which no Englishman has ever accomplished before: to be melodious and amusing for an entire evening!