...interesting in detail but strange as a whole and even repugnant. The nature of the work consists-- to put it briefly--in applying Wagner's dramatic style to the symphony.
...listener is simply crushed under the sheer weight and monotony of this interminable lamentation.
...the immediate juxtaposition of dry schoolroom counterpoint with unbounded exaltation...we arrive at no definite impression and enjoy no artistic pleasure. Everything flows, without clarity and without order, wily-nilly into dismal longwindness. In each of the four movements, and most frequently in the first and third, there are interesting passages and flashes of genius--if only at all the rest were not there! It is out of the question that the future belongs to this muddled hangover style--which is no reason to regard the future with envy.
(Hanslick "Beautiful in Music")

...first, the absence of independent, separate vocal melodies, replaced by a kind of exalted recitative with the "endless melody: in the orchestra as the basis; second, the dissolution of all forms, not just the usual forms (arias, duets etc.) but of symmetry, of musical logic developed in accordance with laws; third, the exclusion of multiple-voiced pieces, of duets, trios, choruses, and finales. (Hanslick "Beautiful in Music", P154-155)

It consists of the intentional dissolution of every fixed form into a shapeless, sensually intoxicating resonance; the replacement of independent, articulate melody by vague melodization. (Hanslick "Beautiful in Music", P127)

A small motive begins, and, before it can develop into an actual melody or theme, it gets twisted, pinched, set higher or lower by continual modulation and enharmonization, enlarged and reduced, replaced or echoed, now by this instrument, now by other. (Hanslick "Beautiful in Music", P127)

The essential factor appears to be the orchestra, which weaves the organic music material from imaginatively spun threads. In no way does song dominate the orchestra accompaniment as the supreme will; it is rather the itself accompaniment, following with mere words the "endless melody" of the orchestra. For Wagner, who has declared that pleasure in the familiar terminable melody is "childish", this endless melody--a logical monstrosity-- is the panacea. (Hanslick "Beautiful in Music", P256)

..that the image of his dying mother should be used to excite Parsifal's sensual ecstasy. This mixture of the most holy feelings with the most unholy is the more offensive here because it is both unnecessary and unnatural. (Hanslick "Beautiful in Music", P219)

..deceit, prevarication, violence and animal sensuality (Hanslick "Beautiful in Music", P143)

Brahms recalls Beethoven's symphonic style not only in his individually spiritual and suprasensual expression, the beautiful breadth of his melodies, the daring and originality of his modulations, and his sense of polyphonic structure, but also--and above all--in the manly and noble seriousness of the whole
This strong ethical character of Beethoven's music, which is serious even in merriment, and betrays a soul dedicated to the eternal, is also decisively evident in Brahms. (Hanslick "Beautiful in Music", P137)