4/5 A Couple Special Moments in Beethoven's String Quartets

Bela Bartok in his later years used to carry around the sheet music of Beethoven's string quartets with him and never tired of showing his friends the amazing things he found in them.  So today in that spirit I'm concentrating on just a few favorite "moments" from B.'s string quartets.  Many times these are parts where things first really just seemed "weird" - but then seemed so right.

One that springs to mind immediately is the beginning of the recapitulation of the final movement of Opus 131. The first violin leaves the development with this long dramatic trill - and then keeps on going! I have no idea what this means from a harmony viewpoint, but it's a moment I look forward to every time I hear Op.131.  It's almost the reverse strategy of when the famous horn call comes too early in the Eroica's 1st movement recap.  But instead of being too early, this guy is too late!  You can hear what I'm talking about here at 2:35 (listen to the whole movement, but the link below just goes to the moment I'm highlighting):
Op. 131.6

Another great moment is at the end of Op.74, the Harp Quartet. We're well into the coda, things should be winding down - but B. suddenly cuts loose with a totally virtuosic 1st violin cadenza snaking through "tiptoe" pizzicato and one his most yearning themes. It's a true test of a quartet's communicative ability to have such a dynamic range of textures and still maintain a unified identity and message.  I put a link to that moment here at 39:57:
Op. 74

In Op. 18, No. 4 in C minor, the 4th movement, the theme is fast and witty and pauses at the end for a kind "breath".  However in later iterations Beethoven actually leaves out the rest and so there is a kind 2-note "chuckle" right after the phrase ends.  Here it begins at 2:02:
Op. 18, No. 4 M4

I talk about the Grosse Fuge all the time it seems, but here's one aspect I don't think I've written about before... After 15 minutes of nightmarish counterpoint and clashing phrases - Beethoven ends with an extremely "up" cadence. It's like a delicious glass of water after trekking thru a desert storm:
Grosse Fuge from 15:31

Finally, in Op.135, Movement 2 (Vivace) two cool things stand out for me - the sudden E flat half-note accents before the beginning of the 1st repeated section - clearly designed to give whiplash to any minuet fans - secondly the ostinato figure which repeats almost verbatim for 49 measures. This, to me is the first "hip-hop" loop in history.  ;)
String Quartet No. 16 in F major, Op. 135 2. Vivace
The Hagen Quartet 
The "ostinato" part starts at the 2 minute mark.

Opus 135 M2 ostinato figure