What key or mode do you think this in?

AntiA and I disagree on the tonality of this piece by Bach. I will agree with AntiA that I go too far to say Bach suggests Lydian w/ the B natural (it serves as a neighbor tone to the C and a leading tone to the dominant of F minor). AntiA says this is in C minor.

Ok, here is the piece -

My reasons are:

1) The introduction of D flat in measure 6 suggests the relative major of F minor - A flat major. If this were in C minor - the fugue then is quickly moving to the flat II, neapolitan - Most Baroque fugues do not go into the Neapolitan area so soon in a piece and when it happens it is rather a big deal. In the example below where the Neapolitan 6th makes its appearance the dominant of G minor is established by the pedal solo and then we have a great Neapolitan 6th chord that serves as a deceptive cadence. The C then serves as the root of a V2 chord which then moves to vii0/V, V and then i, ending on a Picardy third.

2) You will find the Bach notates the key signature of a piece in F minor with three flats once in awhile .

3) Read the notes to the left for this you tube post of JFK Fischer's own collection of preludes and fugues. This was one of the the models Bach used for his Prelude and Fugues and the usual accidentals used - note how C minor avoids D flat and uses instead F# - which is in keeping with BWV 689 where the fourth is raised, although Fischer does not do this in his Fminor piece.

4) Finally, if you look and hear the cadential points in 689 they are mostly i iv and V and the ending being a I (eg Picardy third). The I ending in F minor seems to be favored by Bach as heard in from his Prelude and Fugues from WTC such as this one:

Egad writing this makes me realize how much Bach I have been studying all these years!

c minor

I agree...just look at the key signature. I know it might be confusing in some spots, but oh well...we all know how that happens!

And it is being played old style, which is a semitone flat, just to make sure nobody gets TOTALLY confused ;)

Okay, so CompO and I don't -completely- disagree on the key of this prelude. I took a closer look.

The first note of the subject is an F followed by C, C, B nat, and C. Since there is no contrapuntal texture in this first bar to give us any other indications of harmony, we can at least view these first two bars as an implied harmonic progression of I-V-I (bars 1 and 2). We could say the next two bars are a reverse of this progression with the F and Ab in the downbeat of bar 3 being 4-3 and 6-5 suspensions - so I would argue the following measures are a V-I answer to the opening subject. This gets pretty hairy-cary in bar 4, because we go to implied harmonies of Eb, G, then C minor in bar 5. This would be a III-V-I, which could easily be I-V-I if the C was on any downbeat of bar 3. It wasn't though.

As far as the key signature of C minor, it's interesting to point out how much easier it is to use that key signature if you wanted to imply F melodic minor because there would be no need for the D nat accidental throughout, nor would there be a need for a key change to C minor everytime it happens. So, I'm almost leaning toward this fugue being in the key of F melodic minor simply based on these opening measures. I haven't really reviewed any of CompO's other points.

I'm not a theorist, either. Analysis at this level of specificity creates the risk of applying certainty to something that is hardly certain. It's music. There's nothing -right- or -wrong- in the way we understand music at THAT level of review. I've seen people literally almost come to blows over how the Tristan chord in the opening measures of the prelude resolves. It's ambiguous, just as this is ambiguous. I don't see the point in trying to be "certain" about something we can't be certain about. All we're really doing in that exercise is rationalizing our analytical method, which we more often than not feel -must be- a right or wrong, black and white kind of thing. Analysis of music is nothing of the sort for me. If it walks, talks, and quacks like a duck, I really don't care about how many hair follicles a duck's feathers should have to determine whether or not it is, indeed, a duck.

If that makes any sense...

AntiA - you make sense. This discussion does run the risk of splitting hairs.

Again for those that say C minor according to the key signature, how do you explain the final cadence on IV if in c minor?

Isn't it obvious to you why he ended the piece this way? Look at the opening, he starts with the f.

My first and only thought is F minor (it begins and ends in F, and in the Baroque that's a fairly obvious marker). It is not unusual for Bach to use one accidental less than today's standard to notate a minor mode piece. He was probably thinking in F dorian.

I had thought F minor as well.. but the use of the B natural throughout the work wouldn't fit within F minor. I think the F minor start and finish is meant to confuse the listener, to be honest. Or it could be an alteration of the fugue subject to fit with concurrent rules of fugal writing at the time.

Wish I had the score in front of me... Is that the only F# in the work (you can see it around 3:04 of the video)?

Black Orpheus has hit it on the nail F dorian was what Bach was thinking as the fugue is based on part of a chorale by Luther which was originally D dorian. Yet the chorale introduces a C# early on - that is why in the fugal subject transposed to F we have a B natural.

SO the notes of the original chorale tune the fugal subject and other material is is based on (note assume movement less than a fourth unless indicated in parenthesis) -

D (up a fifth to) A A G# A (down a fifth) D F F F E D/ F F F D F G A G F E D/ F F F D F G A G F/ (UP a fifth to) C D C (down a fourth to) AGFGAGFED.

But it is in F minor. The F# appears I think twice measure 18 and 43 -- usually when in the C minor area - V/V V i or later an augmented 6th chord to cadential 6/4 in C minor.

Particularly instructive is to see what materials or contours he incorporated and how into the subject, countersubject and sequences - for example notice he develops a sequential countersubject by inverting the FGAGF motive from the original chorale tune.

See as you investigate the piece further you see and hear it is a slippery little fugue (even if it starts and end in the tonic). The ClavierUbung has some wonderful pieces like this. I recommend the Barenreiter edition as it provides in full the chorale tunes most of the pieces are based upon.

Hm, guys. A 5th jump at the very beginning to F and the key sig is enough to tell you that the thing is in F minor, what was the problem? As for the mode, it's neither here nor there since Bach didn't adhere to modality exactly and it's hard to transplant analysis systems like that (if not totally meaningless.)

(Oh yeah, good'ol baroque practice tells us that 5th jumps in the subject are used to establish a key; from that alone you can infer TONS of things. Woop~)

SSC is right. Remember that in baroque, the composers often left off the last flat we would expect from the key signature.

The piece begins and ends in F and clearly uses C as the dominant several times. I'm sure there are some interesting modal inflections, but I don't have time to analyse it.

Agreed SSC and Daniel ... my point about the chorale tune is more to see how Bach used the raw material for his fugue. To me that is quite interesting.

THe thread also is a bit of lesson to not depend 100% on the key signature - especially to the point of ignoring the salient indicators of the piece's tonality.

Anyway, it generated some nice thoughtful comments. Yeah!

Maybe it's a lesson in not being sucked in to analytical discussions when you don't have time to analyze the piece.

haha, i don't care what key. the guy is so brilliant, my interest is how the hell the melody can move so fluently from the higher voices to middle and upper without confusing the listener. just amazing. sorry to be naggy.

Hm. Don't have the background for an analysis, but the feel I have throughout the piece is f minor. In my opinion the misleading is given by the subject, that is so short and modulates very soon to prepare the answer.

Review carefully the prior posts for the reasons why you are correct.

This prelude is definitely in F minor. The old-style minus-one-flat-for-minor is what's confuzzleing people. Key signatures mean nothing to the *actual* tonality, they're just a convenience to not write accidentals for every time there's an Ab.

agree on f. Just had to say love this prelude :)

for the same melody and an even lovely prelude see http://www.youtube.com/watch?v=HFd8VBV5eCg.

Note the insame chromatic lines half-way. starting chromatic lines at 2:04. climax at 2:51. Must see!

Yes I love that prelude too - that is why I posted it and promoted the discussion.