secondary dominant confusion

[Jonnysaxc2]

am busy confusing myself over secondary dominants and wondered if there was a clearer explanation than I can find on google/ wikipedia etc!

my understanding is in eg D7 followed by G7 , the D7 is a secondary dominant?

arrived at because of the circle of fifths?

 

[jbtsax]

I like to think of it this way. V7 (dominant 7th on the fifth step of the scale) resolves to I in that key. If I then has a flatted 7th it then becomes the dominant 7th of the key a perfect 4th higher. It then becomes the secondary dominant.

Around your circle of 5ths it would then be:

C7 - F7 - Bb7 - Eb7 - Ab7 - Db7/C#7 - Gb7/F#7 - B7 - E7 - A7 - D7 - G7 which goes back to C where you started.

My understanding of a secondary dominant is when the I that a V7 resolves to in turn becomes I7 which is V7 in the new key it is then the "secondary dominant". In your example the G7 which follows the D7 is the secondary dominant.

Pete, of course, is the official expert and may have a better explanation that I have given.

 

[kevgermany]

Not sure if you know/found Dolmetsch.com, but it's an excellent reference for all things musical.

Good definition here(about a fitfth of the way down), which extends what jtbsax said:

http://www.dolmetsch.com/defss1a.htm

 

[Pete Thomas]

Pete, of course, is the official expert and may have a better explanation that I have given.

I'm not an expert, but I believe it's the other way round.

With D7-G7-C, D7 is the secondary dominant. Also known as V7 of V.

I learnt that a secondary dominate is when you get a dominant leading by a 5th down to another dominate type chord or a minor 7

C A7 Dm7 G7 | C

E7 Am7 D7 G7 | C

Em7 A7 D7 G7 | C

These are dominants that are secondary to the actual (primary?) dominant which forms the perfect V7 to I cadence, where I is a tonic chord (could be a triad, may 7 or 6)

The exception would be with blues, in which case a I or IV is often a dominate type chord (I1 or IV7) but the flat 7 is there just for blues coloration, not function.

See:

http://tamingthesaxophone.com/jazz-chord-progressions.html (half way down the page)

 

[aldevis]

Pete is quite right! I am not sure if the dominant of a subdominant is a secondary dominant (C A7 Dm7 G7 | C) but I guess it is only matter of names.

His last progression is almost the bridge of rhythm changes, that is a list of three secondary dominants an a dominant (E7/A7/D7/G7) .
D7/G7/C/C is quite a common ii/v/i on Clifford Brown's tunes, but you can hear that often Harold Land ignores the 3rd on the II7 and plays it as a normal subdominant.

 

[jbtsax]

I'm not an expert, but I believe it's the other way round.

With D7-G7-C, D7 is the secondary dominant. Also known as V7 of V.

In the example given resolving to a C tonic, you are correct. My thinking was in the key of G with D7 resolving to G7 rather than G taking it to the key of the subdominant as is common in going to the bridge of a song.

 

[Pete Thomas]

In the example given resolving to a C tonic, you are correct. My thinking was in the key of G with D7 resolving to G7 rather than G taking it to the key of the subdominant as is common in going to the bridge of a song.

My take on that is that it's an actual modulation to a new key. A secondary dominant can be thought of as a very very temporary modulation that never resolves, because the chord it goes to is not a tonic of either the home key or a new key. i.e. it goes instead to another dom7th (or in some cases m7) chord.

 

[Jonnysaxc2]

thank you all, all very helpful and useful. I will check out taming the saxophone First next time as well!
cheers

 

[jbtsax]

My take on that is that it's an actual modulation to a new key. A secondary dominant can be thought of as a very very temporary modulation that never resolves, because the chord it goes to is not a tonic of either the home key or a new key. i.e. it goes instead to another dom7th (or in some cases m7) chord.

I think we could agree that without knowing the actual key of the song and in which harmonic context the D7 to G7 change occurs, that we are both speculating as far as secondary dominance is concerned.

 

[Tenor Viol]

I'm not an expert, but I believe it's the other way round.

With D7-G7-C, D7 is the secondary dominant. Also known as V7 of V.

I learnt that a secondary dominate is when you get a dominant leading by a 5th down to another dominate type chord or a minor 7

C A7 Dm7 G7 | C

E7 Am7 D7 G7 | C

Em7 A7 D7 G7 | C

These are dominants that are secondary to the actual (primary?) dominant which forms the perfect V7 to I cadence, where I is a tonic chord (could be a triad, may 7 or 6)

The exception would be with blues, in which case a I or IV is often a dominate type chord (I1 or IV7) but the flat 7 is there just for blues coloration, not function.

See:

http://tamingthesaxophone.com/jazz-chord-progressions.html (half way down the page)

In my now very ancient O Level music, I vaguely remember that II of the original key is a secondary dominant (which aligns with the above as the dominant of the dominant).

 

[kevgermany]

I'm staying out of this, except to say that the Dolmetsch reference says that the term has a traditional/classical meaning, and it's meaning is modified/looser for use in jazz (my wording).

 

[Pete Thomas]

I think we could agree that without knowing the actual key of the song and in which harmonic context the D7 to G7 change occurs, that we are both speculating as far as secondary dominance is concerned.

In that case (not knowing a key or key centre), the D7 is definitely a secondary dominant, and yes, the G7 is speculatively a secondary domino (e.g. if we are in a key centre of F)