ii chord substitution

[pingu]

Sorry bout that ..... breath ......back On topic anyway

F is another common sub for D minor innit ?

|F | G7 | C

[JonR]

More on this please. I'm aware that TS is common with dominant seventh chords... min7th? What say you, Jake; bako?

Tritone subs don't work with min7th chords, but iim7s are often used in pairs with V7s.
So when Db7 subs for G7, Abm7 is often added before it, just as Dm7 belongs before G7.
IOW, Abm7 is not a direct sub for Dm7 (it couldn't be - it shares no notes!) - it's an indirect result of the tritone sub of the dom7.

Other variants of the ii chord in Dm7-G7-C (in case some of these have not already been mentioned):

F-G7-C (including Fmaj7 etc)
Dm7b5-G7-C (the G7 could be altered, as if borrowed from C minor)
Fm6-G7-C (Fm6 is an inversion of Dm7b5)
D7-G7-C
Ab7-G7-C
D7b5-G7-C (D7b5 is the same as Ab7b5, but if you add 9ths things diverge)

Of course, if you sub G7 too, other options are possible.

Dm7-Db7-C
Abm7-Db7-C
Fm7-Bb7-C ("backdoor" cadence)
...and maybe more

Of course, which of these are possible in any particular tune will depend on the melody. As JakeAcci says, you may be freer with subs in a solo, but I'd still be doubtful about using subs in a solo (or comping for a soloist) that wouldn't fit the melody. YMMV

Of course, a lot of these type of subs occur in turnarounds, where there is probably no melody, so anythng is possible!

[brwnhornet59]

LOL, I use FM7 as a rootless D-9 all day long.

As for the functionality of a tritone sub of a V chord, that is functional jazz harmony all day, and night, long.