There are 3 types of triple tonguing.
The TTK in the Arban book, TKT,KTK (alternating ) in the James Burke “New Directions in Tonguing ” book and the rolling Ta Da Ga taught in Jacoby’s book “Jake’s Method”. I included all 3 types when I wrote my book.
TTK – TTK , TKT-KTK , & Ta Da Ga are different concepts of tongue useage. These are 3 prevalent triple tonguing concepts.
Whereas changing Tu Tu Ku into Ta Ta Ka , or Da Da Ga , or Di Di Gi is merely using different syllables. These 4 examples all fall under the Arban TTK .
For the Burke double-triple they would be Tu Ku Tu – Ku Tu Ku, Ta Ka Ta – Ka Ta Ka, Da Ga Da – Ga Da Ga and Di Gi Di – Gi Di Gi.
These represent lighter syllables and are quicker to use. The shorter the tongue has to move the faster the tonguing can be. I wrote them in order from heavest – slowest to lightest – quickest. The stroke involving the forward part of the tongue is Tu, Ta, Ti, Da and Di.
The stroke that involves the middle of the tongue is Ku, Ka, Ki, Ga and Gi.
There is No tongue stroke that should ever use the back of the tongue.
The rolling tongue needs to be Ta Da Ga – Ta Da Ga or Ti Di Gi.
So while there are 3 concepts there are alternate syllables to adjust for style of sound or speed.
The alternate syllables work on double tonguing as well Tu Ku , Ta Ka, Da Ga or Di Gi.
To work on speeding up tonguing skills use softer syllables like ta da or di. Also work with a metronome. Start at 1/16 notes @ 1/4 == 60 beats per minute. Every 15 – 20 seconds speed up 10 beats per minute. Make a note of the problem speeds and work on these. Do this with single, double and triple tonguing .