When we are talking about ordinary tango, 4/4, there is a shared understanding for the usual steps, where they should be placed and how they relate to the music and the notes! The following variations are known even if there is a lot of frustration because of the names of them. In the illustrations below you find all the four beats, accents, for a 4/4 tango written as B1, B2, B3 and B4. The accents we use for ours steps will be marked with red color.
We take only one step during a whole measure.
You can take a step extremly slowly or decorate during the *waiting time*.
We step on B1 and B3.
You can do it like B1_B2_B3 or B1_B3_B4 as illustrated below!
These are the fastest basic steps in tango in two variations.
These are the names for basic speeds for tango steps but there is a lot of situations when it goes faster and those steps are called traspie. There is traspies in tango, but it happens far more often in milonga. The ordinary milonga steps are double as fast as for tango. When you in tango take two steps you are putting down your feet four times in milonga.(*) So basic milonga steps are as double-time steps in tango, continuously. It means that if you do some kind of double-time steps in milonga they end up in traspie group; they are double-double-time in tango.
To review the traspie possibilities in milonga we need to understand the structure of milonga first. It has a basic rhythm with two accents, two beats marked below as B1 and B2, and the measure is 2/4. Above this basic rythm we have a fixed rhythmic pattern often called habanera and here marked by H1, H2, H3 and H4. Pay attention for the differences in duration for habanera accents. The basic rhythm and habanera are sounding together at B1/H1 and B2/H3 but H2 and H4 are sounding alone. Please check here! The red ones are for your steps!
The explanation below is valid for all milongas but it is not so easy to hear or produce them during a fast milonga. So try them while listening to a slow milonga, for example Milonga Sentimental.
Traspie variation 1
We step on both beats in this milonga measure, B1 and B2, as well as H4. This could be seen as a double-time step in milonga - but keep in mind that it is double-doble-time compared to tango steps above.
You can dance this in many different ways but to start with use rock step. B1 right foot forward, B2 left foot forward, H4 rockstep backward, B1 forward
Traspie variation 2
Here also we step on both beats, B1 and B2, as well as on c. There is no clear accent for c and if you have a trained ear you can get a feeling to step offbeat.This could also be seen as a double-time step in milonga/double-double-time step in tango as the case was for Traspie variation 1 above.
Traspie variation 3
This traspie is fundamentally different compared to the ones above because it introduces a double-double-doubel-time step compared to tangons double-time step. We use the both basic beats B1 and B2 but this time we step even on the second habanera accent H2.
We can use the rockstep here too but the time space is so short that there is hardly time to rock but only replace the foot before us some centimeter further forward. This gives me a clear feeling of stumbling.
Here you have a link to Milonga Sentimental as a guitar version with sheet music.
Measure I Measure II