My most important rule, above all else, is to pick music that people enjoy dancing to. If people are dancing well and enjoying the milonga then the DJ is doing his/her job. Just like with the dance, I believe there are many guidelines but no hard rules. To every rule there is an exception, but the guidelines are there for a reason and have stood the test of time and they should be followed unless you have a good reason not to.
To build great tandas, a DJ needs a large collection of music. I have 6,000+ Tangos, 600+ Vals and 500+ Milongas. Now out of that collection there might only be 1,000 songs that I consider great for dancing. I say great because I have no interest in playing good songs, only great songs. I have my music organized in iTunes and have each song tagged with Title, Author, Year, Singer, Genre, Composer.
There are those that like pre-made tandas and on-the-fly tandas. I do both. I have many pre-made tandas by all the major orchestras that I know are great and have a wonderful flow from song to song. I also have what I call "Tanda Collections" these are groupings of between 5 and 15 songs that could all go together to make a great tanda. I could use them in any order and the flow should feel seemless.
I have playlists setup for each major orchestra which contains my pre-made 3 and/or 4 song tandas and my tanda collections. I also have seperate playlists for Vals, Milonga, Alternative Vals, Alternative Milonga, Alternative Electronic, and Guardia Viejo/Canyengue. The tandas in these playlists are already seperated by cortinas (see below), so that I can easily drop them into a live playlist as I DJ.
Building Great Traditional Tandas
Some basic guidelines:
I feel very strongly that all the songs in a tanda should work together and flow nicely from one song to the next. Here is a typical traditional tanda which conforms to the guidelines mentioned above:
As you can see, all of the songs are from the Orchestra of Carlos Di Sarli and are from a two year period from 1942 to 1944. All feature the singer, Alberto Podesta and they all have a very similar feeling, tempo and structure.
If the tempo (speed / beats per minute) change from song to song, I generally start with the slowest and end with the fastest. You could also do the opposite. I feel pretty strongly that the difference, in tempo, of the songs in a tanda should be minimal. The same goes for the style of songs. For instance, I would not mix a guardia vieja style tango, with a strong dropping beat, with a slow smooth, lyrical tango.
Of course, all of these guidelines can be broken, within reason. You can mix singers and play songs from very different periods, etc... BUT the songs should have a very similar feeling and tempo. No song should feel out of place. This takes a lot of time to figure out as a DJ and I can sometimes take hours just to build a single 4 song tanda.
Now Dance to the Tanda
I think one of the best ideas for building a good tanda is to try and dance to it. I usually test new tandas out near the beginning of the milonga and try dancing to them with a partner that I trust.
Playlist or On-the-Fly
People have very strong feelings about whether or not you should build a playlist ahead of time or if you should DJ on the fly. I generally start from an existing playlist and then make changes depending on my mood and what I feel the dancers at the Mionga will enjoy. I probably change about 50% of the playlist through the evening. I generally start with very traditional and easy to dance to music and then get progressively more challenging through the night. I usually use the format TTVTTM (2 Tango Tandas, 1 Vals Tanda, 2 Tango Tandas, 1 Milonga Tanda) and repeat.
The Larger Flow
I like to create a flow to the milonga by playing a variety of orchestras with different styles, moods and tempos. One of my pet peeves, is a milonga where all the songs are rhythmic songs from the 1930s. While I love those songs, I don't want to dance to them for 4+ hours. If I am sticking with the TTVTTM model, here is an example of what I try to do:
T - Medium Tempo - Rhythmic - Rodriguez
T - Fast Tempo - Rhythmic - d'Arienzo
T - Slow Tempo - Lyrical - Demare
T - Medium Tempo - Lyrical - Calo
Often, I start off with a medium or slow tempo tanda and then a faster tempo tanda leading into a Vals or Milonga tanda. Then after the Vals or Milonga tanda, I let people relax with a slower tempo set. BUT, you could do the opposite and play Pugliese or any really dramatic slow tanda, before a vals or milonga set. That way when the mood goes way down, it is immediately picked back up. Also, some dancers find dramatic songs challenging, so they may sit out and a vals or milonga set will get them back onto the dance floor. So, as you can see, there is no absolute formula and some surprises here and there can be good.
Also consider the style, theme and mood of the flow. For instance, I would not play a tanda of playful Donato tangos from the 1930s and then follow it with a tanda of elegant D'Sarli tangos from the 1950s. That is too big of a shift.
Don't just sit at the DJ booth, I feel strongly that DJs should dance. I often will think to myself, "If that DJ were dancing to this tanda, then they would surely see the problem with it and would never play it again." Make sure that if you do dance, that you inform your partner that you may need to leave the dancefloor quickly to make any adjustments.
Cortinas (Curtains) are short 30 to 45 second snippets of songs that are not meant for dancing. They are played between tandas so that the dancers know when a tanda is complete and they can return to their tables and search out new partners. Cortinas can be made from any type of music as long as they are not confused with Tango. At some Milongas in Buenos Aires, the DJs would somtimes play full length Salsa, Bachata or Rock and Roll songs for people to dance to between tandas, BUT not between EVERY Tanda. These long cortinas would be spaced throughout the evening.
Alternative Music Tandas
There is one catch-22 that you should know about alternative music. If you don't play any then some people will complain and if you do play it then some people will complain. Also, even if you play just 1 alternative set during a 4 hour milonga then you are going to be considered an alternative DJ forever! I consider alternative music to include non-tango songs that you could dance tango to, electronic tango and tango music that is generally not considered for dancing, such as Piazzolla. Someone recently told me that you could dance tango to anything. My response was, "Yes, but why would you." I explained that to me tango has a certain feeling and I want that feeling to exist in the music that I dance to. Of course, that feeling is very subjective but I think most dancers know it when they hear it.
There are some very good alternative songs that are excellent and fun for dancing tango to, but they need to be choosen very carefully and played at just the right time. There is no right and wrong answer to this but if I am playing a very slow Alternative Tanda then I usually follow it with a Vals or Milonga Tanda. The reason for this is that many people don't like alternative music and will not dance when it is played and if it is a slow set then it can bring the energy level of the Milonga way down. This is fine, but I play a Vals or Milonga after it to get everyone back on the floor and to pump the energy back up. Also, I try to make my alternative sets the same length as my traditional sets. If I am playing 3 song Traditional Tandas then I might only play 2 song Alternative Tandas, since alternative songs are often much longer and I don't want the non-alternative dancers to have to sit for too long.
Pugliese is NOT Alternative
I have been to several large festivals where I have not heard a single Pugliese tanda during a 5 hour milonga. If you go to any milonga in Buenos Aires, you will hear plenty of Pugliese and his music is very popular there. Sure, his music is more challenging to dance to, but you should not punish your good dancers. While Pugliese is not alternative most of the people who dislike alternative music also dislike Pugliese. So, if I am playing some alternative then I might play less Pugliese. I might also substitute a very slow and dramatic Di Sarli tanda for a Pugliese tanda.
Modern orchestras may sound great, but in general they are recording for a listening audience and not for dancers. There are some exceptions, of course, but you should be very careful with playing modern orchestras.
Music with Singers
I generally play music with about 80% with singers and 20% instrumentals. When I first started DJing, several people told me that you don't play music with singers and that there are dance orchestras, but no dance singers. Let me be clear, this was horrible advice and is ridiculous. These people have never been to Buenos Aires and obviously know very little about Tango dance music.
Most of the greatest songs for dancing have singing in them and some of the greatest orchestra singer combinations are staples of dancing: DiSarli/Rufino, D'Agostino/Vargas, De Angelis/Dante y Martel, Biagi/Falgas, Fresedo/Ray, Di Sarli/Podesta, Calo/Beron, Troilo/Fiorentino. To have a milonga without these combinations would be very poor DJing. The orchestras of Osvaldo Fresedo, Miguel Calo, Pedro Laurenz, Lucio Demare and Angel D'Agostino recorded very few instrumentals so it would be difficult to even build an instrumental tanda of these orchestras without choosing songs that really do not go together.
During the Golden Age, the singers were like another instrument in the band and blended in. In the late-1940s, you can hear a change in the music. Not as many people were dancing and the singers became the stars. The orchestras started playing more for listening than for dancing and became support for the singers. There are recordings where the singer is so loud that it is hard to hear the music behind them. This is not good music for dancers and should be avoided.
3 or 4 Song Tandas
There are excellent reasons for both. I like both 3 song and 4 song Tandas, but often go for 3 song Tandas because here in Atlanta we have many more women than men at Milongas. 3 song Tandas allow for more Tandas in an evening which means that people switch partners more often and more women get to dance. The main reason for 4 song Tandas is that you get to develop a stronger and stronger connection with your partner through the set.
As mentioned above, I feel very strongly that all the songs in a tanda should work together and flow nicely from one song to the next. To find 4 songs that flow as nicely as I would like requires a huge library of Tango music. I would rather hear a great 3 song tanda than a 4 song tanda where the last song is out in left field. I hear and feel this all the time. I am dancing with someone and we have found a great groove and then the 4th song comes on and it is totally different than the first 3 and it ruins the tanda. So, if you have a small collection then stick with the 3 song tandas, until you have a large enough of a collection to build solid 4 song tandas.
Don't mix 3 and 4 song tandas. This only confuses people, so stick to one or the other during a single milonga.
Regardless of the length of your tango tandas, most DJs play 3 song vals and milonga tandas.
Some factors which would cause me to definitely consider playing 4 song tandas would be: If most of the dancers at the Milonga were very experienced dancers and/or the Milonga was more than 4 hours in length. Also, if I was in a community which expected 4 song tandas.
Make Notes and Accept Criticism
During a Milonga, I have a notes program open and I make notes of tandas that might need volume adjusting, or one song seemed out of place or the tanda just simply did not work. Also, always be open to friendly criticism from the dancers.
Clint's Tanda Collections
Here is a link to my favorite Tanda Sets. These are the tandas of all of the main tango orchestras, that I have used for years when I DJ at milongas. Great tango DJs should also be very familiar with the Orchestras of the Golden Age of Tango.
Thanks for your time. These are just my opinions and I could be wrong.