One of the basic skills needed to be a DJ is being able to seamlessly blend the end of one song over the beginning of the next, without making the transition sound awkward or jerky. In order to successfully “mashup” (mix music from other songs) in this way, you will need to find out the BPM (beats per minute) of each song. That way you will know if you need to raise or lower the tempo to make both play at the same speed. You can find out the BPM in the traditional way using your ears and a stopwatch, or use some simple program to help you.
Method 1 of 2: Calculate BPM Using Your Ear
Step 1. Identify the time signature of the song
In order to accurately calculate the BPM of a song, it is important to know how many beats exist within a bar (measure). While many songs feature 4 beats per measure, this is not always the case. For example, waltzes have 3 beats per measure. Listen to a repeating pattern that has constant beats to try to figure out the number of beats per measure.
- While you're counting, pay attention to the heavier beats. This will help you get an idea of when to start counting from 1 again (for example, in a 4/4 song, it will feel natural to count “
Step 1.-2-3-4”and so on.
One of the easiest ways to find out the time signature of a song is by looking at a sheet music. The time signature will appear at the beginning of the score in the form of a fraction, immediately after the key signature (for example, 4/4, 3/4, or 6/8). The top number represents the number of beats in each measure.
Step 2. Start playing the song and the stopwatch at the same time
Once you have an idea about the time signature of the song, you can easily calculate the beats per minute by counting the number of bars, or measures, that occur during one minute. To get started, play the song and start by syncing it to a stopwatch the moment you hear the first beat.
- To do this, you can use a simple hand-held stopwatch, watch the watch with a second hand, or use the stopwatch function on your phone.
- You may need to practice a few times before you get used to starting the song and the stopwatch at the same time.
Step 3. Make a mark for each full measure you hear within 30 seconds
As you listen to the song with the stopwatch running, make a mark on a piece of paper each time you hear the first beat of a new measure (the first beat). Stop counting and stop the timer when you reach 30 seconds.
You may end up stopping the stopwatch in the middle of a measure. For example, you might count 10 and a half bars. If this happens, write down on the paper that the final count was only half a measure
Step 4. Multiply the number of bars by the number of beats per measure
After turning off the stopwatch, count the number of measures you have heard. Multiply this number by the number of beats present in each measure to find the number of beats that occurred in the span of 30 seconds.
- For example, if you heard 12 bars and the song has 3 beats per measure, then the number of beats in a 30-second span will be 36.
- If you finished counting in the middle of a measure, add the beats you heard in the last measure to the total number of beats for the entire measures. For example, if the time signature is 4/4 and you heard 10 and a half bars, then you have heard 40 beats plus an additional 2, for a total of 42.
Step 5. Double the resulting number to give you the BPM
Now that you have calculated the number of beats in the span of 30 seconds, all you have to do is multiply the result by 2 to get the number of beats per minute. For example, if you've counted a total of 36 beats, the song's BPM will be 72.
You can also count the individual beats of the song if you prefer, but keep in mind that you will need to hear the constant beat of the song. For example, if you count every beat and motif you hear on the drum line of the song, you will end up counting an inordinate number of additional beats
Step 6. Match the rhythm of 2 songs at a time to practice
Even if 2 songs have the same overall time signature and BPM, the beats may not match exactly. This is particularly true when working with live and vinyl recordings rather than digital tracks. Start by choosing songs that you know well and that have the same (or similar) BPM, and listen to the playback until you find a good entry point to guide you as you sync songs.
- For example, maybe Track B has a strong drum beat on the first beat of each measure. Align the first beat of the measure of your choice with the first beat of another measure on track A.
- Focus on the entry point and listen to the moments where the beats of the 2 songs no longer line up due to tempo changes.
- From there you can decide the perfect place to transition from one song to the other.
- Most DJ programs have built-in features that make the process of matching beats easier. However, being able to match the rhythms using your ear will help you cope with tempo variations that the program cannot identify.
Method 2 of 2: Use Programs to Find BPM
Step 1. Find a beats per minute calculator and perform beats at each beat
There are a large number of applications, websites, and software packages that feature BPM calculators. In many cases, you will use the calculator by pressing a button while following the rhythm of the song. The calculator will then make the lump sum of the BPM based on the keystrokes you have made.
- Search the phrase "music BPM calculator" or "music BPM counter" online or in your app store to find a variety of intuitive app options.
- Some good options are applications such as BPM Tap and Tap Tempo, and online beat counters such as the one at Beatsperminuteonline.com.
Step 2. Try using a calculator that converts MP3 to BPM to automatically analyze the song
Some BPM counters are designed to analyze the BPM of a track automatically, without the need for you to enter a value. Do a search using terms such as "BPM analyzer" or "MP3 to BPM" online or in your app store.
Try using programs such as MixMeister BPM Analyzer or BeatGauge BPM Detector for iTunes
Keep in mind:
Although these analyzers are useful and easy to use, they are not always accurate. Some tracks are more difficult to analyze than others due to variations in tempo, so you may have to verify the results using an old-style manual beat count.
Step 3. Search the song in a BPM database
If you are getting frustrated with virtual solutions or your own attempts to count BPM, there is always the possibility that someone else has already done the work for you! There are several BPM databases available that provide data on many of the most popular songs. Look for the song title to see if a matching track appears. Some of the options include:
- The BPM value does not always remain constant throughout a song, particularly for songs that have a live drum track.
- It can be helpful to become familiar with the BPM settings that are common to the genre you are listening to. For example, most of the BPM in hip hop are between 88 and 112.
- Don't try to mix songs that have a difference greater than 5 BPM, and always go from a lower BPM to a higher BPM. It is possible to make an exception if you are starting a new set (set of songs) or have reached the "climax" of your current performance and need to calm the mood on the dance floor (or in the recording)
- Keep in mind that fusion is not the only way to mix 2 songs. You can also cut a track and then play the next, and that way you don't have to necessarily match the BPM.
- A great help for beginning DJs is to write the BPM of the songs on the record deck and then sort them according to their speed, going from slowest to fastest. That way, you will know what are probably the easiest tracks to mix.
- If you play a musical instrument, you probably already have a metronome. It is very common for metronomes to have a button that calculates the BPM based on the speed at which the button is repeatedly pressed. Press along with the song, and you can identify the BPM in seconds with a margin of human error of between 1 and 2 beats.