Table of Contents:
- What is D'Groove
- What is a turntable?
- Why are turntables so popular?
- Features of the D'Groove System
- Haptics with D'Groove
- How does it work?
- How does it compare with Finalscratch
- Project history journal
- Contact information

What is D'Groove

D'Groove (Digital Groove) is the world's first digital haptic turntable. It controls the playback rate and position of digital music (MP3's, WAVs, CDs). It also uses "haptics" to provide information about the music through the sense of touch.

What is a Turntable?

This is the main tool for any "respectable" DJ. It is the voice of the DJ, the hands of the DJ and source of the music. Vinyl records are placed on the main platter of the turntable and a needle arm (containing a needle) is placed on the records. This needle fits into the grooves of the records and reads the musical information stored there. Of course, DJs can use other methods for playing music...such as CDs or MP3s but to most DJs, there is a certain style, hands-on feeling or flare about mixing and spinning round pieces of vinyl. For years, Technics, has made the standard 1200 series turntable (as shown above). This deck is so popular that almost every turntable company has copied the basic design in an attempt to meet the demands.

Why Are Turntables So Popular?

• Direct Hands-on Approach to the Music.
  You're hands are directly touching the source of the music. There is an immediate response to you touching the record and its effect on the music. By applying enough pressure on the record you can stop it from rotating, thus stopping the music. You can speed up or slow down the record by either pushing it ahead or applying pressure to slow it down.
• Scratching a Record.
  By pushing a record back and forth, a DJ can create a unique scratching sound which serves as an instrument in a DJ mix.
• Visual representation of the Music.
  Each record that is played has grooves. The grooves on the record are dense in areas where there is lots of sound happening and less dense when there are fewer sounds happening. Thus, a DJ can "see" the musical track and can anticipate what is going to happen as the track progresses.
• Pitch Control of the Music
  On the right side of the turntable shown above is a slider which controls the pitch and tempo of the record. By sliding this slider up or down, the DJ can speed up or slow down the pitch and speed of the record.
• Performance Aspect
  People enjoy the thrill of watching a vinyl DJ do his or her work. There is an element of visual entertainment in watching a DJ mix and spin records on a turntable.
• Availability of Music
  Record companies know that club DJs use turntables. These companies also know that it is the club DJs who first introduce tracks to an audience so in an attempt to sell and promote tracks to an audience, record companies produce special remixes of various tracks and release them only on vinyl. From the point of view of the DJ, there are loads of tracks that are only available on vinyl and so a turntable comes in handy for playing those tracks.

D'Groove - The Digital Turntable Project

In an attempt to preserve the finer qualities of a turntable, this project aims to add a digital feature to the turntable so that DJs can play digital music while maintaining the feel and performance aspects of a traditional turntable. By moving to a digital realm, we can still keep the desired aspects of the original turntable and add a handfull of additional features.

This project is still on going so we are constantly adding and testing out new features.

Features of the D'Groove System

• Access to Massive Music Library
  There is an immense amount of music available in a digital format. CDs and MP3s are the most popular form of digital music. Buying music on a CD is often less expensive than on vinyl and MP3s are often very cheap. Thus, the costs of maintaining a music library are less when moving to a digital format. As CDs are the most popular form for storing musical information, DJs will now have access to all sorts of music that was previously unavailable when working with just vinyl. However, as mentioned above, many new songs are only available on vinyl. We forsee this changing as DJs move into a digital environment. Vinyl only exists because it still provides the best means of controlling music. When we gain fine control of digital music, we no longer need to depend on vinyl.
  
• Mobility of Music
  Most traveling DJs find it difficult to travel with a huge crate of records which can weigh a heavy amount. Digital music can be stored on much smaller mediums and thus is easier for traveling. The size of your hardrive is now the limiting factor in how many tracks you can bring to a party.
  
• Visualization of Music
  When using vinyl, a DJ can gain knowledge about the music from looking at the grooves of the track. In a digital format, we can not only look at virtual grooves, we can color code various parts of the track, provide valuable timing information, display frequency/time graphs and study a Fourier analysis of a sound. We can provide a much better and more useful visualization of the music when analysing it in digital format.
  
• Beatmatching Aid in Software
  Software can aid in the matching of beats from separate turntables. This is one of the main tasks of the modern DJ. When the beats of separate tracks are in synchronisity, the DJ can fade from one to another, thus creating a mix. If we have software to aid in the beat matching, then the DJ will have more time to be creative and add effects to their music. It is felt that beat matching is a technicality that DJ's must overcome before they can begin to be creative. The creative process of creating music begin once the technical aspects of DJing are taken care of.
  
• Beatmatching Aid in Hardware
  D'Groove maintains a smart method of providing visual beatmatching cues through the platter. The intelligent rotation of the platter helps the DJ predict when the next beat will occur.
  
• Digital Sound Effects
  Without having to purchase a separate effects unit, a DJ could add sound effects such as distortion, reverb, delay, wah and many others to his/her music. This is as simple as using a plugin to alter the sound.
  
• Speed/Tempo Control
  The speed or tempo of a track could be altered independently from the pitch. In most turntables, DJs have the option of altering this to only ±8% of the preset speed. In this case, the pitch is also affected. In a digital format, this parameter could be altered to allow the DJ to have a much wider range of speeds while maintaining a certain amount of precision.
  
• Pitch Control
  The pitch of a track can be altered independently from the speed or tempo. In most turntables, DJs have the option of altering this to only ±8% of the preset pitch. In this case, the speed or tempo is also affected. In a digital format, this parameter can be altered to allow the DJ to have a much wider range of pitches.
  
• Sampling
  Also, without the addition of an extra unit, the DJ could create and use samples taken from the digital music. This common technique involves taking smaller sound bites (samples) and placing them in a track or looping them to create a backbone for a track. This can be done quite easily and precisely in a digital format. You could record any sound on your computer and then start scratching it or adding it to a mix.
  
• Scratching
  By monitoring the speed of the platter and/or "a specially encoded" record on the platter, we can implement scratching sounds as done in the analog world. The same feeling as found when using a traditional turntable can be maintained. "But it sounds digital", you say! Not to worry, my friend, we can solve that problem too. We can even create new scratch sounds that cannot be done with an analog turntable.
  
• Motion Recording
  D'Groove can record the physical motions of the turntable and then play them back. This motion could be mapped to a different piece of music so you can try a scratch out on one song and then see how it sounds with another song.
  
• Performance Aspect
  The D'Groove system still has a similar look and feel of a regular turntable. Once complete, it will be installed in a real turntable thus giving the proper appearance. Hey, that's half the battle in the DJ world.
  
• Intelligent Turntable
  In the D'Groove system, the turntable has two way communication with the computer system that drives the application. Thus, the turntable can be controlled from the computer and can be given certain information about the music it is controlling. Thus we can make the turntable act in various ways depending on what is needed in terms of the music. By making a smarter turntable, we can make smarter music.

Haptics with D'Groove

Haptics refers to "getting information through the sense of touch". A good example of haptics is when your cellphone buzzes to tell you that you have a call. It's telling you something through your sense of touch. A bad example of haptics is using your mouse and keyboard to control a computer. You're controlling the computer but it's not giving you any information through the sense of touch.

D'Groove boasts several haptic modes

• Bump Mode
  Bump mode is an exploratory mode. In bump mode the turntable does not rotate on its own. Instead the DJ moves the platter with his/her hand and the music plays accordingly. As the DJ rotates the platter, he/she will feel bumps at various places around the platter. Each bump corresponds to a beat in the song. Thus, you can "feel" the beats in the song. If you want to go 4 beats into the future, just rotate until you've felt 4 bumps. Bumps parameters such as size and duration can be changed to relay more detailed information about the beats.
  
• Breakdown Mode
  Breakdown mode is an exploratory mode. In breakdown mode the turntable does not rotate on its own. Instead the DJ moves the platter with his/her hand and the music plays accordingly. As the DJ rotates the platter, he/she will feel various changes in resistance. When the song is full of energy, the platter will be harder to move and it will feel like you are wading through lots of heavy music. When a break (less musical energy) occurs in the song, the DJ will feel much less resistance. So to find the first break in a song, simply rotate the platter until you feel a drop in the amount of resistance. This is useful for locating musical events.
  
• Spring Mode
  Spring mode was developed with the scratch DJ in mind. In spring mode, the turntable acts like a spring. It has a home position that it tries to maintain. A force from the DJ in one direction will cause the motor to respond with a force in the opposite direction, causing the turntable to want to head back to its home position. New scratch techniques can be created as the DJ "plucks" at the turntable. We can also alter the parameters of the spring effect.
  

How Does it Work?

D'Groove is still being implemented but we have enough working to show off a bit. We have implemented one turntable but the real system would involve two turntable devices attached to a computer. We have two-way communication between the turntable and the computer so all devices can talk to each other. Our turntable is intelligent in that it knows certain information about the music it is controlling and thus can act appropriately. The speed and direction of the turntable controls the speed and direction of an MP3 (or any other audio file) on the computer. So the music comes from the computer but is being controlled by the turntable. The system is run in real time to acheive a low latency and we are working on improving some problems associated with beat matching and cuing songs. We are also looking into making new scratch sounds like scratching a needle on glass or even something like stone on stone as opposed to a needle on vinyl.

The left image shows the very first prototype of one of the D'Groove turntable devices. No it's not actually a turntable. It's just a turntable-like motor (direct drive) and we attach it to our computer. Working with smaller components such as this takes up a lot less space in our lab and allows us to work on the important details.

The right image is our current prototype. As you can see, it has evolved quite a bit from the first model. This turntable has a much stronger motor and we've include crosshairs on the platter to help with beatmatching. As the red line crosses the north, east, south and west points, a beat plays in the song. Thus one revolution of the platter is the same as playing 4 beats in the song. This makes a much stronger link between the movements of the turntable and the playback of the song.

D'Groove is a Master's Thesis combining elements of Computer Science and Electrical Engineering. It is ongoing work and we hope to demonstrate some of the uses of turntables as input devices for digital media.

How Does it Compare to Finalscratch?

For anyone who is doing research in this area, I'm sure you have by now heard of FinalSratch. I had the pleasure to play with the first prototype of the system many months ago and I'd like to congratulate the N2IT team for their good work (Yeah it was made by N2IT and then bought by Stanton). D'Groove has a similar goal as FinalScratch - access to the digital domain. However, D'Groove has many differences. The two applications work in a very different manner. The most important difference is that D'Groove supports two-way communication between the computer and the physical devices involved. With Finalscratch, the movements of the turntable tell the computer what to do with the music. This is true with D'Groove as well but the computer can also tell the turntable how to move. Thus, D'Groove supplies musical information to the turntable so it can act in ways that are more useful to DJs.

Project History Journal

Contact

Since I've started this, I've received lots of great feedback from others who are working in this area. If any of this project sounds interesting to you, then I'd like to hear from you too. I need input from DJs and musicians as to what they want in a DJ system. Do you have any thoughts on what you like about turntables? Would you like to learn more about this project and how it is progressing? Send me some email as I just love talking about this stuff!