GB2392773A

GB2392773A - Digital turntable music deck

Info

Publication number: GB2392773A
Application number: GB0220378A
Authority: GB
Inventors: Kenneth John Bagnall
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-09-03
Filing date: 2002-09-03
Publication date: 2004-03-10
Also published as: GB0220378D0

Abstract

An audio controller has rotating controls 1, whose speed can be manually varied by an operator and whose speed of rotation affects the speed of playback from an audio source such as a CD player 11. The rotating control 1 is driven by a motor (fig 1, 3) and its speed is detected by a sensor (fig 1, 2). A pitch control 6 may adjust the rotational speed of the rotating control 1, and a switch (fig 1, 5) may stop the rotating controls, to facilitate effects such as scratching. A digital memory (fig 2, 9) may be used to store sound material for playback.

Description

1 2392773

DIGITAL TURNTABLE MUSIC DECK

The design enables the playing and mixing of digitally recorded music sources in real time with the physical control characteristics of an analogue twin turntable vinyl record deck.

Music has become a digital media. The recording and mixing process is now largely digital. Distribution media is largely digital. Already the Compact Disc (CD) is being replaced by the SACD, DVD,.wav files and MP3.

Many digital effects can easily be implemented using existing technology, it is possible to hold whole music tracks in digital memory and manipulate their playback speed, phase, pitch and other audio characteristics.

Yet club and radio presenters (D.J.s) still rely on analogue vinyl recordings to allow them to play and mix records. This mixing might be regarded as an art form in its own right.

The primary object of this design is to provide the subtle and tactile feedback available from manually controlling mechanical 'vinyl' decks in real time utilising spinning controls in lieu of turntable platters.

Unlike Jog / Shuttle type designs of control, the turntable control platters actually rotate in the same way as do vinyl record decks. This allows for subtle alterations in speed control using finger pressure and friction applied to the moving surface of the control platter. This is then translated by the design, to the playback speed of the audio sources.

The secondary purpose is to further enhance the facilities available to create effects which would not be possible with a vinyl record based deck.

There are 3 interconnected sections to the design: 1. Digital - Audio Source 2. Mechanical - Speed, Pitch (Beat) and Direction Input 3. Integration -processing & integration unit 1. Digital Audio Source - audio tracks are held in memory.

The digital audio streams are fed into the Processor / integrator.

There is scope here to control the audio characteristics e.g. Bass, Treble, Balance etc. of each source can be manipulated before it is processed.

This stage is capable of selecting and loading an entire source track or any sample from a source track, into memory. Source tracks can then be utilised in their entirety or a sample 'looped' continuously.

(I 2. Mechanical - turntables analogous to the technology currently found on vinyl turntable decks. These decks utilise rotating controls and can be run across a rotational speed range from zero upwards and can be controlled by finger pressure on the controls (platters) to either stall, stop or otherwise manually vary the control platter speed and direction of rotation.

Additionally, the operator could switch off the motors driving the control platters and rotate them wholly by hand.

Coupled to the turntables are speed sensors which monitor the control platter speed / direction of rotation and feed this into the digital processing system. Pitch', 'beat' or 'Beets per Minute (BPM)' controls are also provided to vary the running speed of each turntable control platter, analogous to those found on a vinyl based deck. Alternatively, these controls could produce offset signals which would also be fed into the digital processor.

3. Integration - integ.ates the feedback from the mechanical system speed sensors monitoring the turntable control platters and the 'Pitch' control offset settings, modifying and combing the digital audio sources.

The rate of playback of each audio source is determined proportionally by the feedback from the turntable control platter speed sensors and by the pitch' control offsets.

This control function for each audio track can be expressed mathematically: Rpb = VR (where the pitch control varies the motor speed) Rpb = VR + P (Where the pitch control produces an offset signal) Where: Rpb = Rate of Playback of the audio source VR = Rotational Velocity of control platter P = Offset output from 'Pitch' control Once this control function has been applied to each audio source, they can be mixed ready for output.

Finally, additional basic audio processing can be added i.e. overall sound levels, prior to outputting for further amplification / broadcast.

In conclusion, the primary feature of this design is applying the physical

characteristic of utilising a dual turntable design to control digital music sources.

Vinyl record decks not only provide a means of playing music, but in skilled hands, provide an immensely tactile means of controlling nuances of the music reproduction. This design emulates this control for digital audio media.

It is possible to alter the pitch or beat of the playback. Two music tracks can be matched for Beats per Minute (BPM) before being mixed on a mixer desk.

Scratching' also allows a wide range of effects to be created from a playing or even stationary disk.

Additional digital processing effects can be combined with the basic design which are not possible with purely analogue vinyl decks: When mixing tracks, one can be matched to the other for BPM (actual playback speed) but the audible musical pitch can be corrected back to normal. À Alternatively, the audible musical pitch of a track can be altered as if the track had been sped up or slowed down, while maintaining it's actual playback speed (BPM).

The design is outlined,n three accompanying drawings: Figure 1 shows the basic component parts of the audio controller Figure 2 expands on Figure 1 to show how audio source material would be coupled to the audio controller Figure 3 shows how the design might appear when assembled into one unit As shown in figure 1, each Control Platter 1 is driven by a motor 3 in order to rotate constantly. The speed of rotation can be further controlled by finger pressure on the controls (platters) to either stall, stop or otherwise manually vary the control platter speed and direction of rotation. Additionally, the operator could switch off the motors driving the control platters using switch 5 and rotate them wholly by hand.

Speed detectors 2 monitor the speed of each control platter 1 and provide a output signal. These detectors can be of any suitable design, optical, electromagnetic or mechanical.

Pitch' controls 6 adjust the speed of rotation of the control platters and / or provide an adjusting offset signal which can be combined with the detector 2 signal in circuit 7.

This output signal is fed into the Integrator 8. Here the playback rate of each audio source 9 is adjusted proportionately to the control signal from 7 prior to further processing and mixing to give a combined output, 10.

( In figure 2 this is expanded to show how this could be set up with digital audio sources. Digital audio is fed from sources 11. These could be CD, SACD, DVD,.wav files, mpg or any other form of digital audio source.

This audio source or any sample from the original source, is loaded into digital memory, 9.

The integrator circuits 8 then control the rate at which each audio source is played back proportionately to the output control signal at 7.

At this stage the audio is mixed and output, 10.

Further audio processing could also be carried out.

Figure 3 Demonstrates how a complete 'twin turntable' unit might appear.

The control platters 1 are seen on the top surface where an operator can apply finger pressure and friction to them.

The motor On/Off switches 5 and 'pitch' controls 6 are located close by.

Other track selection controls and audio controls which would operate on the memorised audio track output from memory 8 as it is played are shown.

The audio sources are show as CD/SACD/DVD/MP3 disks at 11 although any other audio source could be attached or fed into the unit.

Claims

1. An audio controller utilising a rotating control configured with a detector so that variations in the speed of rotation of the control itself vary the playback speed of an audio source.

2. An audio controller as claimed in claim 1 with an additional control to stop and start the rotation of the rotating control.

3. An audio controller as claimed in claim 1 or claim 2 with an additional control to adjust the speed of rotation of the rotating control.

4. An audio controller as claimed in claim 1 or claim 2 with an additional control to adjust the effect of the output from the rotating control.

5. An audio controller as claimed in claim 1 or claim 2 with additional control or controls to adjust the speed of rotation and adjust the effect of the output from the rotating control.

6. An audio controller as claimed in any preceding claim with two or more rotating controls, each with or without additional control as specified in claim 2, claim 3, claim 4 or claim 5, each controlling the playback speed of an audio source, where these audio sources are then mixed to give a combined output.

7. An audio controller as claimed in any preceding claim, coupled with one or more digital memories in which audio source material can be held for processing and playback.

8. An audio controller as claimed in any preceding claim, coupled with one or more controllers to select audio source tracks or parts of tracks for playback.

9. An audio controller as claimed in any preceding claim, coupled with one or more controllers to adjust audio playback characteristics such as, for example, Bass, Treble, Balance.