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MAGIC CD

CD designed to accelerate and intensify the burn-in of speakers and certain electronic devices. Jean Marie Reynaud first developed these signals for his own needs, in order to achieve more rapid stabilisation of the characteristics of the loudspeaker equipment.

Subsequently, he offered this recording to his dealer network, giving them the means for a faster and more thorough break-in of the speakers offered for listening, and finally decided to make it available to individuals, for their own needs.

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Ce CD contient des signaux conçus pour accélérer et intensifier le fonctionnement des enceintes et des composants de votre système HiFi, leur permettant d'atteindre plus rapidement leurs caractéristiques de qualité maximale.

MAGIC CD

Caution, the use of this lapping disc requires special precautions, in order not to damage the materials.

The use of this disc is the sole responsibility of the persons using it. This CD provides a powerful shortening of the break-in time of the equipment, which JMR loudspeakers should continue with continuously played music messages.

A successful break-in of JMR loudspeakers is achieved by both methods: music and break-in CD.

This CD has been made with care, it is intended to reduce very significantly the break-in time of the elements of a hi-fi system (about 10 times less time than with a music programme). It does not contain any music tracks. It should therefore be considered as a purely technical instrument and should only be used with high quality equipment.

On this disc, a narrow band random noise signal is recorded to simulate, at a reasonable noise level, the extreme conditions of use of the components of the system and in particular, those concerning all its mechanical parts (CD player and speakers). It must be used with the utmost care to avoid any incident to the various links in the chain (mainly the loudspeakers).

The narrow band of random noise recorded on this CD comes from a signal obtained by filtering the signal from a white noise generator fed by a series of modulators and filters. The resulting signal is 1.2 MHz of narrow band random noise with adjustable bandwidth at 10 Hz ,31.6 Hz ,100 Hz ,316 Hz and 1000 Hz. The centre frequency of each sample recorded on this disc has been chosen in a band between 2 Hz and 200 KHz.

1°/Narrow band of noise centred on 22 Hz:
> Range 1 = 10 Hz bandwidth
> Range 2 = 31.6 Hz bandwidth
> Range 3 = 100 Hz bandwidth
> Range 4 = 316 Hz bandwidth
> Range 5 = 1000 Hz bandwidth

These 5 ranges are particularly intended for the running-in of the woofer suspensions.

2°/ NARROW BAND OF ALEATED NOISE CENTERED ON 500 Hz :
> Range 6 = 100 Hz bandwidth
> Range 7 = 1000 Hz bandwidth

These two ranges stress the entire cone of the bass and midrange drivers, they ensure the running-in of this major element and stabilise the mechanical junction between the spider, the cone and the moving coil.

3°/ SMOOTH BAND OF ALEATED NOISE CENTERED ON 1500 Hz :
> Range 8 = 1000 Hz bandwidth

This range is particularly intended for the running-in of filter elements (high stresses on the mechanical resonances of chokes and capacitors).

4°/ 10KHz CENTERED ALEATOM NOISE BAND :
> Range 9 = 316 Hz bandwidth
> Range 10 = 1000 Hz bandwidth

These two ranges ensure optimal break-in of the suspension and tweeter diaphragms at very low noise levels.

5°/ PINK NOISE :
> Range 11 = This is white noise filtered to -3 dB per octave, covering the entire audible spectrum (20 Hz- 20 Khz) with constant energy.

It is particularly recommended for the breaking-in of modulation cables and can be used in this case,
the volume of the amplifier to zero. (e.g. transmission of the modulation between the CD and the amplifier).

PROCEDURE FOR USING THE DISC :

Imperative!… Before playing this disc set the volume of your amplifier to zero.

Play track 1:

Turn up the volume very gradually while watching the cones of your woofers, their displacement will quickly become significant and disordered despite a low noise level.

As soon as the slightest backlash (moving coil hitting the bottom of the air gap) appears, immediately reduce the volume.

Due to the randomness of the signal level the optimisation of this setting will be carried out over a period of time of about one minute.

Once the level has been adjusted, do not touch the amplifier settings when playing successive tracks on the disc.
Failure to do so may result in technical problems for which we cannot be held responsible.

Each new use of this disc, even partial, will involve the same adjustment procedure.

NOTE: For the running-in of the loudspeakers, the two loudspeakers can be connected in phase opposition and positioned face to face quite close to each other (about 30 cm), the noise generated will thus be reduced (acoustic short-circuit) and the running-in will take place just as effectively.