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CDプレーヤー AVM OVATION CD8のPDF 取扱説明書をオンラインで閲覧またはダウンロードできます。AVM OVATION CD8 14 ページ。 Cd-player/dac/cd-drive

1. Basic informations

The case is fully made of aluminium. The audio-connectors are all gold plated to minimize electrical losses

and provide long lasting perfect contacts.

Drive and digitalaudio circuitry (CD8, CD8T) have each a power supply of their own: Two toroidal

transformers together with nearly 30.000µF of capacitance supply the power. All voltages are well regulated

to avoid hum and are additionally buffered by large capacitors directly in the circuitry where they are needed.

The disc is read by a drive especially made for CD. It can theoretically read CDs at 2 times the normal

speed. Thus the positioning of the laser pickup and the focus regulation can act very quick. So the drive

never comes to it's limits when reading audio CDs at normal speed. Besides normal audio compact discs the

drive can also read CDROMs and some CDRWs.

The drive is mounted in a capsule made of aluminum plates. This ensures optimal mechanical isolation of

the drive and reduces dramatically the influence of external vibrations.

The CD8T is equipped with a tube output stage. We use one double triode for each channel. The triodes are

operated fully balanced. They operate with grounded gates and are fed via the Cathodes. This circuit design

ensures very quick reaction without sound degrading feed back. The tubes are heated with about 2 Watts of

power. This ensures a very long life and constant characteristic over the whole lifetime.

Thanks to the wide operating range and the balanced operation mode the CD8T has a very good dynamic

performance and offers -in respect to the excellent CD8 - even a further step ahead in musical quality.

The tube output of the CD8T has it's own power supply. It uses a 25 VA toroidal transfomer and a

combination of capacitors and chokes for smoothing the DC voltage. The high voltage for the tubes is

generated by an additional power supply which is fed by a precisely regulated DC voltage. A 300 Hz sine

generator followed by a power stage and a toroidal transformer generate the regulated high voltage. This

power supply operates fully independent of the unstable mains voltage and thus the tubes can always

operate at a stable bias point.

1.5 Digital- / analogue conversion (CD8, CD8T)

The CD8 / CD8T are equipped with upsampling circuitry and highly precise a/d converters. The theory of

function will be described in the following text. If You are not interested in technical details, skip these

chapters and simply listen to the music. You will discover Your CD collection anew! And that is what we want

to achieve. Because application of new technologies is not just a gimmick but offers audible and measurable

advantages to the listener.

The quantity of information on a CD is defined by the audio format of 44,1 kHz sampling rate and 16 bits of resolution.

Additional informations (i.e. higher resolution or bandwith) cannot be created by any electronic circuitry playing back such

a CD. It is a fact that conventional d-/a converter systems do not fully reproduce the given information. This has several

reasons: Converting a digital signal to an analogue signal produces analogue noise. This is because the digital

(quantized) values which represent the signal are discrete with a very fine – but nevertheless limited - resolution.

Therefore exist slight deviations in respect to the analogue original signal which was continuous (means infinite

resolution). These deviations are random and cause an additional noise to the original signal when it is converted from

the digital domain to the analogue domain. This kind of noise is called quantization noise.