operating instructions
CD-players / DACs
OVATION CD8, CD 8T
CD-drive CD8D
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Dear customer,
thank You for purchasing this AVM product. You own now a versatile, excellent sounding hifi
component. Before enjoying music, please read this manual carefully. After that You will know how
to use Your new AVM component in the optimal way.
Sincerely Yours
Your AVM-Team
CAUTION: This unit contains a class 1 laser diode. Do not open. Invisible laser radiation can
damage Your eyes.
Laser diode Type : Ga-Al-As
Wavelength : 755 - 815 nm (@ 25 °C)
Output power : 0,7 mW max.
NOTE: Use only high quality cables for connection between the unit and the other components of
Your hifi set. We recommend cable lengths under 50 cm to avoid interferences which can affect the
reception of radio and TV tuners.
Declaration of conformity (for EC only)
We herewith confirm, that the unit to which this manual belongs fullfills the EC rules necessary to
obtain the sign
the necessary measurements were taken with positive results.
AVM Audio Video Manufaktur GmbH, Daimlerstraße 8, D-76316 Malsch
www.avm-audio.com, info@avm-audio.com
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Table of contents
Chapter page
Präamble 2
Table of contents 3
1. Basic informations 4
1.1 Mechanical construction 4
1.2 Power supply 4
1.3 The drive 4
1.4 Tube output stage CD8T 4
1.5 Digital- / analogue conversion 4
1.5.1 Quantization noise 4
1.5.2 Reduction of jitter 5
1.5.3 Filtering 5
1.5.4 Digital- / analogue conversion 5
2. Control elements and connectors 6
2.1 EVOLUTION CD8 overview 6
2.2 Pin configuration of connectors 6
2.3 Installation and cooling 7
2.4 Connection to mains 7
2.5 Connection of digital sources 7
2.6 Connection to an amplifier 7
2.7 Connection to digital recorders / external DACs 7
2.8 External remote control 7
3. Basic operation 8
3.1 Switching on / standby 8
3.2 Display 8
3.2.1 Display in CD player mode 8
3.2.2 Display in D/A converter mode (CD8, CD8T) 8
3.3 Insert / eject disc 8
3.4 Playable disc formats 9
3.5 Playing CDs 9
3.6 Repeat 9
3.7 Programming a playlist 9
3.8 Random play 10
3.9 Select input (CD8, CD8T) 10
3.10 Select filter (CD8, CD8T) 10
4. Personal setup 11
4.1 Set display brightness 11
4.2 IR control mode 11
4.3 Set autoplay 11
4.4 skip unused inputs (CD8, CD8T) 11
4.5 define input names (CD8, CD8T) 11
5. Reset 12
6. Remote control 12
7. Cleaning 12
8. If something doesn’t work 13
9. Conditions of warranty (EC only) 13
10. Technical data EVOLUTION CD8 14
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1. Basic informations
1.1 Mechanical construction
The case is fully made of aluminium. The audio-connectors are all gold plated to minimize electrical losses
and provide long lasting perfect contacts.
1.2 Power supply
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.
1.3 The drive
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.
1.4 Tube output stage CD8T
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.
1.5.1 Quantization noise
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.
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The characteristic of this noise is that it has an energy which depends on the resolution used to quantize the original
signal and which is continuously spread over the whole range of the sampling frequency bandwidth. It is obvious that this
noise can mask fine details of the originally recorded music.
For physical reasons it is not possible to avoid quantization noise. Also a reduction of the total noise energy is not
possible because the noise has been created when the signal was recorded. An elegant solution of this problem is to
increase sampling frequency when re-converting the signal from digital to analogue. The upsampling can increase
sampling frequency from 44,1 kHz up to 192 kHz.
When re-converting the upsampled signal the upsampling converter produces the same amount of noise energy as a
conventional converter.
The difference is that the noise energy is spread over a much broader frequency band. So the part of noise energy which
is within the audible spectrum decreases. You can imagine that like if You have a certain volume of fluid in a small glass.
If You fill the fluid in a glass which has much more diameter the quantity of fluid doesn’t change but the level will be lower
than in the small glass. In the same way the increasing of sampling frequency (called upsampling) broadens the noise
bandwidth and reduces the noise level. Most of the noise energy now is located in a frequency region beyond the audible
range and can easily be filtered out without affecting the music signal.
1.5.2 Reduction of jitter
Jitter means slight, varying deviations in the sampling frequency of a digital signal. These deviations come from
deviations in speed of the CD when it is played back (a natural effect, which can be reduced by mechanical means, but
never fully eliminated). They can additionally come from electronic circuits through which the signal must pass. When
such a signal is converted to analogue the samples arrive sometimes a little bit too early, sometimes a little bit too late at
the DAC. This leads to modulations in the analogue signal which can affect the quality of the reproduced music. The
spatial image is not precise, You cannot exactly locate the instruments, the sound is a bit roughened.
The solution for this problem is upsampling. Upsampling does not only mean multiplying of sampling frequency by a fixed
factor like it is done by the oversampling technique used in former times. Upsampling technique is more similar to
recording the original digital signal anew with a different sampling frequency (re-clocking). That means that the sampling
frequency of the original signal and the upsampled signal are fully independent of each other. Thus if the upsampling
converter has a stable jitter free clock the upsampled signal contains less jitter than the original digital signal.
The musical advantages of re-clocking are the second reason why the AVM CD8 / CD8T are equipped with a brandnew
upsampling circuitry and an additional stable oscillator circuit.
1.5.3 Filtering
If a digital signal is converted to analogue the analogue signal contains not only the original signal, but as well it’s mirror
image which lies in the frequency domain beyond one half of the sampling frequency. This mirror image (aliasing) can
cause unwanted interferences with the original signal and thus must be filtered out before passing the signal to the
amplifier.
If the original sampling rate of 44,1 kHz is used the filter slope must be positioned somewhat above 20 kHz and has to be
very sharp in order to let the audio signal pass and to eliminate the aliasing components. Such filters cause a large
phase deviation at the end of the pass band and have often also amplitude deviations. This leads to a harsh reproduction
of music and can also affect the localization of solo instruments and voices.
Upsampling to higher rates makes it possible to set the filter frequency far out of the audio signal range. For example at
192 kHz sampling rate the filter must take effect at 96 kHz. In this frequency region no music signal is present. Thus the
filter can theoretically not affect musical reproduction.
Anyhow the filter frequency and the gradient of the slope – even if out of normal audio range have some subtle, but
audible influence on the musical reproduction. Therefore the CD8 / CD8T offer You five different filter characteristics. So
you can choose your favorite filter upon your own taste.
1.5.4 Digital- / analogue conversion
The CD8 / CD8T use highly precise 24-bit converters to reproduce the analogue signal out of the digital data. The
converters output balanced signals. These signals are fed into a differential amplifier. The difference between the signals
is twice the audio signal (because one of the signals is inverted) and the difference of the inaccuracies of the converters.
As the two converters per channel are on the same chip, their inaccuracy is nearly the same and thus also nearly
eliminated by the differential amplifier.
The second advantage of this differential technique is that the (very low) individual noise coming from the converters is
reduced by 3 dBs.
The result is a clearly audible advantage in dynamic of the music signal and an audibly improved reproduction of the
finest details.
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