THIS HAS BEEN SUPERSEDED BY
HD-990
(You supply and will also upgrade)
But if you have one, get a Quote for a Special
One-Off Price. Contact.
AUD S1250 - for Full Conversion
(See
optional RFI Treatment below)
This is the player I did not expect to do, a single
format CD Player. But events unfolded and this is an extraordinary player.
When
David met Goliath, it
wasn't reputation or size that mattered. This new dedicated CD Player has the potential
to turn expectations up-side-down. Harman Kardon based, this JLTi CD Player does
CD only format. With your regular CDs,
you will find that you have a music library ready to be listened to all
over again. Irrespective of price, we do not know of any other player that
does CDs better than this machine!
230-240V Model
2 Cryoed RCA
Outputs
JLTi Dedicated CD Player - Features our new type of
I/V Converter.
There is still a market for digital players that are
dedicated to playing CDs only. Many are convinced that players designed
for this single task are better than players that have to play many
formats.
For whatever reason, this new JLTi player does CDs as good or better than
any digital player we know of at any price. But to achieve this
level of performance we had to come up with a new solution to an age old
problem, converting 'current' from the DAC to usable 'voltage.' All
earlier JLTi Players have all used voltage DACs, and we avoided the
alternative current DACs used in many up-market players. We
now have finally cracked this thorny problem and we are very excited by the results. Truly
State-of-the-Art solution can now be applied to current DACs.
These so-called I/V Converters are often the real blame for what has been
termed 'digital sound' or even 'digititis' - as if it was some kind of
decease or affliction.
The problem is caused by the great leading edge and high level of noise
that the post-DAC audio circuitry has to deal with. At very high frequencies,
the usual audio circuits (operational amplifiers) have poor headroom and
this leads to over-loading. They are simply overwhelmed. When the circuit
is overloaded at high frequencies, it is overloaded, period. The frequency
matter not. When the exposure exceeds the capability
of the audio circuit, it causes slew rate induced distortion. This
is the weakness of I/V Converters. It is digital sound.
We had to come up with a bomb-proof audio circuit, one that has a huge
bandwidth, low noise, low distortion and no negative feedback. So what?
Aren't others doing just that? Mostly they are not and alternative
solutions have been improvements rather than solutions. We need to think
outside the square, and this is our forté.
The conventional I/V Converter is know as an 'Active' converter. It is
done by using an opamp (either IC or discrete) and huge amount of feedback
to create a 'Virtual Earth' which emulates a dead short to be seen by the
output of the DAC. If you think in voltage terms this does not make sense.
But I assure you, when the output is 'current' then this is actually very
logical. But while it was found that this 'earth' should have no signal
(if it was a real short there wouldn't be) when in fact there was always
some signal when observed via an oscilloscope. So what is going on? A
Virtual Earth is clearly not perfect and in reality some signal shows that
it must be slightly above zero Ohms. Not a dead short.
So now lateral thinking comes into play: If indeed a small signal is
considered acceptable, then why not use 'Passive' conversion? Now the use
of Passive Converter is not knew and we do not pretend anything else. So
what is new? Read on please.
The DAC used in our vehicle, the Harman Kardon HD970, is the Analog
Devices flagship converter (why it is used in this reasonably priced
player, don't worry, just be thankful), the AD1955. Now Analog Devices themselves do
not recommend Passive conversion as the AD1955's output has AC current (the
audio signal), also DC current (the offset current) and voltage (the
voltage offset). We have to cope with all this and more. Their reaction
was to simplify it and insist on Active conversion. It is simple to
implement. But the sound is inherently flawed.
Solution: Aside from coping with the offset voltage and
current, the actual AC audio signal can be formed across a differential
floating pair of resistors. The floating takes care of the voltage offset
and the remaining offset current can now be equalised from a positive
voltage source. The differential current across a very Low Z (impedance)
means we can emulate a similar signal and impedance condition to that of a
Moving Coil Phono Cartridge.
Hey, here is a good idea! We already have a leading edge Moving Phono Preamp, the
JLTi Phono. So now we can use Phono Preamp technology sans RIAA Equalisation
and bring the output voltage up to the industry standard 2 Volt RMS. This technology fits the bill perfectly; super large bandwidth, low noise,
no feedback and completely slew rate induced distortion free. Once this
occurred to us we just knew we had cracked the problem even before
building the first proto-type. The logic was simply irresistible and the
first sample brought a smile to our face - finally after many years, this
was it!
So the player's entire post-DAC circuit has been
replaced along with its new SuperReg power supplies. Only a two-pole
filter is used that is entirely passive.
Features:
-
The
Reference Clock
-
Custom Output Stage
-
Back-EMF Noise Reduction
The “Reference Clock”
is not just another clock. A new and
key design by our team from Vacuum State (www.vacuumstate.com)
and used by permission. Not just of the highest
quality but also incorporates a unique power supply, with extraordinary
low frequency bandwidth and has rock like stability. Our finding that Low
Frequency jitter is sonically more serious is not in itself unique, but
that jitter down to sub-One Hertz is critical and usually noise in the
power supply at ultra-low frequencies is far more serious than previously
thought. Only by actively seeking and finding a solution (because the
problem is largely unmeasurable) will it then
become apparent by listening. LF noise performance in the Reference Clock
easily surpasses even batteries.
Our new I/V Converter,
no negative feedback, ultra-high non opamp circuit with full SuperReg
power supply. Rifa Evox PPS output capacitors - outperforms the usual
expensive audiophile grade types. Cryoed silver clad wire and output RCA
Socket replaced with cryoed treated type.
Major reduction of
back-EMF noise in digital circuits. Grossly
overlooked and underestimated problem, often not
fully understood until the results are heard. Even the most expensive
players on the market are inadequate, so much so that any player
can be improved by just tackling this problem
alone. Using our methods the digital circuits are damped by shunting the
noise into the player's
ground plane and out of harms way. The sonic gains and
stunning increase in focus and fluidness are immediately obvious.
April 2008 -
Optional RFI Treatment A$100
Based on work done by Vacuum State agent Jim Ellis
of Sonic Perfectionists in United States. Read the Level 6 review of the
Vacuum
State DVP-S9000ES Level 6 for a description this RFI Treatment. The
same effects described also apply to the JLTi CD Player. Good news is that
the added cost is reasonable, and also, this will furnish the player with
an IEC Power Socket and the captive cord will be
discarded. Please make your intention clear at the time of placing
order. An IEC cord will not be supplied with player. Many will want
to experiment with their own choices, but a plain industrial type still
works well.
The JLTi CD Player
should be compared to the best players available and not really in
consideration to its price. By all means compare it with any other players
up to 10 times or more.
Let your ear
be your final arbiter.
Happy listening.
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